const express = require('express');
const fs = require('fs').promises;
const path = require('path');

const paths = require('../utils/paths');
const serverManager = require('../utils/shared-server-manager');
const ConfigManager = require('../utils/config-manager');
const ConfigParser = require('../utils/config-parser');
const appConfig = require('../utils/app-config');

const router = express.Router();

// Create global config manager instance
const configManager = new ConfigManager();

// Initialize server manager with socket.io when available
let io = null;

function setSocketIO(socketInstance) {
  io = socketInstance;
  
  // Attach server manager events to socket.io
  serverManager.on('log', (logEntry) => {
    if (io) {
      io.emit('server:log', logEntry);
    }
  });
  
  serverManager.on('stats', (stats) => {
    if (io) {
      io.emit('server:stats', stats);
    }
  });

  serverManager.on('status', (status) => {
    if (io) {
      io.emit('server:status', status);
    }
  });

  serverManager.on('exit', (exitInfo) => {
    if (io) {
      // Broadcast status immediately when server exits
      serverManager.getServerStatus().then(status => {
        io.emit('server:status', status);
      });
    }
  });
}

// Server status endpoint
router.get('/server/status', async (req, res) => {
  try {
    const status = await serverManager.getServerStatus();
    
    // For all running servers, get player list from debug.txt
    let playerList = [];
    if (status.isRunning) {
      const playerData = await serverManager.getExternalServerPlayerData();
      playerList = playerData.players;
      
      // Also update the server stats with current player count
      serverManager.serverStats.players = playerData.count;
      
      // Emit player list via WebSocket if available
      if (io) {
        io.emit('server:players', playerList);
      }
    }
    
    const isExternal = serverManager.serverProcess?.external || false;
    
    res.json({
      ...status,
      players: playerList.length, // Override with actual player count
      playerList: playerList,
      // Add simple string status for UI
      statusText: status.isRunning ? 'running' : 'stopped',
      // Include external server information
      isExternal: isExternal
    });
  } catch (error) {
    console.error('API: Server status error:', error);
    res.status(500).json({ 
      error: error.message,
      statusText: 'stopped',
      isRunning: false,
      isReady: false,
      playerList: []
    });
  }
});

// Start server
router.post('/server/start', async (req, res) => {
  try {
    const { worldName } = req.body;
    console.log('Server start requested with world:', worldName);
    const result = await serverManager.startServer(worldName);
    res.json(result);
  } catch (error) {
    console.error('Server start error:', error);
    res.status(500).json({ 
      success: false, 
      error: error.message 
    });
  }
});

// Stop server
router.post('/server/stop', async (req, res) => {
  try {
    const { force = false } = req.body;
    const result = await serverManager.stopServer(force);
    res.json(result);
  } catch (error) {
    res.status(500).json({ 
      success: false, 
      error: error.message 
    });
  }
});

// Restart server
router.post('/server/restart', async (req, res) => {
  try {
    const { worldName } = req.body;
    const result = await serverManager.restartServer(worldName);
    res.json(result);
  } catch (error) {
    res.status(500).json({ 
      success: false, 
      error: error.message 
    });
  }
});

// Send command to server
router.post('/server/command', async (req, res) => {
  try {
    const { command } = req.body;
    if (!command || typeof command !== 'string') {
      return res.status(400).json({ error: 'Command is required' });
    }
    
    const result = await serverManager.sendCommand(command.trim());
    res.json(result);
  } catch (error) {
    res.status(500).json({ 
      success: false, 
      error: error.message 
    });
  }
});

// Get server logs
router.get('/server/logs', async (req, res) => {
  try {
    const { lines = 500, format = 'text' } = req.query;
    const logs = serverManager.getLogs(parseInt(lines));
    
    if (format === 'json') {
      res.json(logs);
    } else {
      // Return as downloadable text file
      const logText = logs.map(log => 
        `[${log.timestamp}] ${log.type.toUpperCase()}: ${log.content}`
      ).join('\n');
      
      res.setHeader('Content-Disposition', 'attachment; filename=server-logs.txt');
      res.setHeader('Content-Type', 'text/plain');
      res.send(logText);
    }
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Get server info
router.get('/server/info', async (req, res) => {
  try {
    const info = await serverManager.getServerInfo();
    res.json(info);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Configuration endpoints

