import { loadConfig } from '../config/index.js';
import type { Config } from '../config/index.js';
import { resolve, dirname, join } from 'path';
import { homedir } from 'os';
import { existsSync, readFileSync } from 'fs';

function loadEnvFileIfPresent(): void {
  const envFile = process.env.FLYNN_ENV_FILE ?? resolve(homedir(), '.config/flynn/cloud.env');
  if (!existsSync(envFile)) {
    return;
  }

  const raw = readFileSync(envFile, 'utf-8');
  for (const line of raw.split(/\r?\n/)) {
    const trimmed = line.trim();
    if (!trimmed || trimmed.startsWith('#')) {
      continue;
    }

    const idx = trimmed.indexOf('=');
    if (idx <= 0) {
      continue;
    }

    const key = trimmed.slice(0, idx).trim();
    const value = trimmed.slice(idx + 1);
    if (!key) {
      continue;
    }

    // Don't override existing env vars.
    if (process.env[key] === undefined) {
      process.env[key] = value;
    }
  }
}

/** Get the config file path from env or default location. */
export function getConfigPath(): string {
  return process.env.FLYNN_CONFIG ?? resolve(homedir(), '.config/flynn/config.yaml');
}

/** Get the data directory path (FLYNN_DATA_DIR overrides default for Docker/custom deployments). */
export function getDataDir(): string {
  return process.env.FLYNN_DATA_DIR ?? resolve(homedir(), '.local/share/flynn');
}

/**
 * Resolve overlay config path from FLYNN_ENV.
 * If FLYNN_ENV is set, returns {configDir}/{FLYNN_ENV}.yaml relative to the base config file.
 * Returns undefined if FLYNN_ENV is not set.
 * Does NOT check if the file exists — caller decides error handling.
 */
export function resolveOverlayPath(basePath: string): string | undefined {
  const env = process.env.FLYNN_ENV;
  if (!env) {return undefined;}
  const configDir = dirname(basePath);
  return join(configDir, `${env}.yaml`);
}

/** Load config without throwing. Returns { config } or { error }. */
export function loadConfigSafe(configPath?: string): { config?: Config; error?: string } {
  const path = configPath ?? getConfigPath();
  try {
    loadEnvFileIfPresent();
    const overlayPath = resolveOverlayPath(path);
    const config = loadConfig(path, overlayPath);
    return { config };
  } catch (error) {
    const message = error instanceof Error ? error.message : String(error);
    return { error: `Failed to load config from ${path}: ${message}` };
  }
}

/** Deep-clone config and replace sensitive fields with '***'. */
export function redactSecrets(config: Record<string, unknown>): Record<string, unknown> {
  const sensitiveKeys = ['bot_token', 'api_key', 'auth_token', 'access_token'];

  function redact(obj: unknown): unknown {
    if (obj === null || obj === undefined) {return obj;}
    if (Array.isArray(obj)) {return obj.map(redact);}
    if (typeof obj === 'object') {
      const result: Record<string, unknown> = {};
      for (const [key, value] of Object.entries(obj as Record<string, unknown>)) {
        if (sensitiveKeys.includes(key) && typeof value === 'string') {
          result[key] = '***';
        } else {
          result[key] = redact(value);
        }
      }
      return result;
    }
    return obj;
  }

  return redact(config) as Record<string, unknown>;
}

/** Format output for terminal display. */
export function formatStatus(
  status: 'pass' | 'fail' | 'warn' | 'skip',
  label: string,
  detail?: string,
): string {
  const icons: Record<string, string> = {
    pass: '\x1b[32m[PASS]\x1b[0m',
    fail: '\x1b[31m[FAIL]\x1b[0m',
    warn: '\x1b[33m[WARN]\x1b[0m',
    skip: '\x1b[2m[SKIP]\x1b[0m',
  };
  const suffix = detail ? ` ${detail}` : '';
  return `${icons[status]} ${label}${suffix}`;
}