package com.kaidi.oa.web;

import com.kaidi.oa.common.ApiException;
import com.kaidi.oa.common.ApiResp;
import com.kaidi.oa.common.Money;
import com.kaidi.oa.common.NotFoundException;
import com.kaidi.oa.domain.AdminCleaningSchedule;
import com.kaidi.oa.domain.AdminCleaningSupply;
import com.kaidi.oa.domain.AdminCleaningSupplyMove;
import com.kaidi.oa.repository.AdminCleaningScheduleRepository;
import com.kaidi.oa.repository.AdminCleaningSupplyMoveRepository;
import com.kaidi.oa.repository.AdminCleaningSupplyRepository;
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.math.BigDecimal;
import java.time.Instant;
import java.time.LocalDate;
import java.util.ArrayList;
import java.util.List;

/**
 * 行政/办公室·保洁清洁物资专属管理（补深「保洁与绿化·清洁物资管理」PARTIAL 缺口，GAP 6, low）。
 *
 * 独立于 AdminSupplyController（通用物资），聚焦保洁域：
 *  - 清洁物资台账 CRUD（清洁剂/工具/垃圾桶等）
 *  - 入库 / 领用流水（级联维护 onHand）
 *  - 低库存预警
 *  - 由保洁排班联动触发领用（POST /{supplyId}/requisition-from-schedule?scheduleId=xxx）
 *
 * URL: /api/oa/admin-cleaning-supplies
 */
@RestController
@RequestMapping("/api/oa/admin-cleaning-supplies")
public class AdminCleaningSupplyController {

    private final AdminCleaningSupplyRepository supplyRepo;
    private final AdminCleaningSupplyMoveRepository moveRepo;
    private final AdminCleaningScheduleRepository scheduleRepo;

    public AdminCleaningSupplyController(AdminCleaningSupplyRepository supplyRepo,
                                         AdminCleaningSupplyMoveRepository moveRepo,
                                         AdminCleaningScheduleRepository scheduleRepo) {
        this.supplyRepo = supplyRepo;
        this.moveRepo = moveRepo;
        this.scheduleRepo = scheduleRepo;
    }

    // ----------------------------------------------------------------
    // 台账 CRUD
    // ----------------------------------------------------------------

    @GetMapping
    public ApiResp<List<AdminCleaningSupply>> list(
            @RequestParam(required = false) String supplyCategory,
            @RequestParam(required = false) String supplyStatus) {
        if (supplyCategory != null && !supplyCategory.isBlank()) {
            return ApiResp.ok(supplyRepo.findBySupplyCategory(supplyCategory));
        }
        if (supplyStatus != null && !supplyStatus.isBlank()) {
            return ApiResp.ok(supplyRepo.findBySupplyStatus(supplyStatus));
        }
        return ApiResp.ok(supplyRepo.findAll());
    }

    @GetMapping("/{id}")
    public ApiResp<AdminCleaningSupply> get(@PathVariable Long id) {
        return ApiResp.ok(supplyRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("清洁物资不存在: " + id)));
    }

    public record SupplyRequest(
            String supplyName, String supplyCategory, String spec,
            String unitName, Double refPrice, Double onHand,
            Double safetyStock, String location, String supplyStatus) {}

    @PostMapping
    @Transactional
    public ApiResp<AdminCleaningSupply> create(@RequestBody SupplyRequest req) {
        if (req.supplyName() == null || req.supplyName().isBlank()) {
            throw new ApiException(400, "物料名称(supplyName)不能为空");
        }
        AdminCleaningSupply s = new AdminCleaningSupply();
        long seq = supplyRepo.count() + 1;
        s.setSupplyCode("CS-" + String.format("%04d", seq));
        s.setSupplyName(req.supplyName().trim());
        s.setSupplyCategory(req.supplyCategory() == null ? "清洁剂" : req.supplyCategory());
        s.setSpec(req.spec());
        s.setUnitName(req.unitName() == null ? "个" : req.unitName());
        s.setRefPrice(req.refPrice() == null ? BigDecimal.ZERO : Money.of(req.refPrice()));
        s.setOnHand(req.onHand() == null ? 0d : req.onHand());
        s.setSafetyStock(req.safetyStock() == null ? 0d : req.safetyStock());
        s.setLocation(req.location());
        s.setSupplyStatus(req.supplyStatus() == null ? "启用" : req.supplyStatus());
        s.setCreatedAt(Instant.now());
        s.setUpdatedAt(Instant.now());
        return ApiResp.ok(supplyRepo.save(s));
    }

