const express = require('express');
const { paginate, parsePaginationParams } = require('../pagination');
const { ValidationError } = require('../errors');

/**
 * Updates route factory
 * @param {Object} deps - Explicit dependencies
 * @param {Object} deps.updateManager - Container update manager
 * @param {Object} deps.selfUpdater - DashCaddy self-update manager
 * @param {Function} deps.asyncHandler - Async route handler wrapper
 * @param {Function} deps.logError - Error logging function
 * @returns {express.Router}
 */
module.exports = function({ updateManager, selfUpdater, asyncHandler, logError }) {
  const router = express.Router();

  // ===== UPDATE MANAGEMENT ENDPOINTS =====

  // Check for updates
  router.post('/updates/check', asyncHandler(async (req, res) => {
    await updateManager.checkForUpdates();
    const updates = updateManager.getAvailableUpdates();
    res.json({ success: true, updates, count: updates.length });
  }, 'updates-check'));

  // Get available updates
  router.get('/updates/available', asyncHandler(async (req, res) => {
    const updates = updateManager.getAvailableUpdates();
    const paginationParams = parsePaginationParams(req.query);
    const result = paginate(updates, paginationParams);
    res.json({ success: true, updates: result.data, count: updates.length, ...(result.pagination && { pagination: result.pagination }) });
  }, 'updates-available'));

  // Update a container
  router.post('/updates/update/:containerId', asyncHandler(async (req, res) => {
    const result = await updateManager.updateContainer(req.params.containerId, req.body);
    res.json({ success: true, result });
  }, 'updates-update'));

  // Rollback update
  router.post('/updates/rollback/:containerId', asyncHandler(async (req, res) => {
    await updateManager.rollbackUpdate(req.params.containerId);
    res.json({ success: true, message: 'Rollback completed' });
  }, 'updates-rollback'));

  // Get update history
  router.get('/updates/history', asyncHandler(async (req, res) => {
    const paginationParams = parsePaginationParams(req.query);
    // When paginating, fetch all history so pagination can slice correctly
    const fetchLimit = paginationParams ? Number.MAX_SAFE_INTEGER : (parseInt(req.query.limit) || 50);
    const history = updateManager.getHistory(fetchLimit);
    const result = paginate(history, paginationParams);
    res.json({ success: true, history: result.data, ...(result.pagination && { pagination: result.pagination }) });
  }, 'updates-history'));

  // Configure auto-update
  router.post('/updates/auto-update/:containerId', asyncHandler(async (req, res) => {
    updateManager.configureAutoUpdate(req.params.containerId, req.body);
    res.json({ success: true, message: 'Auto-update configured' });
  }, 'updates-auto-update'));

  // Get auto-update configuration
  router.get('/updates/auto-update', asyncHandler(async (req, res) => {
    const config = updateManager.getAutoUpdateConfig();
    res.json({ success: true, config });
  }, 'updates-auto-update-config'));

  // Schedule update
  router.post('/updates/schedule/:containerId', asyncHandler(async (req, res) => {
    const { scheduledTime } = req.body;
    if (!scheduledTime) {
      throw new ValidationError('scheduledTime is required');
    }
    updateManager.scheduleUpdate(req.params.containerId, scheduledTime);
    res.json({ success: true, message: 'Update scheduled', scheduledTime });
  }, 'updates-schedule'));

  // ===== DASHCADDY SELF-UPDATE ENDPOINTS =====

  // Get current version
  router.get('/system/version', asyncHandler(async (req, res) => {
    const local = selfUpdater.getLocalVersion();
    res.json({ success: true, name: 'DashCaddy', version: local.version, commit: local.commit });
  }, 'system-version'));

  // Check for DashCaddy update
  router.get('/system/update-check', asyncHandler(async (req, res) => {
    const result = await selfUpdater.checkForUpdate();
    res.json({ success: true, ...result });
  }, 'system-update-check'));

  // Apply available update
  router.post('/system/update-apply', asyncHandler(async (req, res) => {
    const check = await selfUpdater.checkForUpdate();
    if (!check.available) {
      return res.json({ success: true, message: 'Already up to date' });
    }
    // Start async — container may restart
    selfUpdater.applyUpdate(check.remote).catch(err => {
      logError('self-update', err);
    });
    res.json({
      success: true,
      message: 'Update initiated',
      fromVersion: check.local.version,
      toVersion: check.remote.version,
    });
  }, 'system-update-apply'));

  // Get update status
  router.get('/system/update-status', asyncHandler(async (req, res) => {
    res.json({
      success: true,
      status: selfUpdater.getStatus(),
      lastCheck: selfUpdater.lastCheckTime,
      lastResult: selfUpdater.lastCheckResult,
    });
  }, 'system-update-status'));

  // Get self-update history
  router.get('/system/update-history', asyncHandler(async (req, res) => {
    const history = selfUpdater.getUpdateHistory();
    res.json({ success: true, history });
  }, 'system-update-history'));

  // List rollback versions
  router.get('/system/rollback-versions', asyncHandler(async (req, res) => {
    const versions = selfUpdater.getAvailableRollbacks();
    res.json({ success: true, versions });
  }, 'system-rollback-versions'));

  // Rollback to a previous version
  router.post('/system/rollback', asyncHandler(async (req, res) => {
    const { version } = req.body;
    if (!version) throw new ValidationError('version is required');
    selfUpdater.rollbackToVersion(version).catch(err => {
      logError('self-rollback', err);
    });
    res.json({ success: true, message: `Rollback to ${version} initiated` });
  }, 'system-rollback'));

  return router;
};
