/**
 * 业务台账服务
 * 为合作伙伴提供统一的业务台账数据
 */
const db = require('../db');

class LedgerService {
  static async getSubcontractorLedger(subcontractorId) {
    try {
      const projectsResult = await db.query(`
        SELECT p.id, p.code as project_code, p.name, p.contract_amount, p.status
        FROM projects p
        WHERE p.subcontractor_id = ?
        ORDER BY p.created_at DESC
      `, [subcontractorId]);

      const projects = projectsResult.rows;
      const totalContract = projects.reduce((sum, p) => sum + (parseFloat(p.contract_amount) || 0), 0);

      let totalPaid = 0;
      try {
        const paymentsResult = await db.query(`
          SELECT COALESCE(SUM(amount), 0) as paid_amount
          FROM payment_requests
          WHERE payee_type = 'subcontractor' AND payee_id = ? AND status = 'paid'
        `, [subcontractorId]);
        totalPaid = parseFloat(paymentsResult.rows[0]?.paid_amount) || 0;
      } catch (e) { /* payment_requests may not have payee_type column */ }

      return {
        summary: {
          item_count: projects.length,
          total_contract_amount: totalContract,
          total_paid_amount: totalPaid,
          total_unpaid_amount: totalContract - totalPaid
        },
        items: projects.map(p => ({
          id: p.id, type: 'project', code: p.project_code, name: p.name,
          contract_amount: parseFloat(p.contract_amount) || 0,
          paid_amount: 0, unpaid_amount: parseFloat(p.contract_amount) || 0,
          status: p.status
        }))
      };
    } catch (error) {
      console.error('获取分包商台账失败:', error);
      return { summary: { item_count: 0, total_contract_amount: 0, total_paid_amount: 0, total_unpaid_amount: 0 }, items: [] };
    }
  }

  static async getCustomerLedger(customerId) {
    try {
      const projectsResult = await db.query(`
        SELECT p.id, p.code as project_code, p.name, p.contract_amount, p.status
        FROM projects p
        WHERE p.customer_id = ?
        ORDER BY p.created_at DESC
      `, [customerId]);

      const projects = projectsResult.rows;
      const totalContract = projects.reduce((sum, p) => sum + (parseFloat(p.contract_amount) || 0), 0);

      let totalReceived = 0;
      try {
        const receiptsResult = await db.query(`
          SELECT COALESCE(SUM(amount), 0) as received_amount
          FROM payment_records
          WHERE customer_id = ? AND type = 'income'
        `, [customerId]);
        totalReceived = parseFloat(receiptsResult.rows[0]?.received_amount) || 0;
      } catch (e) { /* ignore */ }

      return {
        summary: {
          item_count: projects.length,
          total_contract_amount: totalContract,
          total_received_amount: totalReceived,
          total_receivable_amount: totalContract - totalReceived
        },
        items: projects.map(p => ({
          id: p.id, type: 'project', code: p.project_code, name: p.name,
          contract_amount: parseFloat(p.contract_amount) || 0,
          received_amount: 0, receivable_amount: parseFloat(p.contract_amount) || 0,
          status: p.status
        }))
      };
    } catch (error) {
      console.error('获取客户台账失败:', error);
      return { summary: { item_count: 0, total_contract_amount: 0, total_received_amount: 0, total_receivable_amount: 0 }, items: [] };
    }
  }

  static async getSupplierLedger(supplierId) {
    try {
      const ordersResult = await db.query(`
        SELECT po.id, po.code, po.total_amount, po.status, po.created_at,
               p.name as project_name
        FROM purchase_orders po
        LEFT JOIN projects p ON po.project_id = p.id
        WHERE po.supplier_id = ?
        ORDER BY po.created_at DESC
      `, [supplierId]);

      const orders = ordersResult.rows;
      const totalAmount = orders.reduce((sum, o) => sum + (parseFloat(o.total_amount) || 0), 0);

