feat: added wallet service

server/.gitignore

@@ -1,3 +1,7 @@
+# Go files
+ccoin
+go.sum
+
 # Compiled class file
 *.class
 

server/Dockerfile

@@ -1,67 +0,0 @@
-# Multi-stage build for Java 24
-FROM openjdk:24-jdk-slim AS builder
-
-# Install required packages
-RUN apt-get update && apt-get install -y \
-    curl \
-    unzip \
-    && rm -rf /var/lib/apt/lists/*
-
-# Set working directory
-WORKDIR /app
-
-# Copy gradle wrapper and build files
-COPY gradle/ gradle/
-COPY gradlew .
-COPY gradle.properties .
-COPY settings.gradle.kts .
-COPY build.gradle.kts .
-
-# Make gradlew executable
-RUN chmod +x gradlew
-
-# Download dependencies (for better caching)
-RUN ./gradlew dependencies --no-daemon
-
-# Copy source code
-COPY src/ src/
-
-# Build the application
-RUN ./gradlew shadowJar --no-daemon
-
-# Runtime stage
-FROM openjdk:24-jdk-slim
-
-# Install required runtime packages
-RUN apt-get update && apt-get install -y \
-    curl \
-    && rm -rf /var/lib/apt/lists/*
-
-# Create app user
-RUN groupadd -r ccoin && useradd -r -g ccoin ccoin
-
-# Set working directory
-WORKDIR /app
-
-# Copy the built JAR from builder stage
-COPY --from=builder /app/build/libs/*.jar app.jar
-
-# Change ownership to app user
-RUN chown -R ccoin:ccoin /app
-
-# Switch to app user
-USER ccoin
-
-# Expose port
-EXPOSE 8080
-
-# Health check
-HEALTHCHECK --interval=30s --timeout=10s --start-period=60s --retries=3 \
-    CMD curl -f http://localhost:8080/health || exit 1
-
-# JVM options for production
-ENV JAVA_OPTS="-Xmx512m -Xms256m -XX:+UseG1GC -XX:+UseStringDeduplication"
-
-# Run the application
-CMD ["sh", "-c", "java $JAVA_OPTS -jar app.jar"]
-

server/Makefile

@@ -0,0 +1,49 @@
+# Go parameters
+GOCMD=go
+GOBUILD=$(GOCMD) build
+GOCLEAN=$(GOCMD) clean
+GOTEST=$(GOCMD) test
+GOGET=$(GOCMD) get
+GOMOD=$(GOCMD) mod
+GOFMT=gofmt
+GOLINT=golangci-lint
+
+# Binary names
+BINARY_NAME=ccoin
+BINARY_LINUX=$(BINARY_NAME)-linux-x64
+BINARY_MAC=$(BINARY_NAME)-macos-arm64
+BINARY_WINDOWS=$(BINARY_NAME)-windows-x64.exe
+
+# Build directory
+BUILD_DIR=build
+
+# Version info (can be overridden)
+VERSION?=1.0.0
+BUILD_TIME?=$(shell date -u '+%Y-%m-%d_%H:%M:%S')
+COMMIT?=$(shell git rev-parse HEAD)
+
+# Linker flags to embed version info
+LDFLAGS=-ldflags "-X ccoin/config/server.version=$(VERSION) -X ccoin/config/server.buildTime=$(BUILD_TIME) -X ccoin/config/server.commit=$(COMMIT) -s -w" -trimpath
+
+.PHONY: all build clean test coverage deps fmt lint vet help
+.PHONY: build-linux build-windows build-darwin run dev
+.PHONY: docker-build install uninstall
+
+# Default target
+all: clean deps fmt vet test build
+
+# Build the binary
+build:
+	$(GOBUILD) $(LDFLAGS) -o $(BUILD_DIR)/$(BINARY_NAME) -v
+
+# Build for Linux
+build-linux:
+	CGO_ENABLED=0 GOOS=linux GOARCH=amd64 $(GOBUILD) $(LDFLAGS) -o $(BUILD_DIR)/$(BINARY_LINUX) -v
+
+# Build for MacOS
+build-macos:
+	CGO_ENABLED=0 GOOS=darwin GOARCH=arm64 $(GOBUILD) $(LDFLAGS) -o $(BUILD_DIR)/$(BINARY_MAC) -v
+
+# Build for windows
+build-windows:
+	CGO_ENABLED=0 GOOS=windows GOARCH=amd64 $(GOBUILD) $(LDFLAGS) -o $(BUILD_DIR)/$(BINARY_WINDOWS) -v

server/build.gradle.kts

@@ -1,121 +0,0 @@
-val ktor_version: String by project
-val kotlin_version: String by project
-val logback_version: String by project
-val exposed_version: String by project
-val postgresql_version: String by project
-val hikari_version: String by project
-val flyway_version: String by project
-val bouncycastle_version: String by project
-
-plugins {
-    kotlin("jvm") version "2.2.21"
-    kotlin("plugin.serialization") version "2.2.21"
-    id("io.ktor.plugin") version "3.3.3"
-    id("com.gradleup.shadow") version "9.3.0"
-    id("org.flywaydb.flyway") version "11.19.0"
-    application
-}
-
-group = "org.ccoin"
-version = "1.0.0"
-
-application {
-    mainClass.set("org.ccoin.ServerKt")
-
-    val isDevelopment: Boolean = project.ext.has("development")
-    applicationDefaultJvmArgs = listOf("-Dio.ktor.development=$isDevelopment")
-}
-
-repositories {
-    mavenCentral()
-}
-
-dependencies {
-    // Ktor server
-    implementation("io.ktor:ktor-server-core-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-netty-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-content-negotiation-jvm:$ktor_version")
-    implementation("io.ktor:ktor-serialization-kotlinx-json-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-cors-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-call-logging-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-status-pages-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-compression-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-default-headers-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-host-common-jvm:$ktor_version")
-    implementation("io.ktor:ktor-server-config-yaml:$ktor_version")
-
-    // Database
-    implementation("org.jetbrains.exposed:exposed-core:$exposed_version")
-    implementation("org.jetbrains.exposed:exposed-dao:$exposed_version")
-    implementation("org.jetbrains.exposed:exposed-jdbc:$exposed_version")
-    implementation("org.jetbrains.exposed:exposed-java-time:$exposed_version")
-    implementation("org.postgresql:postgresql:$postgresql_version")
-    implementation("com.zaxxer:HikariCP:$hikari_version")
-    implementation("org.flywaydb:flyway-core:$flyway_version")
-    implementation("org.flywaydb:flyway-database-postgresql:$flyway_version")
-
-    // Logging
-    implementation("ch.qos.logback:logback-classic:$logback_version")
-    implementation("io.github.oshai:kotlin-logging-jvm:7.0.0")
-
-    // Crypto utilities
-    implementation("org.bouncycastle:bcprov-jdk18on:$bouncycastle_version")
-    implementation("org.bouncycastle:bcpkix-jdk18on:$bouncycastle_version")
-    
-    // JSON
-    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.7.3")
-    implementation("org.jetbrains.kotlinx:kotlinx-datetime:0.6.1")
-    
-    // Coroutines
-    implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:1.9.0")
-    
-    // Testing
-    testImplementation("io.ktor:ktor-server-test-host-jvm:$ktor_version")
-    testImplementation("org.jetbrains.kotlin:kotlin-test-junit:$kotlin_version")
-    testImplementation("io.mockk:mockk:1.13.13")
-    testImplementation("org.junit.jupiter:junit-jupiter:5.11.3")
-    testImplementation("org.testcontainers:testcontainers:1.20.3")
-    testImplementation("org.testcontainers:postgresql:1.20.3")
-    testImplementation("org.testcontainers:junit-jupiter:1.20.3")
-}
-
-tasks.withType<Test> {
-    useJUnitPlatform()
-}
-
-// Fat JAR configuration for Docker
-tasks.jar {
-    enabled = false
-}
-
-tasks.shadowJar {
-    archiveClassifier.set("")
-    manifest {
-        attributes["Main-Class"] = "org.ccoin.ServerKt"
-    }
-    mergeServiceFiles()
-}
-
-// Flyway configuration
-flyway {
-    url = "jdbc:postgresql://localhost:5432/ccoin"
-    user = "ccoin"
-    password = "ccoin"
-    locations = arrayOf("classpath:db/migration")
-    baselineOnMigrate = true
-    validateOnMigrate = true
-}
-
-// Docker build task
-tasks.register<Exec>("buildDocker") {
-    dependsOn("shadowJar")
-    commandLine("docker", "build", "-t", "ccoin-server:latest", ".")
-}
-
-// Development task
-tasks.register("dev") {
-    dependsOn("run")
-    doFirst {
-        project.ext.set("development", true)
-    }
-}

