feat: added database config

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

@@ -0,0 +1,77 @@
+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/exceptions/CCoinException.kt

@@ -0,0 +1,8 @@
+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

@@ -0,0 +1,10 @@
+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

@@ -0,0 +1,9 @@
+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

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