      let totalPaid = 0;
      try {
        const paymentsResult = await db.query(`
          SELECT COALESCE(SUM(pp.actual_amount), 0) as paid_amount
          FROM payment_plans pp
          JOIN purchase_orders po ON pp.purchase_order_id = po.id
          WHERE po.supplier_id = ? AND pp.status = 'paid'
        `, [supplierId]);
        totalPaid = parseFloat(paymentsResult.rows[0]?.paid_amount) || 0;
      } catch (e) { /* ignore */ }

      return {
        summary: {
          item_count: orders.length,
          total_order_amount: totalAmount,
          total_paid_amount: totalPaid,
          total_unpaid_amount: totalAmount - totalPaid
        },
        items: orders.map(o => ({
          id: o.id, type: 'purchase_order', code: o.code, name: o.project_name || o.code,
          order_amount: parseFloat(o.total_amount) || 0,
          paid_amount: 0, unpaid_amount: parseFloat(o.total_amount) || 0,
          status: o.status, date: o.created_at
        }))
      };
    } catch (error) {
      console.error('获取供应商台账失败:', error);
      return { summary: { item_count: 0, total_order_amount: 0, total_paid_amount: 0, total_unpaid_amount: 0 }, items: [] };
    }
  }

  static async getLogisticsCompanyLedger(companyId) {
    try {
      const ordersResult = await db.query(`
        SELECT lr.id, lr.code, lr.ship_date, lr.status,
               lr.primary_freight, lr.primary_freight_currency, lr.primary_freight_status,
               lr.secondary_freight, lr.secondary_freight_currency, lr.secondary_freight_status,
               po.code as order_code, p.name as project_name
        FROM logistics_records lr
        LEFT JOIN purchase_orders po ON lr.purchase_order_id = po.id
        LEFT JOIN projects p ON po.project_id = p.id
        WHERE lr.logistics_company_id = ?
        ORDER BY lr.created_at DESC
      `, [companyId]);

      const orders = ordersResult.rows;
      const totalPrimary = orders.reduce((sum, o) => sum + (parseFloat(o.primary_freight) || 0), 0);
      const totalSecondary = orders.reduce((sum, o) => sum + (parseFloat(o.secondary_freight) || 0), 0);
      const paidPrimary = orders.filter(o => o.primary_freight_status === 'paid').reduce((sum, o) => sum + (parseFloat(o.primary_freight) || 0), 0);
      const paidSecondary = orders.filter(o => o.secondary_freight_status === 'paid').reduce((sum, o) => sum + (parseFloat(o.secondary_freight) || 0), 0);

      return {
        summary: {
          item_count: orders.length,
          total_primary_freight: totalPrimary,
          total_secondary_freight: totalSecondary,
          total_freight: totalPrimary + totalSecondary,
          paid_primary_freight: paidPrimary,
          paid_secondary_freight: paidSecondary,
          paid_amount: paidPrimary + paidSecondary,
          unpaid_amount: (totalPrimary + totalSecondary) - (paidPrimary + paidSecondary)
        },
        items: orders.map(o => ({
          id: o.id, type: 'logistics_record', code: o.code, name: o.order_code || o.code,
          project_name: o.project_name,
          primary_freight: parseFloat(o.primary_freight) || 0,
          primary_freight_currency: o.primary_freight_currency || 'CNY',
          primary_freight_status: o.primary_freight_status,
          secondary_freight: parseFloat(o.secondary_freight) || 0,
          secondary_freight_currency: o.secondary_freight_currency || 'LAK',
          secondary_freight_status: o.secondary_freight_status,
          status: o.status, date: o.ship_date
        }))
      };
    } catch (error) {
      console.error('获取物流公司台账失败:', error);
      return { summary: { item_count: 0, total_primary_freight: 0, total_secondary_freight: 0, total_freight: 0, paid_primary_freight: 0, paid_secondary_freight: 0, paid_amount: 0, unpaid_amount: 0 }, items: [] };
    }
  }
}

module.exports = LedgerService;