server/config/database/config.go

@@ -0,0 +1,207 @@
+package database
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"time"
+	"ccoin/utils"
+	"github.com/charmbracelet/log"
+	_ "github.com/jackc/pgx/v5/stdlib"
+	"os"
+)
+
+type DatabaseConfig struct {
+	DB *sql.DB
+	logger *log.Logger
+}
+
+// Holds database configuration
+type DatabaseSettings struct {
+	URL string
+	User string
+	Password string
+	MaxPoolSize int
+	MinIdle int
+	ConnTimeout time.Duration
+	IdleTimeout time.Duration
+	MaxLifetime time.Duration
+	ValidationQuery string
+}
+
+// Creates and initializes a new database configuration
+func NewDatabaseConfig() *DatabaseConfig {
+	return &DatabaseConfig{
+		logger: log.New(os.Stdout),
+	}
+}
+
+// Initializes the database connection
+func (dc *DatabaseConfig) Init() error {
+	dc.logger.Info("Initializing database connection...")
+
+	settings := dc.loadSettings()
+
+	// Create connection string
+	connStr := fmt.Sprintf("%s?user=%s&password=%s", settings.URL, settings.User, settings.Password)
+
+	// Open database connection
+	db, err := sql.Open("pgx", connStr)
+	if err != nil {
+		dc.logger.Error("Failed to open database connection", "error", err)
+		return fmt.Errorf("failed to open database: %w", err)
+	}
+
+	// Configure database connection pool
+	db.SetMaxOpenConns(settings.MaxPoolSize)
+	db.SetMaxIdleConns(settings.MinIdle)
+	db.SetConnMaxLifetime(settings.MaxLifetime)
+	db.SetConnMaxIdleTime(settings.IdleTimeout)
+
+	// Test the connection
+	ctx, cancel := context.WithTimeout(context.Background(), settings.ConnTimeout)
+	defer cancel()
+
+	if err := db.PingContext(ctx); err != nil {
+		dc.logger.Error("Failed to ping database", "error", err)
+		return fmt.Errorf("failed to ping database: %w", err)
+	}
+
+	dc.DB = db
+	dc.logger.Info("Database connection established successfully")
+
+	// Create tables if they don't exist
+	if err := dc.createTables(); err != nil {
+		return fmt.Errorf("failed to create tables: %w", err)
+	}
+
+	return nil
+}
+
+// Loads database settings from environment variables
+func (dc *DatabaseConfig) loadSettings() DatabaseSettings {
+	return DatabaseSettings{
+		URL: utils.GetEnvOrDefault("DATABASE_URL", "postgres://localhost:5432/ccoin"),
+		User: utils.GetEnvOrDefault("DATABASE_USER", "ccoin"),
+		Password: utils.GetEnvOrDefault("DATABASE_PASSWORD", "ccoin"),
+		MaxPoolSize: utils.GetEnvOrDefault("DATABASE_POOL_SIZE", 20),
+		ConnTimeout: 30 * time.Second,
+		IdleTimeout: 10 * time.Minute,
+		MaxLifetime: 30 * time.Minute,
+		ValidationQuery: "SELECT 1",
+	}
+}
+
+// Creates database tables if they don't exist
+func (dc *DatabaseConfig) createTables() error {
+	dc.logger.Info("Creating database tables if they don't exist...")
+
+	// Define tables
+	tables := []string{
+		// Wallets table
+		`CREATE TABLE IF NOT EXISTS wallets (
+			address VARCHAR(64) PRIMARY KEY,
+			balance DECIMAL(20,8) DEFAULT 0,
+			label VARCHAR(255),
+			password_hash VARCHAR(64),
+			created_at BIGINT NOT NULL,
+			last_activity BIGINT
+		)`,
+
+		// Transactions table
+		`CREATE TABLE IF NOT EXISTS transactions (
+			hash VARCHAR(64) PRIMARY KEY,
+			from_address VARCHAR(64),
+			to_address VARCHAR(64) NOT NULL,
+			amount DECIMAL(20,8) NOT NULL,
+			fee DECIMAL(20,8) DEFAULT 0,
+			memo TEXT,
+			block_hash VARCHAR(64),
+			timestamp BIGINT NOT NULL,
+			status VARCHAR(20) DEFAULT 'pending',
+			confirmations INTEGER DEFAULT 0
+		)`,
+
+		// Blocks table
+		`CREATE TABLE IF NOT EXISTS blocks (
+			hash VARCHAR(64) PRIMARY KEY,
+			previous_hash VARCHAR(64),
+			merkle_root VARCHAR(64) NOT NULL,
+			timestamp BIGINT NOT NULL,
+			difficulty INTEGER NOT NULL,
+			nonce BIGINT NOT NULL,
+			miner_address VARCHAR(64) NOT NULL,
+			reward DECIMAL(20,8) NOT NULL,
+			height SERIAL,
+			transaction_count INTEGER DEFAULT 0,
+			confirmations INTEGER DEFAULT 0
+		)`,
+	}
+
+	// Create tables
+	for _, tableSQL := range tables {
+		if _, err := dc.DB.Exec(tableSQL); err != nil {
+			dc.logger.Error("Failed to create table", "error", err, "sql", tableSQL)
+			return err
+		}
+	}
+
+	// Create indexes
+	indexes := []string{
+		// Wallets indexes
+		"CREATE INDEX IF NOT EXISTS idx_wallets_created_at ON wallets(created_at)",
+		"CREATE INDEX IF NOT EXISTS idx_wallets_last_activity ON wallets(last_activity)",
+
+		// Transactions indexes
+		"CREATE INDEX IF NOT EXISTS idx_transactions_from_address ON transactions(from_address)",
+		"CREATE INDEX IF NOT EXISTS idx_transactions_to_address ON transactions(to_address)",
+		"CREATE INDEX IF NOT EXISTS idx_transactions_block_hash ON transactions(block_hash)",
+		"CREATE INDEX IF NOT EXISTS idx_transactions_timestamp ON transactions(timestamp)",
+		"CREATE INDEX IF NOT EXISTS idx_transactions_status ON transactions(status)",
+
+		// Blocks indexes
+		"CREATE INDEX IF NOT EXISTS idx_blocks_height ON blocks(height)",
+		"CREATE INDEX IF NOT EXISTS idx_blocks_miner_address ON blocks(miner_address)",
+		"CREATE INDEX IF NOT EXISTS idx_blocks_timestamp ON blocks(timestamp)",
+		"CREATE INDEX IF NOT EXISTS idx_blocks_previous_hash ON blocks(previous_hash)",
+
+		// Foreign key-like indexes for referential integrity
+		"CREATE INDEX IF NOT EXISTS idx_transactions_from_wallet ON transactions(from_address)",
+		"CREATE INDEX IF NOT EXISTS idx_transactions_to_wallet ON transactions(to_address)",
+		"CREATE INDEX IF NOT EXISTS idx_blocks_miner_wallet ON blocks(miner_address)",
+	}
+
+	// Create indexes
+	for _, indexSQL := range indexes {
+		if _, err := dc.DB.Exec(indexSQL); err != nil {
+			dc.logger.Error("Failed to create index", "error", err, "sql", indexSQL)
+			return err
+		}
+	}
+
+	dc.logger.Info("Database tables and indexes created/verified successfully")
+	return nil
+}
+
+// Returns database connection information
+func (dc *DatabaseConfig) GetConnectionInfo() map[string]interface{} {
+	settings := dc.loadSettings()
+	return map[string]interface{}{
+		"url": settings.URL,
+		"user": settings.User,
+		"poolSize": settings.MaxPoolSize,
+	}
+}
+
+// Closes the database connection
+func (dc *DatabaseConfig) Close() error {
+	if dc.DB != nil {
+		return dc.DB.Close()
+	}
+	return nil
+}
+
+// Returns the database connection
+func (dc *DatabaseConfig) GetDB() *sql.DB {
+	return dc.DB
+}

server/config/server/config.go

@@ -0,0 +1,194 @@
+package server
+
+import (
+	"github.com/charmbracelet/log"
+	"fmt"
+	"os"
+	"time"
+	"ccoin/utils"
+)
+
+var version = "dev"
+var buildTime = time.Now().Format(time.RFC3339)
+var commit = "none"
+
+type ServerConfig struct {
+	// App details
+	Version string
+	BuildTime string
+	Commit string
+	BaseURL string
+	
+	// Server settings
+	Host string
+	Port int
+	DevelopmentMode bool
+
+	// Mining settings
+	MiningDifficulty int
+	MiningReward float64
+	BlockTimeTarget time.Duration
+
+	// Transaction settings
+	DefaultTransactionFee float64
+	MaxTransactionSize int
+	MaxMemoLength int
+
+	// Security settings
+	JWTSecret string
+	RateLimitRequests int
+	RateLimitWindow time.Duration
+
+	// Blockchain settings
+	MaxBlockSize int
+	MaxTransactionsPerBlock int
+	ConfirmationsRequired int
+
+	// API settings
+	MaxPageSize int
+	DefaultPageSize int
+	APITimeout time.Duration
+
+	// Logging settings
+	LogLevel string
+	logger *log.Logger
+}
+
+// Creates and initializes a new ServerConfig
+func NewServerConfig() *ServerConfig {
+	config := &ServerConfig{
+		logger: log.New(os.Stdout),
+	}
+
+	// Load configuration from environment variables with defaults
+	config.loadConfig()
+	config.logConfig()
+	config.validateConfig()
+
+	return config
+}
+
+// Loads configuration from environment variables with defaults
+func (c *ServerConfig) loadConfig() {
+	// App details (these would typically come from build-time variables)
+	c.Version = version
+	c.BuildTime = utils.GetEnvOrDefault("BUILD_TIME", buildTime)
+	c.BaseURL = utils.GetEnvOrDefault("BASE_URL", "http://localhost:8080")
+	c.Commit = commit
+
+	// Server settings
+	c.Host = utils.GetEnvOrDefault("SERVER_HOST", "0.0.0.0")
+	c.Port = utils.GetEnvOrDefault("SERVER_PORT", 8080)
+	c.DevelopmentMode = utils.GetEnvOrDefault("DEVELOPMENT_MODE", true)
+
+	// Mining settings
+	c.MiningDifficulty = utils.GetEnvOrDefault("MINING_DIFFICULTY", 4)
+	c.MiningReward = utils.GetEnvOrDefault("MINING_REWARD", 50.0)
+	c.BlockTimeTarget = time.Duration(utils.GetEnvOrDefault("BLOCK_TIME_TARGET", 600000)) * time.Millisecond // 10 minutes
+
+	// Transaction settings
+	c.DefaultTransactionFee = utils.GetEnvOrDefault("DEFAULT_TRANSACTION_FEE", 5.0)
+	c.MaxMemoLength = utils.GetEnvOrDefault("MAX_MEMO_LENGTH", 256)
+	c.MaxTransactionSize = utils.GetEnvOrDefault("MAX_TRANSACTION_SIZE", 1024*1024) // 1MB
+
+	// Security settings
+	c.JWTSecret = utils.GetEnvOrDefault("JWT_SECRET", "change-this-in-production")
+	c.RateLimitRequests = utils.GetEnvOrDefault("RATE_LIMIT_REQUESTS", 100)
+	c.RateLimitWindow = time.Duration(utils.GetEnvOrDefault("RATE_LIMIT_WINDOW", 60000)) * time.Millisecond // 1 minute
+
+	// Blockchain settings
+	c.MaxBlockSize = utils.GetEnvOrDefault("MAX_BLOCK_SIZE", 1024*1024) // 1MB
+	c.MaxTransactionsPerBlock = utils.GetEnvOrDefault("MAX_TRANSACTIONS_PER_BLOCK", 1000)
+	c.ConfirmationsRequired = utils.GetEnvOrDefault("CONFIRMATIONS_REQUIRED", 6)
+
+	// API Settings
+	c.MaxPageSize = utils.GetEnvOrDefault("MAX_PAGE_SIZE", 100)
+	c.DefaultPageSize = utils.GetEnvOrDefault("DEFAULT_PAGE_SIZE", 50)
+	c.APITimeout = time.Duration(utils.GetEnvOrDefault("API_TIMEOUT", 30000)) * time.Millisecond // 30 seconds
+
+	// Logging settings
+	c.LogLevel = utils.GetEnvOrDefault("LOG_LEVEL", "INFO")
+}
+
+// Logs the current configuration
+func (c *ServerConfig) logConfig() {
+	c.logger.Info("Server configuration loaded:")
+	c.logger.Info("Host", "value", c.Host)
+	c.logger.Info("Port", "value", c.Port)	
+	c.logger.Info("Version", "value", c.Version)
+	c.logger.Info("Development mode", "value", c.DevelopmentMode)
+	c.logger.Info("Mining difficulty", "value", c.MiningDifficulty)
+	c.logger.Info("Mining reward", "value", c.MiningReward)
+	c.logger.Info("Block time target", "value", c.BlockTimeTarget)
+	c.logger.Info("Default transaction fee", "value", c.DefaultTransactionFee)
+	c.logger.Info("Confirmations required", "value", c.ConfirmationsRequired)
+	c.logger.Info("Max block size", "value", c.MaxBlockSize)
+	c.logger.Info("Max transactions per block", "value", c.MaxTransactionsPerBlock)
+	c.logger.Info("Max transaction size", "value", c.MaxTransactionSize)
+	c.logger.Info("Log level", "value", c.LogLevel)
+	c.logger.Info("Max page size", "value", c.MaxPageSize)
+
+	if c.JWTSecret == "change-this-in-production" && !c.DevelopmentMode {
+		c.logger.Warn("Using default JWT secret in production mode!")
+	}
+}
+
+// Returns a map of server information
+func (c *ServerConfig) GetServerInfo() map[string]interface{} {
+	return map[string]interface{}{
+		"host": c.Host,
+		"port": c.Port,
+		"development_mode": c.DevelopmentMode,
+		"version": c.Version,
+		"mining_difficulty": c.MiningDifficulty,
+		"mining_reward": c.MiningReward,
+		"block_time_target": c.BlockTimeTarget,
+		"confirmations_required": c.ConfirmationsRequired,
+	}
+}
+
+// Validates the configuration values
+func (c *ServerConfig) ValidateConfig() error {
+	if c.Port < 1 || c.Port > 65535 {
+		return fmt.Errorf("port must be between 1 and 65535")
+	}
+
+	if c.MiningDifficulty < 1 || c.MiningDifficulty > 32 {
+		return fmt.Errorf("mining difficulty must be between 1 and 32")
+	}
+
+	if c.MiningReward <= 0 {
+		return fmt.Errorf("mining reward must be positive")
+	}
+
+	if c.BlockTimeTarget <= 0 {
+		return fmt.Errorf("block time target must be positive")
+	}
+
+	if c.DefaultTransactionFee < 0 {
+		return fmt.Errorf("default transaction fee cannot be negative")
+	}
+
+	if c.ConfirmationsRequired <= 0 {
+		return fmt.Errorf("confirmations required must be positive")
+	}
+
+	if c.MaxPageSize <= 0 {
+		return fmt.Errorf("max page size must be positive")
+	}
+
+	if c.DefaultPageSize <= 0 {
+		return fmt.Errorf("default page size must be positive")
+	}
+
+	c.logger.Info("Server configuration validation passed")
+	return nil
+}
+
+// Wrapper that panics on validation error (similar to Kotlin's require)
+func (c *ServerConfig) validateConfig() {
+	if err := c.ValidateConfig(); err != nil {
+		// panic(err)
+		c.logger.Fatal("ERROR", "error", err)
+	}
+}