    @PatchMapping("/{id}")
    @Transactional
    public ApiResp<AdminCleaningSupply> update(@PathVariable Long id, @RequestBody SupplyRequest req) {
        AdminCleaningSupply s = supplyRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("清洁物资不存在: " + id));
        if (req.supplyName() != null && !req.supplyName().isBlank()) s.setSupplyName(req.supplyName().trim());
        if (req.supplyCategory() != null) s.setSupplyCategory(req.supplyCategory());
        if (req.spec() != null) s.setSpec(req.spec());
        if (req.unitName() != null) s.setUnitName(req.unitName());
        if (req.refPrice() != null) s.setRefPrice(Money.of(req.refPrice()));
        if (req.safetyStock() != null) s.setSafetyStock(req.safetyStock());
        if (req.location() != null) s.setLocation(req.location());
        if (req.supplyStatus() != null) s.setSupplyStatus(req.supplyStatus());
        s.setUpdatedAt(Instant.now());
        return ApiResp.ok(supplyRepo.save(s));
    }

    @DeleteMapping("/{id}")
    @Transactional
    public ApiResp<Void> delete(@PathVariable Long id) {
        if (!supplyRepo.existsById(id)) throw new NotFoundException("清洁物资不存在: " + id);
        supplyRepo.deleteById(id);
        return ApiResp.ok(null);
    }

    // ----------------------------------------------------------------
    // 库存流水（入库 / 领用）
    // ----------------------------------------------------------------

    @GetMapping("/{id}/moves")
    public ApiResp<List<AdminCleaningSupplyMove>> moves(@PathVariable Long id) {
        return ApiResp.ok(moveRepo.findByCleaningSupplyIdOrderByCreatedAtDesc(id));
    }

    public record MoveRequest(Double qty, String handler, String source, String moveDate, String remark) {}

    /** 入库：qty > 0，级联 onHand += qty。 */
    @PostMapping("/{id}/inbound")
    @Transactional
    public ApiResp<AdminCleaningSupplyMove> inbound(@PathVariable Long id, @RequestBody MoveRequest req) {
        AdminCleaningSupply s = supplyRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("清洁物资不存在: " + id));
        double qty = req.qty() == null ? 0 : req.qty();
        if (qty <= 0) throw new ApiException(400, "入库数量必须大于 0");
        AdminCleaningSupplyMove m = buildMove(s, "入库", qty, req, null);
        AdminCleaningSupplyMove saved = moveRepo.save(m);
        s.setOnHand(nz(s.getOnHand()) + qty);
        s.setUpdatedAt(Instant.now());
        supplyRepo.save(s);
        return ApiResp.ok(saved);
    }

    /** 领用出库：qty > 0，库存不足则拒绝，级联 onHand -= qty。 */
    @PostMapping("/{id}/requisition")
    @Transactional
    public ApiResp<AdminCleaningSupplyMove> requisition(@PathVariable Long id, @RequestBody MoveRequest req) {
        AdminCleaningSupply s = supplyRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("清洁物资不存在: " + id));
        double qty = req.qty() == null ? 0 : req.qty();
        if (qty <= 0) throw new ApiException(400, "领用数量必须大于 0");
        if (nz(s.getOnHand()) < qty) {
            throw new ApiException(409, "库存不足：当前 " + nz(s.getOnHand()) + "，申领 " + qty);
        }
        AdminCleaningSupplyMove m = buildMove(s, "领用", qty, req, null);
        AdminCleaningSupplyMove saved = moveRepo.save(m);
        s.setOnHand(nz(s.getOnHand()) - qty);
        s.setUpdatedAt(Instant.now());
        supplyRepo.save(s);
        return ApiResp.ok(saved);
    }