// Get all configuration sections
router.get('/config/sections', async (req, res) => {
  try {
    const sections = configManager.getAllSettings();
    res.json(sections);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Get current configuration
router.get('/config', async (req, res) => {
  try {
    // Use the new configuration schema approach instead of ConfigManager
    const configSchema = {
      System: {
        data_directory: {
          type: 'string',
          default: '',
          description: 'Luanti data directory path (leave empty for auto-detection)'
        }
      },
      Server: {
        port: {
          type: 'number',
          default: 30000,
          description: 'Port for server to listen on'
        },
        server_name: {
          type: 'string',
          default: 'Luanti Server',
          description: 'Name of the server'
        },
        server_description: {
          type: 'string',
          default: 'A Luanti server',
          description: 'Server description'
        },
        server_announce: {
          type: 'boolean',
          default: false,
          description: 'Announce server to server list'
        },
        max_users: {
          type: 'number',
          default: 20,
          description: 'Maximum number of users'
        }
      },
      World: {
        creative_mode: {
          type: 'boolean',
          default: false,
          description: 'Enable creative mode by default'
        },
        enable_damage: {
          type: 'boolean',
          default: true,
          description: 'Enable player damage by default'
        },
        enable_pvp: {
          type: 'boolean',
          default: true,
          description: 'Enable player vs player combat by default'
        },
        default_game: {
          type: 'string',
          default: 'minetest_game',
          description: 'Default game to use for new worlds'
        },
        time_speed: {
          type: 'number',
          default: 72,
          description: 'Time speed (72 = normal, higher = faster)'
        }
      },
      Security: {
        disallow_empty_password: {
          type: 'boolean',
          default: false,
          description: 'Disallow empty passwords'
        },
        strict_protocol_version_checking: {
          type: 'boolean',
          default: false,
          description: 'Strict protocol version checking'
        }
      },
      Performance: {
        dedicated_server_step: {
          type: 'number',
          default: 0.1,
          description: 'Server step time in seconds'
        },
        num_emerge_threads: {
          type: 'number',
          default: 1,
          description: 'Number of emerge threads'
        },
        server_map_save_interval: {
          type: 'number',
          default: 15.3,
          description: 'Map save interval in seconds'
        },
        max_block_send_distance: {
          type: 'number',
          default: 12,
          description: 'Maximum block send distance'
        }
      },
      Network: {
        server_address: {
          type: 'string',
          default: '',
          description: 'IP address to bind to (empty for all interfaces)'
        },
        server_dedicated: {
          type: 'boolean',
          default: false,
          description: 'Run as dedicated server'
        }
      },
      Advanced: {
        max_simultaneous_block_sends_per_client: {
          type: 'number',
          default: 40,
          description: 'Maximum simultaneous block sends per client'
        }
      }
    };
    
    // Load both Luanti config and app config
    const luantiConfig = await ConfigParser.parseConfig(paths.configFile);
    await appConfig.load();
    
    // Combine configs for display
    const combinedConfig = {
      ...luantiConfig,
      data_directory: appConfig.getDataDirectory()
    };
    
    // Organize schema into sections with proper structure for frontend
    const sections = {};
    for (const [sectionName, sectionFields] of Object.entries(configSchema)) {
      sections[sectionName] = {
        description: sectionName + ' configuration settings',
        settings: sectionFields
      };
    }
    
    res.json({
      current: combinedConfig,
      sections: sections,
      schema: configSchema
    });
  } catch (error) {
    console.error('Error getting config via API:', error);
    res.status(500).json({ error: error.message });
  }
});