server/docker-compose.yml

@@ -1,82 +0,0 @@
-services:
-  # Postgres Database
-  postgres:
-    image: postgres:17-alpine
-    container_name: ccoin-postgres
-    restart: unless-stopped
-    environment:
-      POSTGRES_DB: ccoin
-      POSTGRES_USER: ccoin
-      POSTGRES_PASSWORD: ccoin
-      POSTGRES_INITDB_ARGS: "--encoding=UTF-8 --lc-collate=C --lc-ctype=C"
-    ports:
-      - "5432:5432"
-    volumes:
-      - postgres_data:/var/lib/postgresql/data
-      - ./docker/postgres/init:/docker-entrypoint-initdb.d
-    networks:
-      - ccoin-network
-    healthcheck:
-      test: ["CMD-SHELL", "pg_isready -U ccoin -d ccoin"]
-      interval: 10s
-      timeout: 5s
-      retries: 5
-      start_period: 30s
-
-  # CCoin server
-  ccoin-server:
-    build:
-      context: .
-      dockerfile: Dockerfile
-    container_name: ccoin-server
-    restart: unless-stopped
-    ports:
-      - "8080:8080"
-    depends_on:
-      postgres:
-        condition: service_healthy
-    environment:
-      # Database configuration
-      DATABASE_URL: jdbc:postgresql://postgres:5432/ccoin
-      DATABASE_USER: ccoin
-      DATABASE_PASSWORD: ccoin
-      DATABASE_POOL_SIZE: 20
-
-      # Server configuration
-      SERVER_HOST: 0.0.0.0
-      SERVER_PORT: 8080
-      
-      # Mining configuration
-      MINING_DIFFICULTY: 4
-      MINING_REWARD: 50.0
-      BLOCK_TIME_TARGET: 600000
-
-      # Security
-      JWT_SECRET: your-super-secret-jwt-key-change-this-in-production
-
-      # Logging
-      LOG_LEVEL: INFO
-
-      # Development
-      DEVELOPMENT_MODE: false
-    volumes:
-      - ./logs:/app/logs
-    networks:
-      - ccoin-network
-    healthcheck:
-      test: ["CMD", "curl", "-f", "http://localhost:8080/health"]
-      interval: 30s
-      timeout: 10s
-      retries: 3
-      start_period: 60s
-
-volumes:
-  postgres_data:
-    driver: local
-
-networks:
-  ccoin-network:
-    driver: bridge
-    ipam:
-      config:
-        - subnet: 172.20.0.0/16

server/go.mod

@@ -0,0 +1,33 @@
+module ccoin
+
+go 1.25.5
+
+require (
+	github.com/charmbracelet/log v0.4.2
+	github.com/gorilla/mux v1.8.1
+	github.com/jackc/pgx/v5 v5.7.6
+)
+
+require (
+	github.com/aymanbagabas/go-osc52/v2 v2.0.1 // indirect
+	github.com/charmbracelet/colorprofile v0.2.3-0.20250311203215-f60798e515dc // indirect
+	github.com/charmbracelet/lipgloss v1.1.0 // indirect
+	github.com/charmbracelet/x/ansi v0.8.0 // indirect
+	github.com/charmbracelet/x/cellbuf v0.0.13-0.20250311204145-2c3ea96c31dd // indirect
+	github.com/charmbracelet/x/term v0.2.1 // indirect
+	github.com/go-logfmt/logfmt v0.6.0 // indirect
+	github.com/jackc/pgpassfile v1.0.0 // indirect
+	github.com/jackc/pgservicefile v0.0.0-20240606120523-5a60cdf6a761 // indirect
+	github.com/jackc/puddle/v2 v2.2.2 // indirect
+	github.com/lucasb-eyer/go-colorful v1.2.0 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mattn/go-runewidth v0.0.16 // indirect
+	github.com/muesli/termenv v0.16.0 // indirect
+	github.com/rivo/uniseg v0.4.7 // indirect
+	github.com/xo/terminfo v0.0.0-20220910002029-abceb7e1c41e // indirect
+	golang.org/x/crypto v0.37.0 // indirect
+	golang.org/x/exp v0.0.0-20231006140011-7918f672742d // indirect
+	golang.org/x/sync v0.13.0 // indirect
+	golang.org/x/sys v0.32.0 // indirect
+	golang.org/x/text v0.24.0 // indirect
+)

server/gradle.properties

@@ -1,24 +0,0 @@
-# Ktor
-ktor_version=3.3.3
-kotlin_version=2.2.21
-
-# Database
-exposed_version=0.56.0
-postgresql_version=42.7.4
-hikari_version=6.0.0
-flyway_version=11.19.0
-
-# Crypto
-bouncycastle_version=1.78.1
-
-# Logging
-logback_version=1.5.12
-
-# Gradle
-kotlin.code.style=official
-org.gradle.jvmargs=-Xmx2048m -Dfile.encoding=UTF-8
-org.gradle.caching=true
-org.gradle.parallel=true
-
-# Application
-ccoin.version=1.0.0

server/models/api/model.go

@@ -0,0 +1,70 @@
+package api
+
+type ApiResponse[T any] struct {
+	Success bool `json:"success"`
+	Data *T `json:"data,omitempty"` // Nullable data
+	Error *string `json:"error,omitempty"` // Nullable error message
+	Timestamp int64 `json:"timestamp"`
+}
+
+type ErrorResponse struct {
+	Error string `json:"error"`
+	Code *string `json:"code,omitempty"`
+	Details map[string]string `json:"details,omitempty"`
+	Timestamp int64 `json:"timestamp"`
+}
+
+type SuccessResponse struct {
+	Message string `json:"message"`
+	Timestamp int64 `json:"timestamp"`
+}
+
+type HealthResponse struct {
+	Status string `json:"status"`
+	Version string `json:"version"`
+	Uptime int64 `json:"uptime"`
+	Database DatabaseHealth `json:"database"`
+	BlockChain BlockChainHealth `json:"blockchain"`
+}
+
+type DatabaseHealth struct {
+	Connected bool `json:"connected"`
+	ResponseTime int64 `json:"response_time"`
+	ActiveConnections int `json:"active_connections"`
+	MaxConnections int `json:"max_connections"`
+}
+
+type BlockChainHealth struct {
+	LatestBlock int `json:"latest_block"`
+	PendingTransactions int `json:"pending_transactions"`
+	NetworkHashRate float64 `json:"network_hash_rate"`
+	AverageBlockTime int64 `json:"average_block_time"`
+}
+
+type PaginationRequest struct {
+	Page int `json:"page"`
+	PageSize int `json:"page_size"`
+	SortBy *string `json:"sort_by,omitempty"`
+	SortOrder SortOrder `json:"sort_order"`
+}
+
+type PaginatedResponse[T any] struct {
+	Data []T `json:"data"`
+	Pagination PaginationInfo `json:"pagination"`
+}
+
+type PaginationInfo struct {
+	CurrentPage int `json:"current_page"`
+	PageSize int `json:"page_size"`
+	TotalItems int `json:"total_items"`
+	TotalPages int `json:"total_pages"`
+	HasNext bool `json:"has_next"`
+	HasPrevious bool `json:"has_previous"`
+}
+
+type SortOrder string
+
+const (
+	ASC SortOrder = "ASC"
+	DESC SortOrder = "DESC"
+)