    /**
     * 由保洁排班联动触发领用：传入 scheduleId 自动关联排班。
     * 保洁人员完成签到后，系统自动记录本次作业对应的清洁物资领用。
     */
    @PostMapping("/{id}/requisition-from-schedule")
    @Transactional
    public ApiResp<AdminCleaningSupplyMove> requisitionFromSchedule(
            @PathVariable Long id,
            @RequestParam Long scheduleId,
            @RequestBody MoveRequest req) {
        AdminCleaningSupply s = supplyRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("清洁物资不存在: " + id));
        // 校验排班存在
        AdminCleaningSchedule sched = scheduleRepo.findById(scheduleId)
                .orElseThrow(() -> new NotFoundException("保洁排班不存在: " + scheduleId));
        double qty = req.qty() == null ? 1 : req.qty();
        if (qty <= 0) throw new ApiException(400, "领用数量必须大于 0");
        if (nz(s.getOnHand()) < qty) {
            throw new ApiException(409, "库存不足：当前 " + nz(s.getOnHand()) + "，申领 " + qty);
        }
        String handler = req.handler() == null || req.handler().isBlank() ? sched.getCleaner() : req.handler();
        String source = req.source() == null || req.source().isBlank() ? sched.getArea() : req.source();
        MoveRequest effectiveReq = new MoveRequest(qty, handler, source, req.moveDate(), req.remark());
        AdminCleaningSupplyMove m = buildMove(s, "领用", qty, effectiveReq, scheduleId);
        AdminCleaningSupplyMove saved = moveRepo.save(m);
        s.setOnHand(nz(s.getOnHand()) - qty);
        s.setUpdatedAt(Instant.now());
        supplyRepo.save(s);
        return ApiResp.ok(saved);
    }

    // ----------------------------------------------------------------
    // 低库存预警
    // ----------------------------------------------------------------

    public record LowStockAlert(Long supplyId, String supplyCode, String supplyName,
                                String supplyCategory, String unitName,
                                double onHand, double safetyStock, double shortage) {}

    /** 低库存预警：结存 < 安全库存（且安全库存 > 0），按缺口降序。 */
    @GetMapping("/alerts/low-stock")
    public ApiResp<List<LowStockAlert>> lowStockAlerts() {
        List<LowStockAlert> out = new ArrayList<>();
        for (AdminCleaningSupply s : supplyRepo.findBySupplyStatus("启用")) {
            double onHand = nz(s.getOnHand());
            double safety = nz(s.getSafetyStock());
            if (safety > 0 && onHand < safety) {
                out.add(new LowStockAlert(s.getId(), s.getSupplyCode(), s.getSupplyName(),
                        s.getSupplyCategory(), s.getUnitName(), onHand, safety, safety - onHand));
            }
        }
        out.sort((a, b) -> Double.compare(b.shortage(), a.shortage()));
        return ApiResp.ok(out);
    }

    // ----------------------------------------------------------------
    // 工具
    // ----------------------------------------------------------------

    private AdminCleaningSupplyMove buildMove(AdminCleaningSupply s, String direction,
                                              double qty, MoveRequest req, Long scheduleId) {
        AdminCleaningSupplyMove m = new AdminCleaningSupplyMove();
        m.setCleaningSupplyId(s.getId());
        m.setSupplyName(s.getSupplyName());
        m.setMoveDirection(direction);
        m.setMoveQty(qty);
        m.setHandler(req.handler());
        m.setSource(req.source());
        m.setScheduleId(scheduleId);
        m.setMoveDate(req.moveDate() == null || req.moveDate().isBlank()
                ? LocalDate.now().toString() : req.moveDate());
        m.setRemark(req.remark());
        m.setCreatedAt(Instant.now());
        return m;
    }

    private static double nz(Double v) { return v == null ? 0d : v; }
}