import * as plugins from './mod.plugins.js';

export type TPackageManager = 'npm' | 'yarn' | 'pnpm';

export interface IInstalledPackage {
  name: string;
  version: string;
  packageManager: TPackageManager;
}

export interface IPackageUpdateInfo {
  name: string;
  currentVersion: string;
  latestVersion: string;
  packageManager: TPackageManager;
  needsUpdate: boolean;
}

export interface IPackageManagerInfo {
  name: TPackageManager;
  available: boolean;
  detectionMethod?: 'which' | 'version-command';
  path?: string;
  currentVersion?: string;
  latestVersion?: string | null;
  needsUpdate?: boolean;
}

export class PackageManagerUtil {
  private shell = new plugins.smartshell.Smartshell({
    executor: 'bash',
  });

  /**
   * Check if a package manager is available on the system
   * Uses multiple detection methods for robustness across different shell contexts
   */
  public async isAvailable(pm: TPackageManager, verbose = false): Promise<boolean> {
    const info = await this.detectPackageManager(pm, verbose);
    return info.available;
  }

  /**
   * Detect a package manager and return detailed info
   */
  public async detectPackageManager(pm: TPackageManager, verbose = false): Promise<IPackageManagerInfo> {
    const info: IPackageManagerInfo = { name: pm, available: false };

    // Primary method: try 'which' command
    try {
      const whichResult = await this.shell.execSilent(`which ${pm} 2>/dev/null`);
      if (whichResult.exitCode === 0 && whichResult.stdout.trim()) {
        info.available = true;
        info.detectionMethod = 'which';
        info.path = whichResult.stdout.trim();
        if (verbose) {
          console.log(`  Checking ${pm}... found via 'which' at ${info.path}`);
        }
        return info;
      }
    } catch {
      // Continue to fallback
    }

    // Fallback method: try running pm --version directly
    // This can find PMs that are available but not in PATH for 'which'
    try {
      const versionResult = await this.shell.execSilent(`${pm} --version 2>/dev/null`);
      if (versionResult.exitCode === 0 && versionResult.stdout.trim()) {
        info.available = true;
        info.detectionMethod = 'version-command';
        if (verbose) {
          console.log(`  Checking ${pm}... found via '--version' (which failed)`);
        }
        return info;
      }
    } catch {
      // Not available
    }

    if (verbose) {
      console.log(`  Checking ${pm}... not found`);
    }
    return info;
  }

  /**
   * Get the current and latest version of a package manager
   */
  public async getPackageManagerVersion(pm: TPackageManager): Promise<{ current: string; latest: string | null }> {
    let current = 'unknown';
    let latest: string | null = null;

    // Get current version
    try {
      const result = await this.shell.execSilent(`${pm} --version 2>/dev/null`);
      if (result.exitCode === 0 && result.stdout.trim()) {
        // Parse version from output - handle different formats
        const output = result.stdout.trim();
        // npm: "10.2.0", pnpm: "8.15.0", yarn: "1.22.19"
        // Some may include prefix like "v1.22.19"
        const versionMatch = output.match(/(\d+\.\d+\.\d+)/);
        if (versionMatch) {
          current = versionMatch[1];
        }
      }
    } catch {
      // Keep as unknown
    }

    // Get latest version from npm registry
    try {
      const result = await this.shell.execSilent(`npm view ${pm} version 2>/dev/null`);
      if (result.exitCode === 0 && result.stdout.trim()) {
        latest = result.stdout.trim();
      }
    } catch {
      // Keep as null
    }

    return { current, latest };
  }

  /**
   * Get all globally installed @git.zone packages for a package manager
   */
  public async getInstalledPackages(pm: TPackageManager): Promise<IInstalledPackage[]> {
    const packages: IInstalledPackage[] = [];

    try {
      let result;
      switch (pm) {
        case 'npm':
          result = await this.shell.execSilent('npm list -g --depth=0 --json 2>/dev/null || true');
          break;
        case 'yarn':
          result = await this.shell.execSilent('yarn global list --depth=0 --json 2>/dev/null || true');
          break;
        case 'pnpm':
          result = await this.shell.execSilent('pnpm list -g --depth=0 --json 2>/dev/null || true');
          break;
      }

      const output = result.stdout.trim();
      if (!output) {
        return packages;
      }

