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.Budget;
import com.kaidi.oa.domain.SafetyInvestment;
import com.kaidi.oa.repository.BudgetRepository;
import com.kaidi.oa.repository.SafetyInvestmentRepository;
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.math.RoundingMode;
import java.time.Instant;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * 质安部·安全投入管理（需求 §2 安全投入管理）。补深审计 high 缺口：安全生产费用按类别/项目归集 +
 * 计划/使用金额统计（与财务联动基础）。金额一律 BigDecimal，经 Money 收口。
 *
 * 写口默认受 AuthInterceptor default-deny(ADMIN/APPROVER) 保护；含金额，已登记进 SENSITIVE_READ_PREFIXES。
 */
@RestController
@RequestMapping("/api/oa/safety-investments")
public class SafetyInvestmentController {

    private final SafetyInvestmentRepository repo;
    private final BudgetRepository budgetRepo;

    public SafetyInvestmentController(SafetyInvestmentRepository repo, BudgetRepository budgetRepo) {
        this.repo = repo;
        this.budgetRepo = budgetRepo;
    }

    @GetMapping
    public ApiResp<List<SafetyInvestment>> list(@RequestParam(required = false) String category,
                                                @RequestParam(required = false) String period,
                                                @RequestParam(required = false) Long projectId) {
        if (category != null && !category.isBlank()) {
            return ApiResp.ok(repo.findByCategory(category));
        }
        if (period != null && !period.isBlank()) {
            return ApiResp.ok(repo.findByPeriod(period));
        }
        if (projectId != null) {
            return ApiResp.ok(repo.findByProjectId(projectId));
        }
        return ApiResp.ok(repo.findAll());
    }

    @GetMapping("/{id}")
    public ApiResp<SafetyInvestment> get(@PathVariable Long id) {
        return ApiResp.ok(repo.findById(id)
                .orElseThrow(() -> new NotFoundException("investment not found: " + id)));
    }

    public record InvestRequest(String code, String category, String item, Long projectId, String dept,
                                Double amount, Double usedAmount, String occurDate, String period,
                                String operator) {
    }

    @PostMapping
    public ApiResp<SafetyInvestment> create(@RequestBody InvestRequest req) {
        if (req.category() == null || req.category().isBlank()) {
            throw new ApiException(400, "费用类别不能为空");
        }
        SafetyInvestment s = new SafetyInvestment();
        s.setCode(req.code() == null || req.code().isBlank() ? "AQTR-" + (repo.count() + 1) : req.code());
        s.setCategory(req.category());
        s.setItem(req.item());
        s.setProjectId(req.projectId());
        s.setDept(req.dept());
        s.setAmount(Money.of(req.amount()));
        s.setUsedAmount(Money.of(req.usedAmount()));
        s.setOccurDate(req.occurDate());
        s.setPeriod(req.period());
        s.setOperator(req.operator());
        s.setStatus(Money.gt(s.getUsedAmount(), Money.ZERO) ? "已使用" : "登记");
        s.setCreatedAt(Instant.now());
        return ApiResp.ok(repo.save(s));
    }

    @PatchMapping("/{id}")
    public ApiResp<SafetyInvestment> update(@PathVariable Long id, @RequestBody InvestRequest req) {
        SafetyInvestment s = repo.findById(id)
                .orElseThrow(() -> new NotFoundException("investment not found: " + id));
        if (req.category() != null && !req.category().isBlank()) s.setCategory(req.category());
        if (req.item() != null) s.setItem(req.item());
        if (req.projectId() != null) s.setProjectId(req.projectId());
        if (req.dept() != null) s.setDept(req.dept());
        if (req.amount() != null) s.setAmount(Money.of(req.amount()));
        if (req.usedAmount() != null) s.setUsedAmount(Money.of(req.usedAmount()));
        if (req.occurDate() != null) s.setOccurDate(req.occurDate());
        if (req.period() != null) s.setPeriod(req.period());
        if (req.operator() != null) s.setOperator(req.operator());
        s.setStatus(Money.gt(s.getUsedAmount(), Money.ZERO) ? "已使用" : "登记");
        return ApiResp.ok(repo.save(s));
    }

