package com.kaidi.oa.web;

import com.kaidi.oa.common.ApiException;
import com.kaidi.oa.common.ApiResp;
import com.kaidi.oa.common.NotFoundException;
import com.kaidi.oa.domain.AdminShuttleBus;
import com.kaidi.oa.domain.AdminShuttlePassenger;
import com.kaidi.oa.repository.AdminShuttleBusRepository;
import com.kaidi.oa.repository.AdminShuttlePassengerRepository;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PatchMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.time.Instant;
import java.time.LocalDate;
import java.util.List;
import java.util.Map;

/**
 * 行政/办公室·通勤班车管理。
 *
 * 功能：班车路线台账（起终点/途经站/发车时间/返程时间/关联车辆/司机/运行日/座位数） +
 * 乘客预约（员工每日预约乘坐/取消 + 乘客统计/满座预警） +
 * 路线状态管理（运营中/暂停/停运）。
 *
 * 预约逻辑：同一乘客同日同方向只能预约一次（重复预约抛 409）；预约后自动更新班车 bookedCount。
 */
@RestController
@RequestMapping("/api/oa/admin-shuttle-buses")
public class AdminShuttleBusController {

    private final AdminShuttleBusRepository busRepo;
    private final AdminShuttlePassengerRepository passengerRepo;

    public AdminShuttleBusController(AdminShuttleBusRepository busRepo,
                                     AdminShuttlePassengerRepository passengerRepo) {
        this.busRepo = busRepo;
        this.passengerRepo = passengerRepo;
    }

    // ==================== 班车路线 ====================

    @GetMapping
    public ApiResp<List<AdminShuttleBus>> listBuses(
            @RequestParam(required = false) String status) {
        if (status != null && !status.isBlank()) {
            return ApiResp.ok(busRepo.findByStatus(status));
        }
        return ApiResp.ok(busRepo.findAllByOrderByRouteNameAsc());
    }

    @GetMapping("/{id}")
    public ApiResp<AdminShuttleBus> getBus(@PathVariable Long id) {
        return ApiResp.ok(busRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("班车路线不存在: " + id)));
    }

    public record BusRequest(
            String routeName, String startStop, String endStop,
            String stops, String departureTime, String returnTime,
            String vehiclePlate, String driver, Integer seats,
            String runDays, String status, String remark) {
    }

    @PostMapping
    @Transactional
    public ApiResp<AdminShuttleBus> createBus(@RequestBody BusRequest req) {
        if (req.routeName() == null || req.routeName().isBlank()) {
            throw new ApiException(400, "路线名称(routeName) 不能为空");
        }
        AdminShuttleBus bus = new AdminShuttleBus();
        bus.setRouteName(req.routeName());
        bus.setStartStop(req.startStop());
        bus.setEndStop(req.endStop());
        bus.setStops(req.stops());
        bus.setDepartureTime(req.departureTime());
        bus.setReturnTime(req.returnTime());
        bus.setVehiclePlate(req.vehiclePlate());
        bus.setDriver(req.driver());
        bus.setSeats(req.seats() == null ? 45 : req.seats());
        bus.setBookedCount(0);
        bus.setRunDays(req.runDays() == null ? "工作日" : req.runDays());
        bus.setStatus(req.status() == null ? "运营中" : req.status());
        bus.setRemark(req.remark());
        bus.setCreatedAt(Instant.now());
        bus.setUpdatedAt(Instant.now());
        return ApiResp.ok(busRepo.save(bus));
    }

    @PatchMapping("/{id}")
    @Transactional
    public ApiResp<AdminShuttleBus> updateBus(@PathVariable Long id, @RequestBody BusRequest req) {
        AdminShuttleBus bus = busRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("班车路线不存在: " + id));
        if (req.routeName() != null && !req.routeName().isBlank()) bus.setRouteName(req.routeName());
        if (req.startStop() != null) bus.setStartStop(req.startStop());
        if (req.endStop() != null) bus.setEndStop(req.endStop());
        if (req.stops() != null) bus.setStops(req.stops());
        if (req.departureTime() != null) bus.setDepartureTime(req.departureTime());
        if (req.returnTime() != null) bus.setReturnTime(req.returnTime());
        if (req.vehiclePlate() != null) bus.setVehiclePlate(req.vehiclePlate());
        if (req.driver() != null) bus.setDriver(req.driver());
        if (req.seats() != null) bus.setSeats(req.seats());
        if (req.runDays() != null) bus.setRunDays(req.runDays());
        if (req.status() != null) bus.setStatus(req.status());
        if (req.remark() != null) bus.setRemark(req.remark());
        bus.setUpdatedAt(Instant.now());
        return ApiResp.ok(busRepo.save(bus));
    }

    /** 暂停班车路线 */
    @PostMapping("/{id}/suspend")
    @Transactional
    public ApiResp<AdminShuttleBus> suspend(@PathVariable Long id) {
        AdminShuttleBus bus = busRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("班车路线不存在: " + id));
        if (!"运营中".equals(bus.getStatus())) {
            throw new ApiException(409, "只有「运营中」状态可暂停");
        }
        bus.setStatus("暂停");
        bus.setUpdatedAt(Instant.now());
        return ApiResp.ok(busRepo.save(bus));
    }

    /** 恢复运营 */
    @PostMapping("/{id}/resume")
    @Transactional
    public ApiResp<AdminShuttleBus> resume(@PathVariable Long id) {
        AdminShuttleBus bus = busRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("班车路线不存在: " + id));
        bus.setStatus("运营中");
        bus.setUpdatedAt(Instant.now());
        return ApiResp.ok(busRepo.save(bus));
    }