server/models/block/model.go

@@ -0,0 +1,46 @@
+package block
+
+type StartMiningRequest struct {
+	MinerAddress string `json:"miner_address"`
+	Difficulty int `json:"difficulty"`
+}
+
+type SubmitMiningRequest struct {
+	MinerAddress string `json:"miner_address"`
+	Hash string `json:"hash"`
+	Nonce int64 `json:"nonce"`
+	PreviousHash *string `json:"previous_hash,omitempty"`
+	Timestamp int64 `json:"timestamp"`
+}
+
+type BlockResponse struct {
+	Hash string `json:"hash"`
+	PreviousHash *string `json:"previous_hash,omitempty"`
+	MerkleRoot string `json:"merkle_root"`
+	Timestamp int64 `json:"timestamp"`
+	Difficulty int `json:"difficulty"`
+	Nonce int64 `json:"nonce"`
+	MinerAddress string `json:"miner_address"`
+	Reward float64 `json:"reward"`
+	Height int `json:"height"`
+	TransactionCount int `json:"transaction_count"`
+	Confirmations int `json:"confirmations"`
+}
+
+type MiningStatsResponse struct {
+	MinerAddress string `json:"miner_address"`
+	TotalBlocksMined int `json:"total_blocks_mined"`
+	TotalRewardsEarned float64 `json:"total_rewards_earned"`
+	LastBlockMined *int64 `json:"last_block_mined,omitempty"`
+	CurrentDifficulty int `json:"current_difficulty"`
+}
+
+type MiningJobResponse struct {
+	JobId string `json:"job_id"`
+	Target string `json:"target"`
+	Difficulty int `json:"difficulty"`
+	PreviousHash string `json:"previous_hash"`
+	Height int `json:"height"`
+	Timestamp int64 `json:"timestamp"`
+	ExpiresAt int64 `json:"expires_at"`
+}

server/models/transaction/model.go

@@ -0,0 +1,39 @@
+package transaction
+
+type SendTransactionRequest struct {
+	FromAddress string `json:"from_address"`
+	ToAddress string `json:"to_address"`
+	Amount float64 `json:"amount"`
+	Fee float64 `json:"fee"`
+	Memo *string `json:"memo,omitempty"`
+	Password string `json:"password"`
+}
+
+type TransactionResponse struct {
+	Hash string `json:"hash"`
+	FromAddress *string `json:"from_address,omitempty"`
+	ToAddress string `json:"to_address"`
+	Amount float64 `json:"amount"`
+	Fee float64 `json:"fee"`
+	Memo *string `json:"memo,omitempty"`
+	BlockHash string `json:"block_hash"`
+	Timestamp int64 `json:"timestamp"`
+	Status string `json:"status"`
+	Confirmations int `json:"confirmations"`
+}
+
+type TransactionHistoryResponse struct {
+	Transactions []TransactionResponse `json:"transactions"`
+	TotalCount int `json:"total_count"`
+	Page int `json:"page"`
+	PageSize int `json:"page_size"`
+}
+
+type TransactionStatus string
+
+const (
+	PENDING TransactionStatus = "PENDING"
+	CONFIRMED TransactionStatus = "CONFIRMED"
+	FAILED TransactionStatus = "FAILED"
+	CANCELLED TransactionStatus = "CANCELLED"
+)

server/models/wallet/model.go

@@ -0,0 +1,35 @@
+package wallet
+
+import "time"
+
+type Wallet struct {
+	Address string `db:"address" json:"address"`
+	Label *string `db:"label" json:"label,omitempty"`
+	PasswordHash string `db:"password_hash" json:"password_hash"`
+	Balance float64 `db:"balance" json:"balance"`
+	CreatedAt time.Time `db:"created_at" json:"created_at"`
+	LastActivity *time.Time `db:"last_activity" json:"last_activity,omitempty"`
+}
+
+type CreateWalletRequest struct {
+	Label *string `json:"label,omitempty"`
+	Password string `json:"password"`
+}
+
+type WalletResponse struct {
+	Address string `json:"address"` // Format: "random_word:123456" (e.g. "cave:595462")
+	Balance float64 `json:"balance"`
+	Label *string `json:"label,omitempty"`
+	PasswordHash string `json:"password_hash"`
+	CreatedAt int64 `json:"created_at"`
+	LastActivity *int64 `json:"last_activity,omitempty"`
+}
+
+type BalanceResponse struct {
+	Address string `json:"address"`
+	Balance float64 `json:"balance"`
+}
+
+type UpdateWalletRequest struct {
+	Label *string `json:"label,omitempty"`
+}

server/routes/wallet/routes.go

@@ -0,0 +1,35 @@
+package routes
+
+import (
+	"ccoin/models/wallet"
+	ws "ccoin/services/wallet"
+	"encoding/json"
+	"net/http"
+	"github.com/gorilla/mux"
+)
+
+// Sets up routes for wallet operations
+func WalletRoutes(router *mux.Router, walletService *ws.WalletService) {
+	walletRouter := router.PathPrefix("/wallet").Subrouter()
+
+	// Create a new wallet
+	walletRouter.HandleFunc("/create", func(w http.ResponseWriter, r *http.Request) {
+		var req wallet.CreateWalletRequest
+
+		// Parse the request
+		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
+			http.Error(w, "Invalid request format", http.StatusBadRequest)
+			return
+		}
+
+		// Create the wallet using the service
+		walletResponse, err := walletService.CreateWallet(req)
+		if err != nil {
+			http.Error(w, "Failed to create wallet: "+err.Error(), http.StatusInternalServerError)
+			return
+		}
+
+		w.WriteHeader(http.StatusCreated)
+		json.NewEncoder(w).Encode(walletResponse)
+	}).Methods("POST")
+}

server/server.go

@@ -0,0 +1,35 @@
+package main
+
+import (
+    "ccoin/config/database"
+	"ccoin/config/server"
+    "ccoin/routes/wallet"
+	ws "ccoin/services/wallet"
+    "github.com/gorilla/mux"
+    "net/http"
+    "github.com/charmbracelet/log"
+)
+
+func main() {
+	// Initialize server
+	server.NewServerConfig()
+
+    // Initialize database
+    dbConfig := database.NewDatabaseConfig()
+    if err := dbConfig.Init(); err != nil {
+        log.Fatal("Database initialization failed:", err)
+    }
+
+    walletService := ws.NewWalletService(dbConfig.GetDB())
+
+    // Set up router
+    r := mux.NewRouter()
+    routes.WalletRoutes(r, walletService)
+
+    // Start server
+    log.Info("Starting server on :8080")
+    if err := http.ListenAndServe(":8080", r); err != nil {
+        log.Fatal("Failed to start server:", err)
+    }
+}
+