    @DeleteMapping("/{id}")
    public ApiResp<Void> delete(@PathVariable Long id) {
        if (!repo.existsById(id)) {
            throw new NotFoundException("investment not found: " + id);
        }
        repo.deleteById(id);
        return ApiResp.ok(null);
    }

    // ---------- 归集统计（按类别 / 项目） ----------

    public record CatRow(String category, long count, BigDecimal planned, BigDecimal used, double useRate) {
    }

    public record InvestSummary(BigDecimal totalPlanned, BigDecimal totalUsed, double overallUseRate,
                                List<CatRow> byCategory) {
    }

    /** 安全投入汇总：按类别归集计划/使用金额 + 使用率，可按 period 过滤。 */
    @GetMapping("/summary")
    public ApiResp<InvestSummary> summary(@RequestParam(required = false) String period) {
        List<SafetyInvestment> all = (period == null || period.isBlank())
                ? repo.findAll() : repo.findByPeriod(period);
        Map<String, BigDecimal[]> byCat = new LinkedHashMap<>();
        Map<String, Long> cnt = new LinkedHashMap<>();
        BigDecimal totalPlan = Money.ZERO, totalUsed = Money.ZERO;
        for (SafetyInvestment s : all) {
            String cat = s.getCategory() == null || s.getCategory().isBlank() ? "其他" : s.getCategory();
            BigDecimal[] a = byCat.computeIfAbsent(cat, k -> new BigDecimal[]{Money.ZERO, Money.ZERO});
            a[0] = Money.add(a[0], s.getAmount());
            a[1] = Money.add(a[1], s.getUsedAmount());
            cnt.merge(cat, 1L, Long::sum);
            totalPlan = Money.add(totalPlan, s.getAmount());
            totalUsed = Money.add(totalUsed, s.getUsedAmount());
        }
        List<CatRow> rows = new ArrayList<>();
        for (Map.Entry<String, BigDecimal[]> e : byCat.entrySet()) {
            BigDecimal[] a = e.getValue();
            rows.add(new CatRow(e.getKey(), cnt.getOrDefault(e.getKey(), 0L), a[0], a[1], useRate(a[0], a[1])));
        }
        return ApiResp.ok(new InvestSummary(totalPlan, totalUsed, useRate(totalPlan, totalUsed), rows));
    }

    private static double useRate(BigDecimal planned, BigDecimal used) {
        if (Money.lte0(planned)) {
            return 0.0;
        }
        return Math.round(Money.nz(used).doubleValue() / Money.nz(planned).doubleValue() * 1000.0) / 10.0;
    }

    // ---------- 安全投入与财务联动校验（需求 §2 安全投入管理——与财务联动校验） ----------

    /**
     * 法规提取率核查项（每个 period + category 的计划额 vs. 实际可用预算）。
     * compliant=true 表示安全费用提取/使用比例符合法规要求（提取率>=2%营业收入，使用率>=80%）。
     */
    public record FinanceCheckRow(
            String period, String category,
            BigDecimal invested, BigDecimal budgetActual,
            double extractRate, double useRate,
            boolean compliant, String note) {
    }

    public record FinanceCheckResult(
            String checkDate, String period,
            BigDecimal totalInvested, BigDecimal totalBudget,
            double overallUseRate, boolean overallCompliant,
            List<FinanceCheckRow> details, List<String> violations) {
    }

    /**
     * 安全投入与财务联动校验端点（补完 Gap 2 缺口）。
     * 逻辑：
     * 1. 汇总本期（period）所有安全投入计划额与实际使用额；
     * 2. 关联财务预算中 element=安全费 / 管理费 的预算条目，获取 budgetAmount（提取上限基准）；
     * 3. 按类别校验使用率（已使用/计划≥80% 视为合规），并核查总提取额是否超出预算；
     * 4. 汇总违规项，返回可供财务审核的合规报告。
     *
     * 此端点不改写任何数据，纯读侧聚合。
     */
    @GetMapping("/finance-check")
    public ApiResp<FinanceCheckResult> financeCheck(@RequestParam(required = false) String period) {
        String checkPeriod = (period == null || period.isBlank())
                ? String.valueOf(java.time.LocalDate.now().getYear()) : period;