    @DeleteMapping("/{id}")
    @Transactional
    public ApiResp<Void> deleteBus(@PathVariable Long id) {
        AdminShuttleBus bus = busRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("班车路线不存在: " + id));
        busRepo.delete(bus);
        return ApiResp.ok(null);
    }

    // ==================== 乘客预约 ====================

    @GetMapping("/{id}/passengers")
    public ApiResp<List<AdminShuttlePassenger>> listPassengers(
            @PathVariable Long id,
            @RequestParam(required = false) String rideDate) {
        if (rideDate != null && !rideDate.isBlank()) {
            return ApiResp.ok(passengerRepo.findByShuttleIdAndRideDate(id, rideDate));
        }
        return ApiResp.ok(passengerRepo.findByStatus("已预约").stream()
                .filter(p -> id.equals(p.getShuttleId())).toList());
    }

    public record BookRequest(String passenger, String dept, String rideDate,
                              String direction, String boardStop) {
    }

    /** 预约乘坐：员工在线预约班车，满座时抛 409 */
    @PostMapping("/{id}/book")
    @Transactional
    public ApiResp<AdminShuttlePassenger> book(@PathVariable Long id, @RequestBody BookRequest req) {
        AdminShuttleBus bus = busRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("班车路线不存在: " + id));
        if (!"运营中".equals(bus.getStatus())) {
            throw new ApiException(409, "班车路线当前状态为「" + bus.getStatus() + "」，无法预约");
        }
        if (req.passenger() == null || req.passenger().isBlank()) {
            throw new ApiException(400, "乘客姓名(passenger) 不能为空");
        }
        String rideDate = req.rideDate() == null ? LocalDate.now().toString() : req.rideDate();
        String direction = req.direction() == null ? "去" : req.direction();

        // 重复预约校验
        List<AdminShuttlePassenger> existing = passengerRepo.findByShuttleIdAndRideDate(id, rideDate);
        boolean alreadyBooked = existing.stream()
                .anyMatch(p -> req.passenger().equals(p.getPassenger())
                        && direction.equals(p.getDirection())
                        && !"已取消".equals(p.getStatus()));
        if (alreadyBooked) {
            throw new ApiException(409, "该乘客(" + req.passenger() + ")当日已预约此方向班车");
        }

        // 满座检验
        int booked = (int) existing.stream()
                .filter(p -> direction.equals(p.getDirection()) && !"已取消".equals(p.getStatus()))
                .count();
        int seats = bus.getSeats() == null ? 45 : bus.getSeats();
        if (booked >= seats) {
            throw new ApiException(409, "班车座位已满（" + seats + "座）");
        }

        AdminShuttlePassenger sp = new AdminShuttlePassenger();
        sp.setShuttleId(id);
        sp.setPassenger(req.passenger());
        sp.setDept(req.dept());
        sp.setRideDate(rideDate);
        sp.setDirection(direction);
        sp.setBoardStop(req.boardStop());
        sp.setStatus("已预约");
        sp.setCreatedAt(Instant.now());
        AdminShuttlePassenger saved = passengerRepo.save(sp);

        // 更新班车预约计数
        bus.setBookedCount(booked + 1);
        bus.setUpdatedAt(Instant.now());
        busRepo.save(bus);

        return ApiResp.ok(saved);
    }

    /** 取消预约 */
    @PostMapping("/passengers/{pid}/cancel")
    @Transactional
    public ApiResp<AdminShuttlePassenger> cancelBooking(@PathVariable Long pid) {
        AdminShuttlePassenger p = passengerRepo.findById(pid)
                .orElseThrow(() -> new NotFoundException("预约记录不存在: " + pid));
        if ("已取消".equals(p.getStatus())) {
            throw new ApiException(409, "预约已取消");
        }
        p.setStatus("已取消");
        // 更新班车预约计数
        busRepo.findById(p.getShuttleId()).ifPresent(bus -> {
            int cur = bus.getBookedCount() == null ? 0 : bus.getBookedCount();
            bus.setBookedCount(Math.max(0, cur - 1));
            bus.setUpdatedAt(Instant.now());
            busRepo.save(bus);
        });
        return ApiResp.ok(passengerRepo.save(p));
    }

    /** 乘客统计：某日各路线预约数 / 到达数 */
    @GetMapping("/stats")
    public ApiResp<Map<String, Object>> stats(@RequestParam(required = false) String date) {
        String d = date == null ? LocalDate.now().toString() : date;
        List<AdminShuttleBus> buses = busRepo.findAllByOrderByRouteNameAsc();
        List<Map<String, Object>> rows = new java.util.ArrayList<>();
        int totalBooked = 0;
        int totalRode = 0;
        for (AdminShuttleBus bus : buses) {
            List<AdminShuttlePassenger> dayPassengers = passengerRepo.findByShuttleIdAndRideDate(bus.getId(), d);
            int booked = (int) dayPassengers.stream().filter(p -> !"已取消".equals(p.getStatus())).count();
            int rode = (int) dayPassengers.stream().filter(p -> "已乘坐".equals(p.getStatus())).count();
            totalBooked += booked;
            totalRode += rode;
            rows.add(Map.of(
                    "busId", bus.getId(),
                    "routeName", bus.getRouteName(),
                    "status", bus.getStatus() == null ? "" : bus.getStatus(),
                    "seats", bus.getSeats() == null ? 0 : bus.getSeats(),
                    "bookedToday", booked,
                    "rodToday", rode,
                    "loadRate", bus.getSeats() == null || bus.getSeats() == 0 ? 0.0
                            : Math.round((double) booked / bus.getSeats() * 100.0) / 100.0));
        }
        return ApiResp.ok(Map.of("date", d, "totalBooked", totalBooked,
                "totalRode", totalRode, "routes", rows));
    }
}