server/services/wallet/service.go

@@ -0,0 +1,219 @@
+package wallet
+
+import (
+	"ccoin/utils/crypto"
+	"database/sql"
+	"ccoin/models/wallet"
+	"errors"
+	"fmt"
+	"time"
+)
+
+type WalletService struct {
+	db *sql.DB
+}
+
+// Creates a new instance of WalletService
+func NewWalletService(db *sql.DB) *WalletService {
+	return &WalletService{db: db}
+}
+
+// Creates a new wallet with optional label
+func (ws *WalletService) CreateWallet(req wallet.CreateWalletRequest) (wallet.WalletResponse, error) {
+	address := crypto.GenerateWalletAddress()
+	timestamp := time.Now()
+	var passwordHash string
+	if req.Password != "" {
+		passwordHash = crypto.HashPassword(req.Password)
+	} else {
+		return wallet.WalletResponse{}, fmt.Errorf("password field is required")
+	}
+
+	_, err := ws.db.Exec(`
+		INSERT INTO wallets (address, balance, label, password_hash, created_at) 
+        VALUES ($1, $2, $3, $4, $5)`,
+		address, 0.0, req.Label, passwordHash, timestamp.Unix(),
+	)
+	if err != nil {
+		return wallet.WalletResponse{}, err
+	}
+
+	return wallet.WalletResponse{
+		Address: address,
+		Balance: 0.0,
+		Label: req.Label,
+		PasswordHash: passwordHash,
+		CreatedAt: timestamp.Unix(),
+		LastActivity: nil,
+	}, nil
+}
+
+// Gets wallet by address
+func (ws *WalletService) GetWallet(address string) (*wallet.WalletResponse, error) {
+	var w wallet.Wallet
+	row := ws.db.QueryRow(`
+		SELECT address, balance, label, password_hash, created_at, last_activity
+		FROM wallets WHERE address = $1`, address)
+	
+	err := row.Scan(&w.Address, &w.Balance, &w.Label, &w.PasswordHash, &w.CreatedAt, &w.LastActivity)
+	if err != nil {
+		return nil, err
+	}
+
+	return &wallet.WalletResponse{
+		Address: w.Address,
+		Balance: w.Balance,
+		Label: w.Label,
+		PasswordHash: w.PasswordHash,
+		CreatedAt: w.CreatedAt.Unix(),
+		LastActivity: ptrTime(w.LastActivity),
+	}, nil
+}
+
+// Gets wallet balance
+func (ws *WalletService) GetWalletBalance(address string) (wallet.BalanceResponse, error) {
+	var balance float64
+	err := ws.db.QueryRow(`SELECT balance FROM wallets WHERE address = $1`, address).Scan(&balance)
+	if err != nil {
+		return wallet.BalanceResponse{}, errors.New("wallet not found")
+	}
+	return wallet.BalanceResponse{
+		Address: address,
+		Balance: balance,
+	}, nil
+}
+
+// Updates wallet balance
+func (ws *WalletService) UpdateBalance(address string, amount float64) (bool, error) {
+	_, err := ws.db.Exec(`UPDATE wallets SET balance = balance + $1, last_activity = $2 WHERE address = $3`, amount, time.Now().Unix(), address)
+	if err != nil {
+		return false, err
+	}
+	return true, nil
+}
+
+// Sets wallet balance to specific amount
+func (ws *WalletService) SetBalance(address string, amount float64) (bool, error) {
+	_, err := ws.db.Exec(`UPDATE wallets SET balance = $1, last_activity = $2 WHERE address = $3`, amount, time.Now().Unix(), address)
+	if err != nil {
+		return false, err
+	}
+	return true, nil
+}
+
+// Updates wallet label
+func (ws *WalletService) UpdateLabel(address string, req wallet.UpdateWalletRequest) (bool, error) {
+	result, err := ws.db.Exec(`UPDATE wallets SET label = $1 WHERE address = $2`, address, req.Label)
+	if err != nil {
+		return false, err
+	}
+	rowsAffected, _ := result.RowsAffected()
+	return rowsAffected > 0, nil
+}
+
+// Checks if wallet exists
+func (ws *WalletService) WalletExists(address string) (bool, error) {
+    var count int64
+    err := ws.db.QueryRow(`SELECT COUNT(*) FROM wallets WHERE address = $1`, address).Scan(&count)
+    if err != nil {
+        return false, err
+    }
+    return count > 0, nil
+}
+
+// Gets all wallets with pagination
+func (ws *WalletService) GetAllWallets(limit, offset int) ([]wallet.WalletResponse, error) {
+    query := fmt.Sprintf(`
+        SELECT address, balance, label, password_hash, created_at, last_activity 
+        FROM wallets ORDER BY created_at DESC LIMIT %d OFFSET %d`, limit, offset)
+
+    rows, err := ws.db.Query(query)
+    if err != nil {
+        return nil, err
+    }
+    defer rows.Close()
+
+    var wallets []wallet.WalletResponse
+    for rows.Next() {
+        var w wallet.Wallet
+        if err := rows.Scan(&w.Address, &w.Balance, &w.Label, &w.PasswordHash, 
+                           &w.CreatedAt, &w.LastActivity); err != nil {
+            return nil, err
+        }
+
+        wallets = append(wallets, wallet.WalletResponse{
+            Address:      w.Address,
+            Balance:      w.Balance,
+            Label:        w.Label,
+            PasswordHash: w.PasswordHash,
+            CreatedAt:    w.CreatedAt.Unix(),
+            LastActivity: ptrTime(w.LastActivity),
+        })
+    }
+    return wallets, nil
+}
+
+// Gets total number of wallets
+func (ws *WalletService) GetTotalWalletCount() (int64, error) {
+    var count int64
+    err := ws.db.QueryRow(`SELECT COUNT(*) FROM wallets`).Scan(&count)
+    if err != nil {
+        return 0, err
+    }
+    return count, nil
+}
+
+// Gets wallet with balance greater than specified amount
+func (ws *WalletService) GetWalletsWithBalance(minBalance float64) ([]wallet.WalletResponse, error) {
+	rows, err := ws.db.Query(`SELECT address, balance, label, password_hash, created_at, last_activity FROM wallets WHERE balance > $1 ORDER BY balance DESC`, minBalance)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var wallets []wallet.WalletResponse
+	for rows.Next() {
+		var w wallet.Wallet
+		if err := rows.Scan(&w.Address, &w.Balance, &w.Label, &w.PasswordHash, &w.CreatedAt, &w.LastActivity); err != nil {
+			return nil, err
+		}
+		
+		wallets = append(wallets, wallet.WalletResponse{
+			Address: w.Address,
+			Balance: w.Balance,
+			Label: w.Label,
+			PasswordHash: w.PasswordHash,
+			CreatedAt: w.CreatedAt.Unix(),
+			LastActivity: ptrTime(w.LastActivity),
+		})
+	}
+	return wallets, nil
+}
+
+// Updates last activity timestamp
+func (ws *WalletService) UpdateLastActivity(address string) (bool, error) {
+	_, err := ws.db.Exec(`UPDATE wallets SET last_activity = $1 WHERE address = $2`, time.Now().Unix(), address)
+	if err != nil {
+		return false, err
+	}
+	return true, nil
+}
+
+// Gets total supply across all wallets
+func (ws *WalletService) GetTotalSupply() (float64, error) {
+	var totalSupply float64
+	err := ws.db.QueryRow(`SELECT SUM(balance) FROM wallets`).Scan(&totalSupply)
+	if err != nil {
+		return 0, err
+	}
+	return totalSupply, nil
+}
+
+// Helper function to convert *time.Time to *int64 for JSON response
+func ptrTime(t *time.Time) *int64 {
+	if t == nil {
+		return nil
+	}
+	unixTime := t.Unix()
+	return &unixTime
+}

server/src/main/kotlin/org/ccoin/Server.kt

@@ -1,5 +0,0 @@
-package org.ccoin
-
-fun main() {
-    println("CCoin Server Started")
-}

server/src/main/kotlin/org/ccoin/config/DatabaseConfig.kt

@@ -1,77 +0,0 @@
-package org.ccoin.config
-
-import com.zaxxer.hikari.HikariConfig
-import com.zaxxer.hikari.HikariDataSource
-import org.ccoin.database.Tables
-import org.jetbrains.exposed.sql.Database
-import org.jetbrains.exposed.sql.SchemaUtils
-import org.jetbrains.exposed.sql.transactions.transaction
-import org.slf4j.LoggerFactory
-
-object DatabaseConfig {
-    private val logger = LoggerFactory.getLogger(DatabaseConfig::class.java)
-
-    fun init() {
-        logger.info("Initializing database connection...")
-
-        val config = HikariConfig().apply {
-            driverClassName = "org.postgresql.Driver"
-            jdbcUrl = System.getenv("DATABASE_URL") ?: "jbdc:postgresql://localhost:5432/ccoin"
-            username = System.getenv("DATABASE_USER") ?: "ccoin"
-            password = System.getenv("DATABASE_PASSWORD") ?: "ccoin"
-
-            // Connection pool settings
-            maximumPoolSize = (System.getenv("DATABASE_POOL_SIZE")?.toIntOrNull() ?: 20)
-            minimumIdle = 5
-            connectionTimeout = 30000
-            idleTimeout = 600000
-            maxLifetime = 1800000
-
-            // Performance settings
-            isAutoCommit = false
-            transactionIsolation = "TRANSACTION_REPEATABLE_READ"
-
-            // Connection validation
-            connectionTestQuery = "SELECT 1"
-            validationTimeout = 5000
-
-            // Pool name for monitoring
-            poolName = "CCoinPool"
-        }
-
-        try {
-            val dataSource = HikariDataSource(config)
-            Database.connect(dataSource)
-
-            logger.info("Database connection established successfully")
-
-            // Create tables if they don't exist
-            createTables()
-        } catch(e: Exception) {
-            logger.error("Failed to initialize database connection", e)
-            throw e
-        }
-    }
-
-    private fun createTables() {
-        logger.info("Creating database tables if they don't exist...")
-
-        transaction {
-            SchemaUtils.create(
-                Tables.Wallets,
-                Tables.Transactions,
-                Tables.Blocks
-            )
-        }
-
-        logger.info("Database tables created/verified successfully")
-    }
-
-    fun getConnectionInfo(): Map<String, Any> {
-        return mapOf(
-            "url" to (System.getenv("DATABASE_URL") ?: "jdbc:postgresql://localhost:5432/ccoin"),
-            "user" to (System.getenv("DATABASE_USER") ?: "ccoin_user"),
-            "poolSize" to (System.getenv("DATABASE_POOL_SIZE")?.toIntOrNull() ?: 20)
-        )
-    }
-}

server/src/main/kotlin/org/ccoin/config/ServerConfig.kt

@@ -1,82 +0,0 @@
-package org.ccoin.config
-
-import org.slf4j.LoggerFactory
-
-object ServerConfig {
-    private val logger = LoggerFactory.getLogger(ServerConfig::class.java)
-
-    // Server settings
-    val host: String = System.getenv("SERVER_HOST") ?: "0.0.0.0"
-    val port: Int = System.getenv("SERVER_PORT")?.toIntOrNull() ?: 8080
-    val developmentMode: Boolean = System.getenv("DEVELOPMENT_MODE")?.toBoolean() ?: false
-
-    // Mining settings
-    val miningDifficulty: Int = System.getenv("MINING_DIFFICULTY")?.toIntOrNull() ?: 4
-    val miningReward: Double = System.getenv("MINING_REWARD")?.toDoubleOrNull() ?: 50.0
-    val blockTimeTarget: Long = System.getenv("BLOCK_TIME_TARGET")?.toLongOrNull() ?: 600000L // 10 minutes
-
-    // Transaction settings
-    val defaultTransactionFee: Double = System.getenv("DEFAULT_TRANSACTION_FEE")?.toDoubleOrNull() ?: 0.01
-    val maxTransactionSize: Int = System.getenv("MAX_TRANSACTION_SIZE")?.toIntOrNull() ?: (1024 * 1024) // 1MB
-    val maxMemoLength: Int = System.getenv("MAX_MEMO_LENGTH")?.toIntOrNull() ?: 256
-
-    // Security settings
-    val jwtSecret: String = System.getenv("JWT_SECRET") ?: "change-this-in-production"
-    val rateLimitRequests: Int = System.getenv("RATE_LIMIT_REQUESTS")?.toIntOrNull() ?: 100
-    val rateLimitWindow: Long = System.getenv("RATE_LIMIT_WINDOW")?.toLongOrNull() ?: 60000L // 1 minute
-
-    // Blockchain settings
-    val maxBlockSize: Int = System.getenv("MAX_BLOCK_SIZE")?.toIntOrNull() ?: 1024 * 1024 // 1MB
-    val maxTransactionsPerBlock: Int = System.getenv("MAX_TRANSACTIONS_PER_BLOCK")?.toIntOrNull() ?: 1000
-    val confirmationsRequired: Int = System.getenv("CONFIRMATIONS_REQUIRED")?.toIntOrNull() ?: 6
-
-    // API Settings
-    val maxPageSize: Int = System.getenv("MAX_PAGE_SIZE")?.toIntOrNull() ?: 100
-    val defaultPageSize: Int = System.getenv("DEFAULT_PAGE_SIZE")?.toIntOrNull() ?: 50
-    val apiTimeout: Long = System.getenv("API_TIMEOUT")?.toLongOrNull() ?: 30000L // 30 seconds
-
-    // Logging settings
-    val logLevel: String = System.getenv("LOG_LEVEL") ?: "INFO"
-
-    init {
-        logger.info("Server configuration loaded:")
-        logger.info("Host: $host")
-        logger.info("Port: $port")
-        logger.info("Development mode: $developmentMode")
-        logger.info("Mining difficulty: $miningDifficulty")
-        logger.info("Mining reward: $miningReward")
-        logger.info("Block time target: ${blockTimeTarget}ms")
-        logger.info("Default transaction fee: $defaultTransactionFee")
-        logger.info("Confirmations required: $confirmationsRequired")
-        
-        if (jwtSecret == "change-this-in-production" && !developmentMode) {
-            logger.warn("WARNING: Using default JWT secret in production mode!")
-        }
-    }
-
-    fun getServerInfo(): Map<String, Any> {
-        return mapOf(
-            "host" to host,
-            "port" to port,
-            "developmentMode" to developmentMode,
-            "version" to "1.0.0",
-            "miningDifficulty" to miningDifficulty,
-            "miningReward" to miningReward,
-            "blockTimeTarget" to blockTimeTarget,
-            "confirmationsRequired" to confirmationsRequired
-        )
-    }
-
-    fun validateConfig() {
-        require(port in 1..65535) { "Port must be between 1 and 65535" }
-        require(miningDifficulty in 1..32) { "Mining difficulty must be between 1 and 32" }
-        require(miningReward > 0) { "Mining reward must be positive" }
-        require(blockTimeTarget > 0) { "Block time target must be positive" }
-        require(defaultTransactionFee >= 0) { "Default transaction fee cannot be negative" }
-        require(confirmationsRequired > 0) { "Confirmations required must be positive" }
-        require(maxPageSize > 0) { "Max page size must be positive" }
-        require(defaultPageSize > 0) { "Default page size must be positive" }
-        
-        logger.info("Server configuration validation passed")
-    }
-}

