feat: added server config

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

@@ -0,0 +1,82 @@
+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")
+    }
+}