      if (pm === 'npm') {
        try {
          const data = JSON.parse(output);
          const deps = data.dependencies || {};
          for (const [name, info] of Object.entries(deps)) {
            if (name.startsWith('@git.zone/')) {
              packages.push({
                name,
                version: (info as any).version || 'unknown',
                packageManager: pm,
              });
            }
          }
        } catch {
          // JSON parse failed
        }
      } else if (pm === 'pnpm') {
        // pnpm returns an array of objects
        try {
          const data = JSON.parse(output);
          // Handle array format from pnpm
          const dataArray = Array.isArray(data) ? data : [data];
          for (const item of dataArray) {
            const deps = item.dependencies || {};
            for (const [name, info] of Object.entries(deps)) {
              if (name.startsWith('@git.zone/')) {
                packages.push({
                  name,
                  version: (info as any).version || 'unknown',
                  packageManager: pm,
                });
              }
            }
          }
        } catch {
          // JSON parse failed
        }
      } else if (pm === 'yarn') {
        // Yarn global list --json outputs multiple JSON lines
        const lines = output.split('\n').filter(l => l.trim());
        for (const line of lines) {
          try {
            const data = JSON.parse(line);
            if (data.type === 'tree' && data.data && data.data.trees) {
              for (const tree of data.data.trees) {
                const name = tree.name?.split('@')[0] || '';
                if (name.startsWith('@git.zone/')) {
                  const version = tree.name?.split('@').pop() || 'unknown';
                  packages.push({
                    name,
                    version,
                    packageManager: pm,
                  });
                }
              }
            }
          } catch {
            // Skip invalid JSON lines
          }
        }
      }
    } catch {
      // Command failed, return empty array
    }

    return packages;
  }

  /**
   * Get the latest version of a package from npm registry
   * Tries private registry (verdaccio.lossless.digital) first via API, then falls back to public npm
   */
  public async getLatestVersion(packageName: string): Promise<string | null> {
    // URL-encode the package name for scoped packages (@scope/name -> @scope%2fname)
    const encodedName = packageName.replace('/', '%2f');

    // Try private registry first via direct API call (npm view doesn't work reliably)
    try {
      const result = await this.shell.execSilent(
        `curl -sf "https://verdaccio.lossless.digital/${encodedName}" 2>/dev/null`
      );
      if (result.exitCode === 0 && result.stdout.trim()) {
        const data = JSON.parse(result.stdout.trim());
        if (data['dist-tags']?.latest) {
          return data['dist-tags'].latest;
        }
      }
    } catch {
      // Continue to public registry
    }

    // Fall back to public npm
    try {
      const result = await this.shell.execSilent(`npm view ${packageName} version 2>/dev/null`);
      if (result.exitCode === 0 && result.stdout.trim()) {
        return result.stdout.trim();
      }
    } catch {
      // Command failed
    }
    return null;
  }

  /**
   * Execute an update for a package using the specified package manager
   */
  public async executeUpdate(pm: TPackageManager, packageName: string): Promise<boolean> {
    let command: string;

    switch (pm) {
      case 'npm':
        command = `npm install -g ${packageName}@latest`;
        break;
      case 'yarn':
        command = `yarn global add ${packageName}@latest`;
        break;
      case 'pnpm':
        command = `pnpm add -g ${packageName}@latest`;
        break;
    }

    console.log(`  Updating ${packageName} via ${pm}...`);

    try {
      const result = await this.shell.exec(command);
      return result.exitCode === 0;
    } catch {
      return false;
    }
  }

  /**
   * Compare two semver versions
   * Returns true if latest > current
   */
  public isNewerVersion(current: string, latest: string): boolean {
    const cleanVersion = (v: string) => v.replace(/^[^\d]*/, '');
    const currentClean = cleanVersion(current);
    const latestClean = cleanVersion(latest);

    const currentParts = currentClean.split('.').map(n => parseInt(n, 10) || 0);
    const latestParts = latestClean.split('.').map(n => parseInt(n, 10) || 0);

    for (let i = 0; i < Math.max(currentParts.length, latestParts.length); i++) {
      const curr = currentParts[i] || 0;
      const lat = latestParts[i] || 0;
      if (lat > curr) return true;
      if (lat < curr) return false;
    }

    return false;
  }
}