server/src/main/kotlin/org/ccoin/database/Tables.kt

@@ -1,69 +0,0 @@
-package org.ccoin.database
-
-import org.jetbrains.exposed.sql.Table
-import org.jetbrains.exposed.sql.javatime.timestamp
-import java.math.BigDecimal
-
-object Tables {
-    object Wallets : Table("wallets") {
-        val address = varchar("address", 64) // Format random_word:random_6_digits
-        val balance = decimal("balance", 20, 8).default(BigDecimal.ZERO)
-        val label = varchar("label", 255).nullable()
-        val createdAt = long("created_at")
-        val lastActivity = long("last_activity").nullable()
-
-        override val primaryKey = PrimaryKey(address)
-
-        init {
-            index(false, createdAt)
-            index(false, lastActivity)
-        }
-    }    
-
-    object Transactions : Table("transactions") {
-        val hash = varchar("hash", 64)
-        val fromAddress = varchar("from_address", 64).nullable()
-        val toAddress = varchar("to_address", 64)
-        val amount = decimal("amount", 20, 8)
-        val fee = decimal("fee", 20, 8).default(BigDecimal.ZERO)
-        val memo = text("memo").nullable()
-        val blockHash = varchar("block_hash", 64).nullable()
-        val timestamp = long("timestamp")
-        val status = varchar("status", 20).default("pending")
-        val confirmations = integer("confirmations").default(0)
-
-        override val primaryKey = PrimaryKey(hash)
-
-        init {
-            index(false, fromAddress)
-            index(false, toAddress)
-            index(false, blockHash)
-            index(false, timestamp)
-            index(false, status)
-        }
-    }
-
-    object Blocks : Table("blocks") {
-        val hash = varchar("hash", 64)
-        val previousHash = varchar("previous_hash", 64).nullable()
-        val merkleRoot = varchar("merkle_root", 64)
-        val timestamp = long("timestamp")
-        val difficulty = integer("difficulty")
-        val nonce = long("nonce")
-        val minerAddress = varchar("miner_address", 64)
-        val reward = decimal("reward", 20, 8)
-        val height = integer("height").autoIncrement()
-        val transactionCount = integer("transaction_count").default(0)
-        val confirmations = integer("confirmations").default(0)
-
-        override val primaryKey = PrimaryKey(hash)
-
-        init {
-            index(false, height)
-            index(false, minerAddress)
-            index(false, timestamp)
-            index(false, previousHash)
-        }
-    }
-}
-

server/src/main/kotlin/org/ccoin/exceptions/CCoinException.kt

@@ -1,8 +0,0 @@
-package org.ccoin.exceptions
-
-/** Base exception class for all CCoin-related exceptions */
-open class CCoinException(
-    message: String,
-    cause: Throwable? = null,
-    val errorCode: String? = null
-) : Exception(message, cause)

server/src/main/kotlin/org/ccoin/exceptions/InsufficientFundsException.kt

@@ -1,10 +0,0 @@
-package org.ccoin.exceptions
-
-class InsufficientFundsException(
-    val address: String,
-    val requestedAmount: Double,
-    val availableBalance: Double
-) : CCoinException(
-    message = "Insufficient funds in wallet $address. Requested: $requestedAmount, Available: $availableBalance",
-    errorCode = "INSUFFICIENT_FUNDS"
-)

server/src/main/kotlin/org/ccoin/exceptions/InvalidTransactionException.kt

@@ -1,9 +0,0 @@
-package org.ccoin.exceptions
-
-class InvalidTransactionException(
-    message: String,
-    val transactionHash: String? = null
-) : CCoinException(
-    message = message,
-    errorCode = "INVALID_TRANSACTION"
-)

server/src/main/kotlin/org/ccoin/exceptions/WalletNotFoundException.kt

@@ -1,8 +0,0 @@
-package org.ccoin.exceptions
-
-class WalletNotFoundException(
-    val address: String
-) : CCoinException(
-    message = "Wallet with address '$address' not found",
-    errorCode = "WALLET_NOT_FOUND"
-)

server/src/main/kotlin/org/ccoin/models/ApiResponse.kt

@@ -1,80 +0,0 @@
-package org.ccoin.models
-
-import kotlinx.serialization.Serializable
-
-@Serializable
-data class ApiResponse<T>(
-    val success: Boolean,
-    val data: T? = null,
-    val error: String? = null,
-    val timestamp: Long = System.currentTimeMillis()
-)
-
-@Serializable
-data class ErrorResponse(
-    val error: String,
-    val code: String? = null,
-    val details: Map<String, String>? = null,
-    val timestamp: Long = System.currentTimeMillis()
-)
-
-@Serializable
-data class SuccessResponse(
-    val message: String,
-    val timestamp: Long = System.currentTimeMillis()
-)
-
-@Serializable
-data class HealthResponse(
-    val status: String,
-    val version: String,
-    val uptime: Long,
-    val database: DatabaseHealth,
-    val blockchain: BlockchainHealth
-)
-
-@Serializable
-data class DatabaseHealth(
-    val connected: Boolean,
-    val responseTime: Long,
-    val activeConnections: Int,
-    val maxConnections: Int
-)
-
-@Serializable
-data class BlockchainHealth(
-    val latestBlock: Int,
-    val pendingTransactions: Int,
-    val networkHashRate: Double,
-    val averageBlockTime: Long
-)
-
-@Serializable
-data class PaginationRequest(
-    val page: Int = 1,
-    val pageSize: Int = 50,
-    val sortBy: String? = null,
-    val sortOrder: SortOrder = SortOrder.DESC
-)
-
-@Serializable
-data class PaginatedResponse<T>(
-    val data: List<T>,
-    val pagination: PaginationInfo
-)
-
-@Serializable
-data class PaginationInfo(
-    val currentPage: Int,
-    val pageSize: Int,
-    val totalItems: Int,
-    val totalPages: Int,
-    val hasNext: Boolean,
-    val hasPrevious: Boolean
-)
-
-@Serializable
-enum class SortOrder {
-    ASC,
-    DESC
-}

server/src/main/kotlin/org/ccoin/models/Block.kt

@@ -1,53 +0,0 @@
-package org.ccoin.models
-
-import kotlinx.serialization.Serializable
-
-@Serializable
-data class StartMiningRequest(
-    val minerAddress: String, // Format: random_word:random_6_digits
-    val difficulty: Int? = null
-)
-
-@Serializable
-data class SubmitMiningRequest(
-    val minerAddress: String,
-    val nonce: Long,
-    val hash: String,
-    val previousHash: String,
-    val timestamp: Long
-)
-
-@Serializable
-data class BlockResponse(
-    val hash: String,
-    val previousHash: String?,
-    val merkleRoot: String,
-    val timestamp: Long,
-    val difficulty: Int,
-    val nonce: Long,
-    val minerAddress: String
-    val reward: Double,
-    val height: Int,
-    val transactionCount: Int,
-    val confirmations: Int = 0
-)
-
-@Serializable
-data class MiningJobResponse(
-   val jobId: String,
-   val target: String,
-   val difficulty: Int,
-   val previousHash: String,
-   val height: Int,
-   val timestamp: Long,
-   val expiresAt: Long
-)
-
-@Serializable
-data class MiningStatsResponse(
-    val minerAddress: String,
-    val totalBlocksMined: Int,
-    val totalRewardEarned: Double,
-    val lastBlockMined: Long?,
-    val currentDifficulty: Int
-)

server/src/main/kotlin/org/ccoin/models/Transaction.kt

@@ -1,42 +0,0 @@
-package org.ccoin.models
-
-import kotlinx.serialization.Serializable
-
-@Serializable
-data class SendTransactionRequest(
-    val fromAddress: String, // Format random_word:random_6_digits
-    val toAddress: String, // Format random_word:random_6_digits
-    val amount: Double,
-    val fee: Double = 0.0,
-    val memo: String? = null
-)
-
-@Serializable
-data class TransactionResponse(
-    val hash: String,
-    val fromAddress: String?,
-    val toAddress: String,
-    val amount: Double,
-    val fee: Double,
-    val memo: String?,
-    val blockHash: String?,
-    val timestamp: Long,
-    val status: TransactionStatus,
-    val confirmations: Int = 0
-)
-
-@Serializable
-data class TransactionHistoryResponse(
-    val transactions: List<TransactionResponse>,
-    val totalCount: Int,
-    val page: Int,
-    val pageSize: Int
-)
-
-@Serializable
-enum class TransactionStatus {
-    PENDING,
-    CONFIRMED,
-    FAILED,
-    CANCELLED
-}

server/src/main/kotlin/org/ccoin/models/Wallet.kt

@@ -1,28 +0,0 @@
-package org.ccoin.models
-
-import kotlinx.serialization.Serializable
-
-@Serializable
-data class CreateWalletRequest(
-    val label: String? = null
-)
-
-@Serializable
-data class WalletResponse(
-    val address: String, // Format random_word:random_6_digits (e.g. "phoenix:123456")
-    val balance: Double,
-    val label: String?,
-    val createdAt: Long,
-    val lastActivity: Long?
-)
-
-@Serializable
-data class BalanceResponse(
-    val address: String,
-    val balance: Double
-)
-
-@Serializable
-data class UpdateWalletRequest(
-    val label: String?
-)

