const db = require('../../database/database');
const { logger } = require('../../middleware/logger');

class DocumentTemplateRepository {
  async create(data, conn) {
    logger.info('DocumentTemplateRepository.create:start', { name: data.name, type: data.type });
    // ADDED: validate required fields + normalize optional fields
    const required = ['name', 'type', 'storageKey', 'lang'];
    for (const k of required) {
      const v = data[k];
      if (v === undefined || v === null || String(v).trim() === '') {
        const err = new Error(`Invalid document template: missing field "${k}"`);
        err.code = 'INVALID_TEMPLATE_DATA';
        logger.error('DocumentTemplateRepository.create:invalid', { field: k });
        throw err;
      }
    }
    const name = String(data.name);
    const type = String(data.type);
    const storageKey = String(data.storageKey);
    const description = data.description === undefined ? null : data.description; // avoid undefined bind
    const lang = String(data.lang);
    const allowedUserTypes = new Set(['personal', 'company', 'both']);
    const user_type = allowedUserTypes.has(data.user_type || data.userType) ? (data.user_type || data.userType) : 'both';

    const query = `
      INSERT INTO document_templates (name, type, storageKey, description, lang, user_type, version, state, createdAt, updatedAt)
      VALUES (?, ?, ?, ?, ?, ?, 1, 'inactive', NOW(), NOW())
    `;
    try {
      if (conn) {
        const [res] = await conn.execute(query, [name, type, storageKey, description, lang, user_type]);
        const insertId = res && (res.insertId || res[0]?.insertId);
        logger.info('DocumentTemplateRepository.create:success', { id: insertId || res.insertId });
        return { id: insertId || res.insertId, name, type, storageKey, description, lang, user_type, version: 1, state: 'inactive' };
      }
      const result = await db.execute(query, [name, type, storageKey, description, lang, user_type]);
      const insertId = result && result.insertId ? result.insertId : (Array.isArray(result) && result[0] && result[0].insertId ? result[0].insertId : undefined);
      logger.info('DocumentTemplateRepository.create:success', { id: insertId });
      return { id: insertId, name, type, storageKey, description, lang, user_type, version: 1, state: 'inactive' };
    } catch (error) {
      logger.error('DocumentTemplateRepository.create:error', { error: error.message });
      throw error;
    }
  }

  async findAll(conn) {
    logger.info('DocumentTemplateRepository.findAll:start');
    const query = `SELECT * FROM document_templates ORDER BY createdAt DESC`;
    try {
      if (conn) {
        const [rows] = await conn.execute(query);
        logger.info('DocumentTemplateRepository.findAll:success');
        return rows;
      }
      const result = await db.execute(query);
      // db.execute may return rows directly or [rows, fields]
      if (Array.isArray(result) && Array.isArray(result[0])) return result[0];
      logger.info('DocumentTemplateRepository.findAll:success');
      return result;
    } catch (error) {
      logger.error('DocumentTemplateRepository.findAll:error', { error: error.message });
      throw error;
    }
  }

  async findById(id, conn) {
    logger.info('DocumentTemplateRepository.findById:start', { id });
    const query = `SELECT * FROM document_templates WHERE id = ? LIMIT 1`;
    try {
      if (conn) {
        const [rows] = await conn.execute(query, [id]);
        logger.info('DocumentTemplateRepository.findById:success', { id });
        return (rows && rows[0]) ? rows[0] : null;
      }
      const result = await db.execute(query, [id]);
      if (Array.isArray(result) && Array.isArray(result[0])) {
        return result[0][0] || null;
      }
      logger.info('DocumentTemplateRepository.findById:success', { id });
      return (result && result[0]) ? result[0] : null;
    } catch (error) {
      logger.error('DocumentTemplateRepository.findById:error', { id, error: error.message });
      throw error;
    }
  }

  async update(id, data, conn) {
    logger.info('DocumentTemplateRepository.update:start', { id, data });
    // data: { name, type, storageKey, description, lang, version }
    const fields = [];
    const values = [];
    for (const key of ['name', 'type', 'storageKey', 'description', 'lang', 'version', 'user_type']) {
      if (data[key] !== undefined) {
        fields.push(`${key} = ?`);
        values.push(data[key]);
      }
    }
    // Support camelCase input
    if (data.userType !== undefined && data.user_type === undefined) {
      fields.push(`user_type = ?`);
      values.push(data.userType);
    }
    // Do not update state here
    if (!fields.length) return false;
    const query = `
      UPDATE document_templates SET ${fields.join(', ')}, updatedAt = NOW()
      WHERE id = ?
    `;
    values.push(id);
    try {
      if (conn) await conn.execute(query, values);
      else await db.execute(query, values);
      logger.info('DocumentTemplateRepository.update:success', { id });
      return true;
    } catch (error) {
      logger.error('DocumentTemplateRepository.update:error', { id, error: error.message });
      throw error;
    }
  }

  async updateState(id, state, conn) {
    logger.info('DocumentTemplateRepository.updateState:start', { id, state });
    const query = `
      UPDATE document_templates SET state = ?, updatedAt = NOW()
      WHERE id = ?
    `;
    try {
      if (conn) await conn.execute(query, [state, id]);
      else await db.execute(query, [state, id]);
      logger.info('DocumentTemplateRepository.updateState:success', { id, state });
      return true;
    } catch (error) {
      logger.error('DocumentTemplateRepository.updateState:error', { id, error: error.message });
      throw error;
    }
  }

  async delete(id, conn) {
    logger.info('DocumentTemplateRepository.delete:start', { id });
    const query = `DELETE FROM document_templates WHERE id = ?`;
    try {
      if (conn) await conn.execute(query, [id]);
      else await db.execute(query, [id]);
      logger.info('DocumentTemplateRepository.delete:success', { id });
      return true;
    } catch (error) {
      logger.error('DocumentTemplateRepository.delete:error', { id, error: error.message });
      throw error;
    }
  }

  async findActiveByUserType(userType, templateType = null, conn) {
    logger.info('DocumentTemplateRepository.findActiveByUserType:start', { userType, templateType });
    const safeType = (userType === 'personal' || userType === 'company') ? userType : 'personal';
    let query = `SELECT * FROM document_templates WHERE state = 'active' AND (user_type = ? OR user_type = 'both')`;
    const params = [safeType];
    if (templateType) {
      query += ` AND type = ?`;
      params.push(templateType);
    }
    query += ` ORDER BY createdAt DESC`;
    try {
      if (conn) {
        const [rows] = await conn.execute(query, params);
        logger.info('DocumentTemplateRepository.findActiveByUserType:success', { count: rows.length });
        return rows;
      }
      const result = await db.execute(query, params);
      const rows = Array.isArray(result) && Array.isArray(result[0]) ? result[0] : result;
      logger.info('DocumentTemplateRepository.findActiveByUserType:success', { count: rows.length });
      return rows;
    } catch (error) {
      logger.error('DocumentTemplateRepository.findActiveByUserType:error', { error: error.message });
      throw error;
    }
  }
}

module.exports = new DocumentTemplateRepository();