/**
 * 配置处理模块
 * @module config
 */

import type { 
  PITBotAccountConfig, 
  ResolvedPITBotAccount 
} from "./types.js";
import type { OpenClawConfig } from "openclaw/plugin-sdk";
import { createLogger } from "./utils/logger.js";

const MODULE = "config";

interface PITChannelConfig extends PITBotAccountConfig {
  accounts?: Record<string, PITBotAccountConfig>;
}

/**
 * 默认账户 ID
 */
export const DEFAULT_ACCOUNT_ID = "default";

/**
 * 获取 PIT Bot 账户 ID 列表
 * @returns 账户 ID 列表
 */
export function listPITBotAccountIds(): string[] {
  return [DEFAULT_ACCOUNT_ID];
}

/**
 * 解析 PIT Bot 账户
 * @param cfg OpenClaw 配置
 * @param accountId 账户 ID
 * @returns 解析后的账户配置
 * @throws 如果配置无效
 */
export function resolvePITBotAccount(
  cfg: OpenClawConfig, 
  accountId: string
): ResolvedPITBotAccount {
  const log = createLogger(MODULE);
  
  const pit = cfg.channels?.["zhidui-channel"] as PITChannelConfig | undefined;

  // 如果没有配置，返回默认值
  if (!pit) {
    log.warn(`No zhidui-channel configuration found, using defaults`);
    return {
      accountId,
      name: undefined,
      enabled: false,
      routerUrl: "",
      authToken: "",
      secretSource: "none",
      config: {
        enabled: false,
        reconnectInterval: 5000,
        heartbeatInterval: 30000,
        heartbeatTimeout: 10000,
        ackTimeout: 30000,
        maxQueueSize: 100,
      },
    };
  }

  // 获取全局默认配置
  const defaults: PITBotAccountConfig = {
    enabled: pit.enabled ?? true,
    routerUrl: pit.routerUrl,
    authToken: pit.authToken,
    name: pit.name,
    reconnectInterval: pit.reconnectInterval ?? 5000,
    heartbeatInterval: pit.heartbeatInterval ?? 30000,
    heartbeatTimeout: pit.heartbeatTimeout ?? 10000,
    ackTimeout: pit.ackTimeout ?? 30000,
    maxQueueSize: pit.maxQueueSize ?? 100,
  };

  // 获取特定账户配置
  let accountConfig: PITBotAccountConfig = {};
  
  if (pit.accounts && typeof pit.accounts === "object") {
    const specificConfig = pit.accounts[accountId];
    if (specificConfig && typeof specificConfig === "object") {
      accountConfig = specificConfig;
    }
  }

  // 合并配置（账户配置覆盖默认配置）
  const mergedConfig: PITBotAccountConfig = {
    ...defaults,
    ...accountConfig,
  };

  // 解析认证 Token
  const { authToken, secretSource } = resolveAuthToken(mergedConfig.authToken, accountId, log);

  // 验证必需字段
  const routerUrl = mergedConfig.routerUrl;
  if (!routerUrl || typeof routerUrl !== "string") {
    log.warn(`No routerUrl configured for account ${accountId}`);
  }

  return {
    accountId,
    name: mergedConfig.name,
    enabled: mergedConfig.enabled ?? true,
    routerUrl: routerUrl ?? "",
    authToken: authToken ?? "",
    secretSource,
    config: mergedConfig,
  };
}

/**
 * 应用 PIT Bot 账户配置
 * @param cfg OpenClaw 配置
 * @param accountId 账户 ID
 * @param config 新配置
 */
export function applyPITBotAccountConfig(
  cfg: OpenClawConfig, 
  accountId: string, 
  config: Partial<PITBotAccountConfig>
): void {
  // No-op for now - configuration is managed by OpenClaw
  console.log(`[zhidui-channel] applyAccountConfig called for ${accountId}:`, config);
}

/**
 * 解析认证 Token
 * 支持环境变量引用和环境变量名
 */
function resolveAuthToken(
  configToken: string | undefined, 
  accountId: string,
  log: { warn: (msg: string) => void }
): { authToken: string | null; secretSource: "config" | "env" | "none" } {
  // 1. 如果配置中直接设置了 Token
  if (configToken && typeof configToken === "string") {
    // 检查是否是环境变量引用 ${VAR_NAME}
    const envMatch = configToken.match(/^\$\{(.+)\}$/);
    if (envMatch) {
      const envVar = envMatch[1];
      const token = process.env[envVar];
      if (!token) {
        log.warn(`Environment variable ${envVar} is not set for account ${accountId}`);
        return { authToken: null, secretSource: "env" };
      }
      return { authToken: token, secretSource: "env" };
    }
    return { authToken: configToken, secretSource: "config" };
  }

  // 2. 尝试从标准环境变量名获取
  const envVarName = accountId === DEFAULT_ACCOUNT_ID 
    ? "PIT_ROUTER_TOKEN" 
    : `PIT_ROUTER_TOKEN_${accountId.toUpperCase()}`;
  
  const envToken = process.env[envVarName];
  if (envToken) {
    return { authToken: envToken, secretSource: "env" };
  }

  // 3. 无 Token
  return { authToken: null, secretSource: "none" };
}

/**
 * 验证配置
 */
export function validateConfig(config: PITBotAccountConfig | undefined): { valid: boolean; errors: string[] } {
  const errors: string[] = [];

  if (!config) {
    errors.push("Configuration is required");
    return { valid: false, errors };
  }

  if (!config.routerUrl) {
    errors.push("routerUrl is required");
  } else if (!isValidUrl(config.routerUrl)) {
    errors.push(`routerUrl is invalid: ${config.routerUrl}`);
  }

  if (config.reconnectInterval !== undefined && config.reconnectInterval < 1000) {
    errors.push("reconnectInterval must be at least 1000ms");
  }

  if (config.heartbeatInterval !== undefined && config.heartbeatInterval < 1000) {
    errors.push("heartbeatInterval must be at least 1000ms");
  }

  return {
    valid: errors.length === 0,
    errors,
  };
}

/**
 * 验证 URL
 */
function isValidUrl(url: string): boolean {
  try {
    new URL(url);
    return true;
  } catch {
    return false;
  }
}