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.FertEnergyLog;
import com.kaidi.oa.repository.FertEnergyLogRepository;
import org.springframework.web.bind.annotation.DeleteMapping;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.PutMapping;
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.math.RoundingMode;
import java.time.Instant;
import java.time.LocalDate;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * 生物质肥料制造中心·能源消耗逐班记录 + 分摊批次 + 单位能耗对标（需求 §7，补深审计 PARTIAL[med]）。
 *
 * <ul>
 *   <li>逐班录入电/燃料/水耗，系统自动算综合能耗(kgce)与单位产品能耗(kgce/吨)，并与行业基准对标超标预警；</li>
 *   <li>GET /by-batch?batchRef= 把同一批次/工单各班能耗合计，得到该批次单位能耗（分摊到生产批次）；</li>
 *   <li>GET /benchmark 按工序汇总单耗与超标条数，干燥工序重点监控。</li>
 * </ul>
 * 综合能耗折标系数：电 1kWh≈0.1229kgce；燃料按填写的折标系数 fuelCoalFactor × fuelQty × 1000（吨标煤→kgce）。
 * 写口受 AuthInterceptor default-deny(ADMIN/APPROVER) 保护，前缀已登记入 FINANCE/SENSITIVE_READ。
 */
@RestController
@RequestMapping("/api/oa/fert-energy-logs")
public class FertEnergyLogController {

    /** 电力折标煤系数 kgce/kWh（当量值 0.1229）。 */
    private static final BigDecimal ELEC_FACTOR = new BigDecimal("0.1229");

    private final FertEnergyLogRepository repo;

    public FertEnergyLogController(FertEnergyLogRepository repo) {
        this.repo = repo;
    }

    @GetMapping
    public ApiResp<List<FertEnergyLog>> list(@RequestParam(required = false) String process,
                                             @RequestParam(required = false) Boolean overOnly) {
        if (Boolean.TRUE.equals(overOnly)) return ApiResp.ok(repo.findByOverBenchmarkTrue());
        if (process != null && !process.isBlank()) return ApiResp.ok(repo.findByProcess(process));
        return ApiResp.ok(repo.findAll());
    }

    @GetMapping("/{id}")
    public ApiResp<FertEnergyLog> get(@PathVariable Long id) {
        return ApiResp.ok(find(id));
    }

    public record EnergyRequest(String logDate, String shift, String process, String batchRef,
                                Double outputQty, Double electricityKwh, String fuelType, Double fuelQty,
                                Double fuelCoalFactor, Double waterTon, Double benchmarkKgcePerTon,
                                String recorder, String remark) {
    }

    @PostMapping
    public ApiResp<FertEnergyLog> create(@RequestBody EnergyRequest req) {
        FertEnergyLog l = new FertEnergyLog();
        l.setCreatedAt(Instant.now());
        apply(l, req);
        return ApiResp.ok(repo.save(l));
    }

    @PutMapping("/{id}")
    public ApiResp<FertEnergyLog> update(@PathVariable Long id, @RequestBody EnergyRequest req) {
        FertEnergyLog l = find(id);
        apply(l, req);
        return ApiResp.ok(repo.save(l));
    }

    @DeleteMapping("/{id}")
    public ApiResp<Void> delete(@PathVariable Long id) {
        repo.delete(find(id));
        return ApiResp.ok();
    }

    private void apply(FertEnergyLog l, EnergyRequest req) {
        l.setLogDate(req.logDate() == null || req.logDate().isBlank() ? LocalDate.now().toString() : req.logDate());
        l.setShift(req.shift() == null || req.shift().isBlank() ? "全天" : req.shift());
        l.setProcess(req.process());
        l.setBatchRef(req.batchRef());
        l.setOutputQty(bd(req.outputQty()));
        l.setElectricityKwh(bd(req.electricityKwh()));
        l.setFuelType(req.fuelType());
        l.setFuelQty(bd(req.fuelQty()));
        l.setFuelCoalFactor(bd(req.fuelCoalFactor()));
        l.setWaterTon(bd(req.waterTon()));
        l.setBenchmarkKgcePerTon(bd(req.benchmarkKgcePerTon()));
        l.setRecorder(req.recorder());
        l.setRemark(req.remark());
        recompute(l);
    }