server/src/main/kotlin/org/ccoin/services/WalletService.kt

@@ -1,138 +0,0 @@
-package org.ccoin.services
-
-import org.ccoin.database.Tables
-import org.ccoin.exceptions.WalletNotFoundException
-import org.ccoin.models.WalletResponse
-import org.ccoin.utils.CryptoUtils
-import org.jetbrains.exposed.sql.*
-import org.jetbrains.exposed.sql.transactions.transaction
-import java.math.BigDecimal
-import java.time.Instant
-
-object WalletService {
-    
-    /** Creates a new wallet with optional label */
-    fun createWallet(label: String? = null): WalletResponse {
-        val address = CryptoUtils.generateWalletAddress()
-        val timestamp = Instant.now().epochSecond
-        
-        return transaction {
-            Tables.Wallets.insert {
-                it[Tables.Wallets.address] = address
-                it[Tables.Wallets.label] = label
-                it[createdAt] = timestamp
-            }
-            
-            WalletResponse(address, 0.0, label, timestamp, null)
-        }
-    }
-    
-    /** Gets wallet by address */
-    fun getWallet(address: String): WalletResponse? = transaction {
-        Tables.Wallets.selectAll().where { Tables.Wallets.address eq address }
-            .map {
-                WalletResponse(
-                    it[Tables.Wallets.address],
-                    it[Tables.Wallets.balance].toDouble(),
-                    it[Tables.Wallets.label],
-                    it[Tables.Wallets.createdAt],
-                    it[Tables.Wallets.lastActivity]
-                )
-            }.singleOrNull()
-    }
-    
-    /** Gets wallet balance */
-    fun getWalletBalance(address: String): Double = transaction {
-        Tables.Wallets.selectAll().where { Tables.Wallets.address eq address }
-            .map { it[Tables.Wallets.balance].toDouble() }
-            .singleOrNull() ?: throw WalletNotFoundException(address)
-    }
-    
-    /** Updates wallet balance */
-    fun updateBalance(address: String, amount: BigDecimal): Boolean = transaction {
-        val currentBalance = Tables.Wallets.selectAll()
-            .where { Tables.Wallets.address eq address }
-            .map { it[Tables.Wallets.balance] }
-            .singleOrNull() ?: return@transaction false
-
-        val updated = Tables.Wallets.update({ Tables.Wallets.address eq address }) {
-            it[balance] = currentBalance.add(amount)
-            it[lastActivity] = Instant.now().epochSecond
-        }
-        updated > 0
-    }
-    
-    /** Sets wallet balance to specific amount */
-    fun setBalance(address: String, amount: BigDecimal): Boolean = transaction {
-        val updated = Tables.Wallets.update({ Tables.Wallets.address eq address }) {
-            it[balance] = amount
-            it[lastActivity] = Instant.now().epochSecond
-        }
-        updated > 0
-    }
-    
-    /** Updates wallet label */
-    fun updateLabel(address: String, label: String?): Boolean = transaction {
-        val updated = Tables.Wallets.update({ Tables.Wallets.address eq address }) {
-            it[Tables.Wallets.label] = label
-        }
-        updated > 0
-    }
-    
-    /** Checks if wallet exists */
-    fun walletExists(address: String): Boolean = transaction {
-        Tables.Wallets.selectAll().where { Tables.Wallets.address eq address }.count() > 0
-    }
-    
-    /** Gets all wallets with pagination */
-    fun getAllWallets(limit: Int = 50, offset: Int = 0): List<WalletResponse> = transaction {
-        Tables.Wallets.selectAll()
-            .orderBy(Tables.Wallets.createdAt, SortOrder.DESC)
-            .limit(limit)
-            .offset(offset.toLong())
-            .map {
-                WalletResponse(
-                    it[Tables.Wallets.address],
-                    it[Tables.Wallets.balance].toDouble(),
-                    it[Tables.Wallets.label],
-                    it[Tables.Wallets.createdAt],
-                    it[Tables.Wallets.lastActivity]
-                )
-            }
-    }
-    
-    /** Gets total number of wallets */
-    fun getTotalWalletCount(): Long = transaction {
-        Tables.Wallets.selectAll().count()
-    }
-    
-    /** Gets wallets with balance greater than specified amount */
-    fun getWalletsWithBalance(minBalance: Double): List<WalletResponse> = transaction {
-        Tables.Wallets.selectAll().where { Tables.Wallets.balance greater BigDecimal.valueOf(minBalance) }
-            .orderBy(Tables.Wallets.balance, SortOrder.DESC)
-            .map {
-                WalletResponse(
-                    it[Tables.Wallets.address],
-                    it[Tables.Wallets.balance].toDouble(),
-                    it[Tables.Wallets.label],
-                    it[Tables.Wallets.createdAt],
-                    it[Tables.Wallets.lastActivity]
-                )
-            }
-    }
-    
-    /** Updates last activity timestamp */
-    fun updateLastActivity(address: String): Boolean = transaction {
-        val updated = Tables.Wallets.update({ Tables.Wallets.address eq address }) {
-            it[lastActivity] = Instant.now().epochSecond
-        }
-        updated > 0
-    }
-    
-    /** Gets total supply across all wallets */
-    fun getTotalSupply(): Double = transaction {
-        Tables.Wallets.select(Tables.Wallets.balance.sum())
-            .single()[Tables.Wallets.balance.sum()]?.toDouble() ?: 0.0
-    }
-}
-

server/src/main/kotlin/org/ccoin/utils/CryptoUtils.kt

@@ -1,123 +0,0 @@
-package org.ccoin.utils
-
-import java.security.MessageDigest
-import java.security.SecureRandom
-import kotlin.random.Random
-
-object CryptoUtils {
-    private val secureRandom = SecureRandom()
-
-    // Word list for address generation
-    private val words = listOf(
-        "phoenix", "dragon", "tiger", "eagle", "wolf", "lion", "bear", "shark",
-        "falcon", "raven", "cobra", "viper", "panther", "jaguar", "leopard", "cheetah",
-        "thunder", "lightning", "storm", "blizzard", "tornado", "hurricane", "cyclone", "tempest",
-        "crystal", "diamond", "emerald", "ruby", "sapphire", "topaz", "amethyst", "opal",
-        "shadow", "ghost", "phantom", "spirit", "wraith", "specter", "demon", "angel",
-        "fire", "ice", "earth", "wind", "water", "metal", "wood", "void",
-        "star", "moon", "sun", "comet", "meteor", "galaxy", "nebula", "cosmos",
-        "blade", "sword", "arrow", "spear", "shield", "armor", "crown", "throne",
-        "mountain", "ocean", "forest", "desert", "valley", "river", "lake", "cave",
-        "knight", "warrior", "mage", "archer", "rogue", "paladin", "wizard", "sage"
-    )
-
-    /**
-     * Generates a wallet address in format: random_word:random_6_digits
-     * Example: "phoenix:123456", "dragon:654321"
-     */
-    fun generateWalletAddress(): String {
-        val randomWord = words[secureRandom.nextInt(words.size)]
-        val randomDigits = String.format("%06d", secureRandom.nextInt(1000000))
-        return "$randomWord:$randomDigits"
-    }
-
-    /** Validates if an address follows the correct format */
-    fun isValidAddress(address: String): Boolean {
-        val parts = address.split(":")
-        if (parts.size != 2) return false
-        
-        val word = parts[0]
-        val digits = parts[1]
-
-        return word.isNotEmpty() &&
-            word.all { it.isLetter() } &&
-            digits.length == 6 &&
-            digits.all { it.isDigit() }
-    }
-
-    /** Generates SHA-256 hash of input string */
-    fun sha256(input: String): String {
-        return MessageDigest.getInstance("SHA-256")
-            .digest(input.toByteArray())
-            .joinToString("") { "%02x".format(it) }
-    }
-
-    /** Generates a transaction hash */
-    fun generateTransactionHash(
-        fromAddress: String?,
-        toAddress: String,
-        amount: Double,
-        timestamp: Long,
-        nonce: Long = secureRandom.nextLong()
-    ): String {
-        val input = "${fromAddress ?: "genesis"}:$toAddress:$amount:$timestamp:$nonce"
-        return sha256(input)
-    }
-
-    /** Generates a block hash */
-    fun generateBlockHash(
-        previousHash: String,
-        merkleRoot: String,
-        timestamp: Long,
-        difficulty: Int,
-        nonce: Long
-    ): String {
-        val input = "$previousHash:$merkleRoot:$timestamp:$difficulty:$nonce"
-        return sha256(input)
-    }
-
-    /** Validates if a hash meets the mining difficulty requirement */
-    fun isValidHash(hash: String, difficulty: Int): Boolean {
-        val target = "0".repeat(difficulty)
-        return hash.startsWith(target)
-    }
-
-    /** Generates a mining job id */
-    fun generateJobId(): String = sha256("job:${System.currentTimeMillis()}:${secureRandom.nextLong()}").take(16)
-
-    /** Calculates a merkle root from transaction hashes */
-    fun calculateMerkleRoot(transactionHashes: List<String>): String {
-        if (transactionHashes.isEmpty()) {
-            return sha256("empty")
-        }
-        
-        if (transactionHashes.size == 1) {
-            return transactionHashes[0]
-        }
-        
-        var hashes = transactionHashes.toMutableList()
-        
-        while (hashes.size > 1) {
-            val newHashes = mutableListOf<String>()
-            
-            for (i in hashes.indices step 2) {
-                val left = hashes[i]
-                val right = if (i + 1 < hashes.size) hashes[i + 1] else left
-                newHashes.add(sha256("$left:$right"))
-            }
-            
-            hashes = newHashes
-        }
-        
-        return hashes[0]
-    }
-
-    /** Generates a random nonce for mining */
-    fun generateNonce(): Long = secureRandom.nextLong()
-
-    /** Validates transaction hash format */
-    fun isValidTransactionHash(hash: String): Boolean = hash.length == 64 && hash.all { it.isDigit() || it.lowercaseChar() in 'a'..'f' }
-
-    /** Validates block has format */
-    fun isValidBlockHash(hash: String): Boolean = hash.length == 64 && hash.all { it.isDigit() || it.lowercaseChar() in 'a'..'f' }
-}

