const path = require('node:path');
const { BaseIdeSetup } = require('./_base-ide');
const chalk = require('chalk');
const inquirer = require('inquirer');
const { AgentCommandGenerator } = require('./shared/agent-command-generator');

/**
 * GitHub Copilot setup handler
 * Creates chat modes in .github/chatmodes/ and configures VS Code settings
 */
class GitHubCopilotSetup extends BaseIdeSetup {
  constructor() {
    super('github-copilot', 'GitHub Copilot', true); // preferred IDE
    this.configDir = '.github';
    this.chatmodesDir = 'chatmodes';
    this.vscodeDir = '.vscode';
  }

  /**
   * Collect configuration choices before installation
   * @param {Object} options - Configuration options
   * @returns {Object} Collected configuration
   */
  async collectConfiguration(options = {}) {
    const config = {};

    console.log('\n' + chalk.blue('  🔧 VS Code Settings Configuration'));
    console.log(chalk.dim('  GitHub Copilot works best with specific settings\n'));

    const response = await inquirer.prompt([
      {
        type: 'list',
        name: 'configChoice',
        message: 'How would you like to configure VS Code settings?',
        choices: [
          { name: 'Use recommended defaults (fastest)', value: 'defaults' },
          { name: 'Configure each setting manually', value: 'manual' },
          { name: 'Skip settings configuration', value: 'skip' },
        ],
        default: 'defaults',
      },
    ]);
    config.vsCodeConfig = response.configChoice;

    if (response.configChoice === 'manual') {
      config.manualSettings = await inquirer.prompt([
        {
          type: 'input',
          name: 'maxRequests',
          message: 'Maximum requests per session (1-50)?',
          default: '15',
          validate: (input) => {
            const num = parseInt(input);
            return (num >= 1 && num <= 50) || 'Enter 1-50';
          },
        },
        {
          type: 'confirm',
          name: 'runTasks',
          message: 'Allow running workspace tasks?',
          default: true,
        },
        {
          type: 'confirm',
          name: 'mcpDiscovery',
          message: 'Enable MCP server discovery?',
          default: true,
        },
        {
          type: 'confirm',
          name: 'autoFix',
          message: 'Enable automatic error fixing?',
          default: true,
        },
        {
          type: 'confirm',
          name: 'autoApprove',
          message: 'Auto-approve tools (less secure)?',
          default: false,
        },
      ]);
    }

    return config;
  }

  /**
   * Setup GitHub Copilot configuration
   * @param {string} projectDir - Project directory
   * @param {string} bmadDir - BMAD installation directory
   * @param {Object} options - Setup options
   */
  async setup(projectDir, bmadDir, options = {}) {
    console.log(chalk.cyan(`Setting up ${this.name}...`));

    // Configure VS Code settings using pre-collected config if available
    const config = options.preCollectedConfig || {};
    await this.configureVsCodeSettings(projectDir, { ...options, ...config });

    // Create .github/chatmodes directory
    const githubDir = path.join(projectDir, this.configDir);
    const chatmodesDir = path.join(githubDir, this.chatmodesDir);
    await this.ensureDir(chatmodesDir);

    // Clean up any existing BMAD files before reinstalling
    await this.cleanup(projectDir);

    // Generate agent launchers
    const agentGen = new AgentCommandGenerator(this.bmadFolderName);
    const { artifacts: agentArtifacts } = await agentGen.collectAgentArtifacts(bmadDir, options.selectedModules || []);

    // Create chat mode files with bmad- prefix
    let modeCount = 0;
    for (const artifact of agentArtifacts) {
      const content = artifact.content;
      const chatmodeContent = await this.createChatmodeContent({ module: artifact.module, name: artifact.name }, content);

      // Use bmad- prefix: bmad-agent-{module}-{name}.chatmode.md
      const targetPath = path.join(chatmodesDir, `bmad-agent-${artifact.module}-${artifact.name}.chatmode.md`);
      await this.writeFile(targetPath, chatmodeContent);
      modeCount++;

      console.log(chalk.green(`  ✓ Created chat mode: bmad-agent-${artifact.module}-${artifact.name}`));
    }

    console.log(chalk.green(`✓ ${this.name} configured:`));
    console.log(chalk.dim(`  - ${modeCount} chat modes created`));
    console.log(chalk.dim(`  - Chat modes directory: ${path.relative(projectDir, chatmodesDir)}`));
    console.log(chalk.dim(`  - VS Code settings configured`));
    console.log(chalk.dim('\n  Chat modes available in VS Code Chat view'));

    return {
      success: true,
      chatmodes: modeCount,
      settings: true,
    };
  }

  /**
   * Configure VS Code settings for GitHub Copilot
   */
  async configureVsCodeSettings(projectDir, options) {
    const fs = require('fs-extra');
    const vscodeDir = path.join(projectDir, this.vscodeDir);
    const settingsPath = path.join(vscodeDir, 'settings.json');

    await this.ensureDir(vscodeDir);