// Update configuration
router.post('/config', async (req, res) => {
  try {
    const { settings } = req.body;
    
    if (!settings || typeof settings !== 'object') {
      return res.status(400).json({ error: 'Settings object is required' });
    }
    
    // Validate all settings
    const validationErrors = [];
    const validatedSettings = {};
    
    for (const [key, value] of Object.entries(settings)) {
      const validation = configManager.validateSetting(key, value);
      if (validation.valid) {
        validatedSettings[key] = validation.value;
      } else {
        validationErrors.push({ key, error: validation.error });
      }
    }
    
    if (validationErrors.length > 0) {
      return res.status(400).json({ 
        error: 'Validation failed', 
        details: validationErrors 
      });
    }
    
    const result = await configManager.updateSettings(validatedSettings);
    res.json(result);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Update single configuration setting
router.put('/config/:key', async (req, res) => {
  try {
    const { key } = req.params;
    const { value } = req.body;
    
    const validation = configManager.validateSetting(key, value);
    if (!validation.valid) {
      return res.status(400).json({ error: validation.error });
    }
    
    const result = await configManager.updateSetting(key, validation.value);
    res.json(result);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Reset configuration section to defaults
router.post('/config/reset/:section?', async (req, res) => {
  try {
    const { section } = req.params;
    const result = await configManager.resetToDefaults(section);
    res.json(result);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Get setting information
router.get('/config/setting/:key', async (req, res) => {
  try {
    const { key } = req.params;
    const info = configManager.getSettingInfo(key);
    
    if (!info) {
      return res.status(404).json({ error: 'Setting not found' });
    }
    
    res.json(info);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// Worlds endpoints (basic)
router.get('/worlds', async (req, res) => {
  try {
    await fs.mkdir(paths.worldsDir, { recursive: true });
    const worldDirs = await fs.readdir(paths.worldsDir);
    const worlds = [];
    
    for (const worldDir of worldDirs) {
      try {
        const worldPath = paths.getWorldPath(worldDir);
        const stats = await fs.stat(worldPath);
        
        if (stats.isDirectory()) {
          // Try to read world.mt for display name
          let displayName = worldDir;
          try {
            const worldConfig = await fs.readFile(
              path.join(worldPath, 'world.mt'), 
              'utf8'
            );
            const nameMatch = worldConfig.match(/world_name\s*=\s*(.+)/);
            if (nameMatch) {
              displayName = nameMatch[1].trim().replace(/^["']|["']$/g, '');
            }
          } catch {}
          
          worlds.push({
            name: worldDir,
            displayName: displayName,
            path: worldPath,
            lastModified: stats.mtime
          });
        }
      } catch (error) {
        // Skip invalid world directories
      }
    }
    
    // Sort by last modified
    worlds.sort((a, b) => new Date(b.lastModified) - new Date(a.lastModified));
    
    res.json(worlds);
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

// ContentDB package info endpoint for validation
router.post('/contentdb/package-info', async (req, res) => {
  try {
    const { author, name } = req.body;
    
    if (!author || !name) {
      return res.status(400).json({ error: 'Author and name are required' });
    }
    
    const ContentDBClient = require('../utils/contentdb');
    const contentdb = new ContentDBClient();
    
    // Get package info from ContentDB
    const packageInfo = await contentdb.getPackage(author, name);
    
    res.json({
      type: packageInfo.type || 'mod',
      title: packageInfo.title || name,
      author: packageInfo.author || author,
      name: packageInfo.name || name,
      short_description: packageInfo.short_description || ''
    });
  } catch (error) {
    console.error('Error getting package info:', error);
    
    // If it's a 404 error, return that specifically
    if (error.message === 'Package not found') {
      return res.status(404).json({ error: 'Package not found on ContentDB' });
    }
    
    // For other errors, return a generic error but don't fail completely
    res.status(200).json({ 
      error: 'Could not verify package information',
      type: 'mod', // Default to mod type
      fallback: true
    });
  }
});

module.exports = {
  router,
  setSocketIO,
  serverManager,
  configManager
};