server/src/main/kotlin/org/ccoin/utils/HashUtils.kt

@@ -1,80 +0,0 @@
-package org.ccoin.utils
-
-import java.security.MessageDigest
-import java.security.SecureRandom
-
-object HashUtils {
-    private val secureRandom = SecureRandom()
-    
-    /** Computes SHA-256 hash of a byte array */
-    fun sha256(data: ByteArray): ByteArray = MessageDigest.getInstance("SHA-256").digest(data)
-    
-    /** Computes SHA-256 hash of a string and returns hex string */
-    fun sha256Hex(input: String): String = sha256(input.toByteArray()).toHexString()
-    
-    /** Computes double SHA-256 hash (like Bitcoin) */
-    fun doubleSha256(data: ByteArray): ByteArray = sha256(sha256(data))
-    
-    /** Computes double SHA-256 hash and returns hex string */
-    fun doubleSha256Hex(input: String): String = doubleSha256(input.toByteArray()).toHexString()
-    
-    /** Converts byte array to hex string */
-    fun ByteArray.toHexString(): String = joinToString("") { "%02x".format(it) }
-    
-    /** Converts hex string to byte array */
-    fun String.hexToByteArray(): ByteArray {
-        require(length % 2 == 0) { "Hex string must have even length" }
-        return chunked(2).map { it.toInt(16).toByte() }.toByteArray()
-    }
-    
-    /** Validates if string is valid hex */
-    fun isValidHex(hex: String): Boolean = hex.all { it.isDigit() || it.lowercaseChar() in 'a'..'f' }
-    
-    /** Generates a random hash for testing purposes */
-    fun generateRandomHash(): String {
-        val randomBytes = ByteArray(32)
-        secureRandom.nextBytes(randomBytes)
-        return randomBytes.toHexString()
-    }
-    
-    /** Computes hash with salt for additional security */
-    fun hashWithSalt(input: String, salt: String): String = sha256Hex("$input:$salt")
-    
-    /** Generates a random salt */
-    fun generateSalt(length: Int = 16): String {
-        val saltBytes = ByteArray(length)
-        secureRandom.nextBytes(saltBytes)
-        return saltBytes.toHexString()
-    }
-    
-    /** Computes HMAC-SHA256 */
-    fun hmacSha256(key: String, message: String): String {
-        val keyBytes = key.toByteArray()
-        val messageBytes = message.toByteArray()
-        
-        val blockSize = 64
-        val adjustedKey = when {
-            keyBytes.size > blockSize -> sha256(keyBytes)
-            keyBytes.size < blockSize -> keyBytes + ByteArray(blockSize - keyBytes.size)
-            else -> keyBytes
-        }
-        
-        val outerPad = ByteArray(blockSize) { (adjustedKey[it].toInt() xor 0x5c).toByte() }
-        val innerPad = ByteArray(blockSize) { (adjustedKey[it].toInt() xor 0x36).toByte() }
-        
-        val innerHash = sha256(innerPad + messageBytes)
-        val finalHash = sha256(outerPad + innerHash)
-        
-        return finalHash.toHexString()
-    }
-    
-    /** Validates hash format (64 character hex string for SHA-256) */
-    fun isValidSha256Hash(hash: String): Boolean = hash.length == 64 && isValidHex(hash)
-    
-    /** Computes checksum for data integrity */
-    fun computeChecksum(data: String): String = sha256Hex(data).take(8)
-    
-    /** Validates data against checksum */
-    fun validateChecksum(data: String, checksum: String): Boolean = computeChecksum(data) == checksum
-}
-

server/utils/crypto/main.go

@@ -0,0 +1,131 @@
+package crypto
+
+import (
+	"crypto/sha256"
+	"fmt"
+	"ccoin/utils"
+	"strings"
+)
+
+var words = []string{
+    "phoenix", "dragon", "tiger", "eagle", "wolf", "lion", "bear", "shark",
+    "falcon", "raven", "cobra", "viper", "panther", "jaguar", "leopard", "cheetah",
+    "thunder", "lightning", "storm", "blizzard", "tornado", "hurricane", "cyclone", "tempest",
+    "crystal", "diamond", "emerald", "ruby", "sapphire", "topaz", "amethyst", "opal",
+    "shadow", "ghost", "phantom", "spirit", "wraith", "specter", "demon", "angel",
+    "fire", "ice", "earth", "wind", "water", "metal", "wood", "void",
+    "star", "moon", "sun", "comet", "meteor", "galaxy", "nebula", "cosmos",
+    "blade", "sword", "arrow", "spear", "shield", "armor", "crown", "throne",
+    "mountain", "ocean", "forest", "desert", "valley", "river", "lake", "cave",
+    "knight", "warrior", "mage", "archer", "rogue", "paladin", "wizard", "sage",
+}
+
+// Generates a wallet address in format: random_word:random_6_digits
+func GenerateWalletAddress() string {
+	randomWord := words[utils.RandInt(0, len(words))]
+	randomDigits := fmt.Sprintf("%06d", utils.RandInt(0, 1000000))
+	return fmt.Sprintf("%s:%s", randomWord, randomDigits)
+}
+
+// Validates if an address follows the correct format
+func IsValidAddress(address string) bool {
+	parts := strings.Split(address, ":")
+	if len(parts) != 2 {
+		return false
+	}
+
+	word := parts[0]
+	digits := parts[1]
+
+	return len(word) > 0 &&
+		utils.IsAlpha(word) &&
+		len(digits) == 6 &&
+		utils.IsDigit(digits)
+}
+
+// Generates SHA-256 hash of input string
+func SHA256(input string) string {
+	hash := sha256.New()
+	hash.Write([]byte(input))
+	return fmt.Sprintf("%x", hash.Sum(nil))
+}
+
+// Hashes password
+func HashPassword(password string) string {
+	return SHA256(fmt.Sprintf("ccoin_password_%s", password))
+}
+
+// Generates a transaction hash
+func GenerateTransactionHash(fromAddress *string, toAddress string, amount float64, timestamp int64, nonce int64) string {
+	from := "genesis"
+	if fromAddress != nil {
+		from = *fromAddress
+	}
+	input := fmt.Sprintf("%s:%s:%f:%d:%d", from, toAddress, amount, timestamp, nonce)
+	return SHA256(input)
+}
+
+// Generates a block hash
+func GenerateBlockHash(previousHash string, merkleRoot string, timestamp int64, difficulty int, nonce int64) string {
+	input := fmt.Sprintf("%s:%s:%d:%d:%d", previousHash, merkleRoot, timestamp, difficulty, nonce)
+	return SHA256(input)
+}
+
+// Validates if a hash meets the mining difficulty requirement
+func IsValidHash(hash string, difficulty int) bool {
+	target := strings.Repeat("0", difficulty)
+	return strings.HasPrefix(hash, target)
+}
+
+// Generates mining job id
+func GenerateJobId() string {
+	return SHA256(fmt.Sprintf("job:%d:%d", utils.GetCurrentTimeMillis(), utils.RandInt(0, 1<<63-1)))[:16]
+}
+
+// Calculate merkle root from transaction hashes
+func CalculateMerkleRoot(transactionHashes []string) string {
+	if len(transactionHashes) == 0 {
+		return SHA256("empty")
+	}
+
+	if len(transactionHashes) == 1 {
+		return transactionHashes[0]
+	}
+
+	hashes := transactionHashes	
+
+	for len(hashes) > 1 {
+		var newHashes []string
+		for i := 0; i < len(hashes); i += 2 {
+			left := hashes[i]
+			right := left // Default to left if there's no right
+			if i+1< len(hashes) {
+				right = hashes[i+1]
+			}
+			newHashes = append(newHashes, SHA256(fmt.Sprintf("%s:%s", left, right)))
+		}
+		hashes = newHashes
+	}
+
+	return hashes[0]
+}
+
+// Generates a random nonce for mining
+func GenerateNonce() int64 {
+	return int64(utils.RandInt(0, 1<<63-1))
+}
+
+// Validates transaction hash format
+func IsValidTransactionHash(hash string) bool {
+	return len(hash) == 64 && utils.IsHex(hash)
+}
+
+// Validates block hash format
+func IsValidBlockHash(hash string) bool {
+    return len(hash) == 64 && utils.IsHex(hash)
+}
+
+// Verifies password hash
+func VerifyPassword(password string, storedHash string) bool {
+    return HashPassword(password) == storedHash
+}

server/utils/env.go

@@ -0,0 +1,33 @@
+package utils
+
+import (
+	"os"
+	"strconv"
+)
+
+// Gets value from environment or uses default value
+func GetEnvOrDefault[T string | int | bool | float64](key string, defaultValue T) T {
+    value, exists := os.LookupEnv(key)
+    if !exists {
+        return defaultValue
+    }
+
+    // Handle conversion based on the type of defaultValue
+    switch any(defaultValue).(type) {
+    case string:
+        return any(value).(T)
+    case int:
+        if intValue, err := strconv.Atoi(value); err == nil {
+            return any(intValue).(T)
+        }
+    case bool:
+        if boolValue, err := strconv.ParseBool(value); err == nil {
+            return any(boolValue).(T)
+        }
+    case float64:
+        if floatValue, err := strconv.ParseFloat(value, 64); err == nil {
+            return any(floatValue).(T)
+        }
+    }
+    return defaultValue // return default value if conversion fails
+}

server/utils/extensions.go

@@ -0,0 +1,2 @@
+package utils
+

server/utils/general.go

@@ -0,0 +1,48 @@
+package utils
+
+import (
+	"crypto/rand"
+	"math/big"
+	"time"
+)
+
+// Generates a random integer in the range (min, max)
+func RandInt(min, max int) int {
+	n, _ := rand.Int(rand.Reader, big.NewInt(int64(max-min)))
+	return int(n.Int64()) + min
+}
+
+// Get the current time in milliseconds
+func GetCurrentTimeMillis() int64 {
+	return time.Now().UnixNano() / int64(time.Millisecond) // Convert nanoseconds to milliseconds
+}
+
+// IsAlpha checks if the string contains only alphabetic characters
+func IsAlpha(s string) bool {
+    for _, r := range s {
+        if !('a' <= r && r <= 'z') && !('A' <= r && r <= 'Z') {
+            return false
+        }
+    }
+    return true
+}
+
+// IsDigit checks if the string contains only digits
+func IsDigit(s string) bool {
+    for _, r := range s {
+        if !(r >= '0' && r <= '9') {
+            return false
+        }
+    }
+    return true
+}
+
+// IsHex checks if the string is a valid hexadecimal representation
+func IsHex(s string) bool {
+    for _, r := range s {
+        if !((r >= '0' && r <= '9') || (r >= 'a' && r <= 'f') || (r >= 'A' && r <= 'F')) {
+            return false
+        }
+    }
+    return true
+}

server/utils/hash/main.go

@@ -0,0 +1,2 @@
+package hash
+