    /** 自动计算综合能耗、单位能耗、超标判定。 */
    private void recompute(FertEnergyLog l) {
        // 电力折标：kWh × 0.1229 = kgce。
        BigDecimal elecKgce = l.getElectricityKwh().multiply(ELEC_FACTOR);
        // 燃料折标：fuelQty(吨等) × fuelCoalFactor(吨标煤/单位) × 1000(吨→千克标煤)。
        BigDecimal fuelKgce = l.getFuelQty().multiply(l.getFuelCoalFactor()).multiply(new BigDecimal("1000"));
        BigDecimal total = elecKgce.add(fuelKgce).setScale(2, RoundingMode.HALF_UP);
        l.setTotalKgce(total);
        if (l.getOutputQty().signum() > 0) {
            BigDecimal unit = total.divide(l.getOutputQty(), 2, RoundingMode.HALF_UP);
            l.setUnitKgcePerTon(unit);
            l.setOverBenchmark(l.getBenchmarkKgcePerTon().signum() > 0
                    && unit.compareTo(l.getBenchmarkKgcePerTon()) > 0);
        } else {
            l.setUnitKgcePerTon(BigDecimal.ZERO);
            l.setOverBenchmark(false);
        }
    }

    // ---------- 批次能耗分摊 ----------

    public record BatchEnergy(String batchRef, BigDecimal totalKgce, BigDecimal totalOutput,
                              BigDecimal unitKgcePerTon, BigDecimal electricityKwh, BigDecimal waterTon,
                              long logCount) {
    }

    @GetMapping("/by-batch")
    public ApiResp<BatchEnergy> byBatch(@RequestParam String batchRef) {
        if (batchRef == null || batchRef.isBlank()) {
            throw new ApiException(400, "批次/工单号(batchRef) 不能为空");
        }
        List<FertEnergyLog> logs = repo.findByBatchRef(batchRef.trim());
        BigDecimal kgce = BigDecimal.ZERO, out = BigDecimal.ZERO, elec = BigDecimal.ZERO, water = BigDecimal.ZERO;
        for (FertEnergyLog l : logs) {
            kgce = kgce.add(nz(l.getTotalKgce()));
            out = out.add(nz(l.getOutputQty()));
            elec = elec.add(nz(l.getElectricityKwh()));
            water = water.add(nz(l.getWaterTon()));
        }
        BigDecimal unit = out.signum() > 0 ? kgce.divide(out, 2, RoundingMode.HALF_UP) : BigDecimal.ZERO;
        return ApiResp.ok(new BatchEnergy(batchRef.trim(), scale(kgce), scale(out), unit, scale(elec),
                scale(water), logs.size()));
    }

    // ---------- 工序单耗对标看板 ----------

    public record ProcessBench(String process, BigDecimal totalKgce, BigDecimal totalOutput,
                               BigDecimal unitKgcePerTon, long overCount, long logCount) {
    }

    @GetMapping("/benchmark")
    public ApiResp<List<ProcessBench>> benchmark() {
        Map<String, BigDecimal[]> acc = new LinkedHashMap<>(); // [kgce, output, over, count]
        for (FertEnergyLog l : repo.findAll()) {
            String p = l.getProcess() == null || l.getProcess().isBlank() ? "未分类" : l.getProcess();
            BigDecimal[] v = acc.computeIfAbsent(p, k -> new BigDecimal[]{BigDecimal.ZERO, BigDecimal.ZERO, BigDecimal.ZERO, BigDecimal.ZERO});
            v[0] = v[0].add(nz(l.getTotalKgce()));
            v[1] = v[1].add(nz(l.getOutputQty()));
            if (Boolean.TRUE.equals(l.getOverBenchmark())) v[2] = v[2].add(BigDecimal.ONE);
            v[3] = v[3].add(BigDecimal.ONE);
        }
        List<ProcessBench> rows = new ArrayList<>();
        for (Map.Entry<String, BigDecimal[]> e : acc.entrySet()) {
            BigDecimal[] v = e.getValue();
            BigDecimal unit = v[1].signum() > 0 ? v[0].divide(v[1], 2, RoundingMode.HALF_UP) : BigDecimal.ZERO;
            rows.add(new ProcessBench(e.getKey(), scale(v[0]), scale(v[1]), unit,
                    v[2].longValue(), v[3].longValue()));
        }
        rows.sort((a, b) -> b.unitKgcePerTon().compareTo(a.unitKgcePerTon()));
        return ApiResp.ok(rows);
    }

    // ---------- helpers ----------

    private FertEnergyLog find(Long id) {
        return repo.findById(id).orElseThrow(() -> new NotFoundException("能耗记录不存在：" + id));
    }

    private static BigDecimal bd(Double v) {
        return v == null ? BigDecimal.ZERO : BigDecimal.valueOf(v).setScale(2, RoundingMode.HALF_UP);
    }

    private static BigDecimal nz(BigDecimal v) {
        return v == null ? BigDecimal.ZERO : v;
    }

    private static BigDecimal scale(BigDecimal v) {
        return nz(v).setScale(2, RoundingMode.HALF_UP);
    }
}