        // 1. 汇总安全投入
        List<SafetyInvestment> investments = repo.findByPeriod(checkPeriod);
        if (investments.isEmpty()) {
            // 没有按 period 精确匹配时退回所有
            investments = repo.findAll();
        }

        Map<String, BigDecimal[]> byCat = new LinkedHashMap<>();
        BigDecimal totalInvested = Money.ZERO, totalUsed = Money.ZERO;
        for (SafetyInvestment s : investments) {
            String cat = s.getCategory() == null || s.getCategory().isBlank() ? "其他" : s.getCategory();
            BigDecimal[] a = byCat.computeIfAbsent(cat, k -> new BigDecimal[]{Money.ZERO, Money.ZERO});
            a[0] = Money.add(a[0], s.getAmount());    // 计划额
            a[1] = Money.add(a[1], s.getUsedAmount()); // 使用额
            totalInvested = Money.add(totalInvested, s.getAmount());
            totalUsed = Money.add(totalUsed, s.getUsedAmount());
        }

        // 2. 从预算台账中取 element=安全费 / 管理费 条目（按 period 匹配）
        List<Budget> budgets = budgetRepo.findAll();
        BigDecimal totalBudget = Money.ZERO;
        for (Budget b : budgets) {
            String elem = b.getElement();
            String bPeriod = b.getPeriod() == null ? "" : b.getPeriod();
            boolean periodMatch = bPeriod.isBlank() || bPeriod.equals(checkPeriod)
                    || bPeriod.startsWith(checkPeriod);
            boolean elemMatch = "安全费".equals(elem) || "管理费".equals(elem)
                    || "培训费".equals(elem) || "保险费".equals(elem);
            if (elemMatch && periodMatch && b.getBudgetAmount() != null) {
                totalBudget = Money.add(totalBudget, b.getBudgetAmount());
            }
        }

        // 3. 逐类别校验
        List<FinanceCheckRow> details = new ArrayList<>();
        List<String> violations = new ArrayList<>();

        // 法规阈值：使用率 >= 80% 合规（《安全生产费用提取和使用管理办法》）
        BigDecimal USE_RATE_THRESHOLD = new BigDecimal("80.0");

        for (Map.Entry<String, BigDecimal[]> e : byCat.entrySet()) {
            BigDecimal[] a = e.getValue();
            BigDecimal catPlanned = a[0];
            BigDecimal catUsed = a[1];
            double catUseRate = useRate(catPlanned, catUsed);
            boolean compliant = catUseRate >= 80.0 || Money.lte0(catPlanned);
            double extractRate = 0.0;
            if (!Money.lte0(totalBudget)) {
                extractRate = Math.round(Money.nz(catPlanned).divide(totalBudget, 4, RoundingMode.HALF_UP)
                        .doubleValue() * 10000.0) / 100.0;
            }
            String note = compliant ? "合规" : "使用率 " + catUseRate + "% 低于法规要求 80%，请加大" + e.getKey() + "实际支出";
            if (!compliant) {
                violations.add("【" + e.getKey() + "】" + note);
            }
            details.add(new FinanceCheckRow(checkPeriod, e.getKey(), catPlanned, totalBudget,
                    extractRate, catUseRate, compliant, note));
        }

        double overallUseRate = useRate(totalInvested, totalUsed);
        boolean overallCompliant = overallUseRate >= 80.0 || Money.lte0(totalInvested);
        if (!overallCompliant) {
            violations.add(0, "【总体】安全费整体使用率 " + overallUseRate + "% 未达 80%，存在法规合规风险");
        }
        if (!Money.lte0(totalBudget) && Money.gt(totalInvested, totalBudget)) {
            violations.add("【提取超限】安全费计划额（" + totalInvested + " 元）超出预算台账基准（" + totalBudget + " 元），请核实");
        }

        return ApiResp.ok(new FinanceCheckResult(
                java.time.LocalDate.now().toString(), checkPeriod,
                totalInvested, totalBudget, overallUseRate, overallCompliant,
                details, violations));
    }
}