    // Read existing settings
    let existingSettings = {};
    if (await fs.pathExists(settingsPath)) {
      try {
        const content = await fs.readFile(settingsPath, 'utf8');
        existingSettings = JSON.parse(content);
        console.log(chalk.yellow('  Found existing .vscode/settings.json'));
      } catch {
        console.warn(chalk.yellow('  Could not parse settings.json, creating new'));
      }
    }

    // Use pre-collected configuration or skip if not available
    let configChoice = options.vsCodeConfig;
    if (!configChoice) {
      // If no pre-collected config, skip configuration
      console.log(chalk.yellow('  ⚠ No configuration collected, skipping VS Code settings'));
      return;
    }

    if (configChoice === 'skip') {
      console.log(chalk.yellow('  ⚠ Skipping VS Code settings'));
      return;
    }

    let bmadSettings = {};

    if (configChoice === 'defaults') {
      bmadSettings = {
        'chat.agent.enabled': true,
        'chat.agent.maxRequests': 15,
        'github.copilot.chat.agent.runTasks': true,
        'chat.mcp.discovery.enabled': true,
        'github.copilot.chat.agent.autoFix': true,
        'chat.tools.autoApprove': false,
      };
      console.log(chalk.green('  ✓ Using recommended defaults'));
    } else {
      // Manual configuration - use pre-collected settings
      const manual = options.manualSettings || {};

      bmadSettings = {
        'chat.agent.enabled': true,
        'chat.agent.maxRequests': parseInt(manual.maxRequests || 15),
        'github.copilot.chat.agent.runTasks': manual.runTasks === undefined ? true : manual.runTasks,
        'chat.mcp.discovery.enabled': manual.mcpDiscovery === undefined ? true : manual.mcpDiscovery,
        'github.copilot.chat.agent.autoFix': manual.autoFix === undefined ? true : manual.autoFix,
        'chat.tools.autoApprove': manual.autoApprove || false,
      };
    }

    // Merge settings (existing take precedence)
    const mergedSettings = { ...bmadSettings, ...existingSettings };

    // Write settings
    await fs.writeFile(settingsPath, JSON.stringify(mergedSettings, null, 2));
    console.log(chalk.green('  ✓ VS Code settings configured'));
  }

  /**
   * Create chat mode content
   */
  async createChatmodeContent(agent, content) {
    // Extract metadata from launcher frontmatter if present
    const descMatch = content.match(/description:\s*"([^"]+)"/);
    const title = descMatch ? descMatch[1] : this.formatTitle(agent.name);

    const description = `Activates the ${title} agent persona.`;

    // Strip any existing frontmatter from the content
    const frontmatterRegex = /^---\s*\n[\s\S]*?\n---\s*\n/;
    let cleanContent = content;
    if (frontmatterRegex.test(content)) {
      cleanContent = content.replace(frontmatterRegex, '').trim();
    }

    // Available GitHub Copilot tools (November 2025 - Official VS Code Documentation)
    // Reference: https://code.visualstudio.com/docs/copilot/reference/copilot-vscode-features#_chat-tools
    const tools = [
      'changes', // List of source control changes
      'codebase', // Perform code search in workspace
      'createDirectory', // Create new directory in workspace
      'createFile', // Create new file in workspace
      'editFiles', // Apply edits to files in workspace
      'fetch', // Fetch content from web page
      'fileSearch', // Search files using glob patterns
      'githubRepo', // Perform code search in GitHub repo
      'listDirectory', // List files in a directory
      'problems', // Add workspace issues from Problems panel
      'readFile', // Read content of a file in workspace
      'runInTerminal', // Run shell command in integrated terminal
      'runTask', // Run existing task in workspace
      'runTests', // Run unit tests in workspace
      'runVscodeCommand', // Run VS Code command
      'search', // Enable file searching in workspace
      'searchResults', // Get search results from Search view
      'terminalLastCommand', // Get last terminal command and output
      'terminalSelection', // Get current terminal selection
      'testFailure', // Get unit test failure information
      'textSearch', // Find text in files
      'usages', // Find references and navigate definitions
    ];

    let chatmodeContent = `---
description: "${description.replaceAll('"', String.raw`\"`)}"
tools: ${JSON.stringify(tools)}
---

# ${title} Agent

${cleanContent}

`;

    return chatmodeContent;
  }

  /**
   * Format name as title
   */
  formatTitle(name) {
    return name
      .split('-')
      .map((word) => word.charAt(0).toUpperCase() + word.slice(1))
      .join(' ');
  }

  /**
   * Cleanup GitHub Copilot configuration - surgically remove only BMAD files
   */
  async cleanup(projectDir) {
    const fs = require('fs-extra');
    const chatmodesDir = path.join(projectDir, this.configDir, this.chatmodesDir);

    if (await fs.pathExists(chatmodesDir)) {
      // Only remove files that start with bmad- prefix
      const files = await fs.readdir(chatmodesDir);
      let removed = 0;

      for (const file of files) {
        if (file.startsWith('bmad-') && file.endsWith('.chatmode.md')) {
          await fs.remove(path.join(chatmodesDir, file));
          removed++;
        }
      }

      if (removed > 0) {
        console.log(chalk.dim(`  Cleaned up ${removed} existing BMAD chat modes`));
      }
    }
  }
}

module.exports = { GitHubCopilotSetup };