const Config = require('../models/Config');
const logger = require('../utils/logger');

// Get current configuration (public: userTypes, rules, sections, logo, appName)
const getConfig = async (req, res) => {
  try {
    const config = await Config.findOne().select('userTypes rules sections logo appName');
    if (!config) {
      return res.status(404).json({
        success: false,
        message: 'Konfiguration nicht gefunden'
      });
    }
    res.json({
      success: true,
      data: config
    });
  } catch (error) {
    logger.error('Fehler beim Abrufen der Konfiguration:', error);
    res.status(500).json({
      success: false,
      message: 'Fehler beim Abrufen der Konfiguration'
    });
  }
};

// Get full configuration (admin only)
const getFullConfig = async (req, res) => {
  try {
    const config = await Config.findOne().populate('updatedBy', 'username');
    if (!config) {
      return res.status(404).json({
        success: false,
        message: 'Konfiguration nicht gefunden'
      });
    }
    res.json({
      success: true,
      data: config
    });
  } catch (error) {
    logger.error('Fehler beim Abrufen der vollständigen Konfiguration:', error);
    res.status(500).json({
      success: false,
      message: 'Fehler beim Abrufen der vollständigen Konfiguration'
    });
  }
};

// Update configuration (admin only)
const updateConfig = async (req, res) => {
  try {
    const { userTypes, rules, sections, appName } = req.body;
    const adminId = req.user.id;

    // Validate userTypes
    if (!Array.isArray(userTypes) || userTypes.some(type => !type.code || !type.label)) {
      return res.status(400).json({
        success: false,
        message: 'Ungültige Benutzertypen'
      });
    }

    // Validate rules
    if (!Array.isArray(rules) || rules.some(rule => typeof rule !== 'string')) {
      return res.status(400).json({
        success: false,
        message: 'Ungültige Regeln'
      });
    }

    const updateData = { userTypes, rules, updatedBy: adminId };
    if (Array.isArray(sections)) {
      updateData.sections = sections;
    }
    if (typeof appName === 'string' && appName.trim()) {
      updateData.appName = appName.trim();
    }

    const config = await Config.findOneAndUpdate(
      {},
      updateData,
      { new: true, upsert: true, runValidators: true }
    ).populate('updatedBy', 'username');

    res.json({
      success: true,
      data: config
    });
  } catch (error) {
    logger.error('Fehler beim Aktualisieren der Konfiguration:', error);
    res.status(400).json({
      success: false,
      message: error.message || 'Fehler beim Aktualisieren der Konfiguration'
    });
  }
};

// Upload logo (admin only) - accepts base64 data URL
const uploadLogo = async (req, res) => {
  try {
    const { logo } = req.body;
    const adminId = req.user.id;

    if (!logo || typeof logo !== 'string') {
      return res.status(400).json({ success: false, message: 'Kein Logo-Bild übermittelt' });
    }

    // Only allow safe image data URLs (block SVG to prevent stored XSS)
    const ALLOWED_LOGO_TYPES = [
      'data:image/jpeg;base64,',
      'data:image/png;base64,',
      'data:image/webp;base64,'
    ];
    if (!ALLOWED_LOGO_TYPES.some(t => logo.startsWith(t))) {
      return res.status(400).json({ success: false, message: 'Ungültiges Bildformat. Erlaubt: JPEG, PNG, WebP' });
    }

    const config = await Config.findOneAndUpdate(
      {},
      { logo, updatedBy: adminId },
      { new: true, upsert: true }
    );

    res.json({ success: true, data: { logo: config.logo } });
  } catch (error) {
    logger.error('Fehler beim Logo-Upload:', error);
    res.status(500).json({ success: false, message: 'Fehler beim Logo-Upload' });
  }
};

// Delete logo (admin only)
const deleteLogo = async (req, res) => {
  try {
    const adminId = req.user.id;
    await Config.findOneAndUpdate({}, { logo: null, updatedBy: adminId });
    res.json({ success: true });
  } catch (error) {
    logger.error('Fehler beim Löschen des Logos:', error);
    res.status(500).json({ success: false, message: 'Fehler beim Löschen des Logos' });
  }
};

module.exports = {
  getConfig,
  getFullConfig,
  updateConfig,
  uploadLogo,
  deleteLogo
};