login method

Future<void> login()

Ensures the user is logged into Firebase and prompts for account selection if multiple accounts are available.

This method provides:

• Interactive account selection.
• Support for adding new accounts (--reauth flow).
• Account switching with automatic session cleanup.
• Logout functionality.

Implementation

Future<void> login() async {
  print('🔐 Checking Firebase account...\n');

  try {
    final result = await runWithResult('firebase', ['login:list']);
    final output = result.stdout.toString() + result.stderr.toString();

    final emailRegex =
        RegExp(r'[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}');
    final lines = output.split('\n');
    final allAccounts = <String>[];
    String? currentAccount;

    for (var line in lines) {
      final match = emailRegex.firstMatch(line);
      if (match != null) {
        final email = match.group(0)!;
        if (!allAccounts.contains(email)) {
          allAccounts.add(email);
        }
        // Firebase CLI marks active account with * or (current)
        // Or if it just says "Logged in as email"
        if (line.contains('*') ||
            line.contains('(current)') ||
            line.contains('Logged in as $email')) {
          currentAccount = email;
        }
      }
    }

    // Fallback: If only one account exists, it must be the current one
    if (allAccounts.length == 1 && currentAccount == null) {
      currentAccount = allAccounts.first;
    }

    // If no accounts, need to log in
    if (allAccounts.isEmpty) {
      print('❌ No Firebase accounts found');
      print('📦 Triggering interactive login...\n');
      await runInteractive('firebase', ['login']);
      return;
    }

    // If we have accounts, ask which one to use
    final prompt = PromptService();
    final options = [
      ...allAccounts,
      '+ Add a new account',
      '❌ Logout from active account'
    ];

    print('👤 Currently logged in accounts:');
    for (int i = 0; i < allAccounts.length; i++) {
      final isCurrent = allAccounts[i] == currentAccount;
      print('  ${i + 1}. ${allAccounts[i]} ${isCurrent ? "⭐️ (active)" : ""}');
    }
    print('');

    final index =
        prompt.select('Select Google account to use for this project', options);

    if (index == allAccounts.length) {
      // Add new account
      print('📦 Adding new account...\n');

      // 🔥 CRITICAL: Logout from current to prevent the "login_hint" in URL
      if (currentAccount != null) {
        print('🧹 Clearing current session hint ($currentAccount)...');
        await run('firebase', ['logout', currentAccount]);
      }

      print('🔄 Opening browser for fresh login...\n');
      await runInteractive('firebase', ['login']);

      // Refresh the check to show the new account list
      print('\n🔄 Refreshing account list...');
      await login();
      return;
    } else if (index == allAccounts.length + 1) {
      // Logout
      if (currentAccount != null) {
        print('🚫 Logging out from $currentAccount...\n');
        await run('firebase', ['logout', currentAccount]);
        print('✅ Logged out successfully');
        await login(); // Refresh
        return;
      } else {
        print('🚫 Logging out from all accounts...\n');
        await run('firebase', ['logout']);
        await login();
        return;
      }
    } else {
      final selectedEmail = allAccounts[index];
      if (selectedEmail != currentAccount) {
        print('🔄 Switching to account: $selectedEmail...\n');
        print('⚠️ Switching requires logging out of $currentAccount first.');

        if (currentAccount != null) {
           await run('firebase', ['logout', currentAccount]);
        }

        print('📦 Now please log in to $selectedEmail in the browser...\n');
        await runInteractive('firebase', ['login']);

        await login(); // Re-verify to confirm switch worked
        return;
      } else {
        print('✅ Using active account: $selectedEmail');
      }
    }

  } catch (e) {
    print('❌ Firebase account check failed');
    rethrow;
  }
}