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.FinVoucherTemplate;
import com.kaidi.oa.domain.Voucher;
import com.kaidi.oa.repository.FinVoucherTemplateRepository;
import com.kaidi.oa.repository.VoucherRepository;
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.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.time.Instant;
import java.time.LocalDate;
import java.util.List;
import java.util.Map;

/**
 * 财务部·凭证模板管理与期末结转（财务总账深化）。
 *
 * 审计缺口：无凭证模板；无自动/自定义结转损益；无期末处理。
 *
 * 本控制器提供：
 *  1. 凭证模板 CRUD（常用业务：计提折旧/摊销/结转损益/结转研发/分摊制造费/期末调汇）。
 *  2. POST /{id}/apply —— 按模板一键生成草稿凭证（摘要变量替换 ${period}/${amount}）。
 *  3. POST /period-close —— 月末结转损益：自动生成一批结转凭证（收入→本年利润/成本→本年利润），
 *     返回生成的凭证列表（草稿状态，需财务审核过账）。
 *
 * 写口：AuthInterceptor FINANCE_PREFIXES(/api/oa/fin-voucher-templates) 限 ADMIN/APPROVER。
 * 读口：SENSITIVE_READ_PREFIXES 同门槛（含科目信息，属机密财务）。
 */
@RestController
@RequestMapping("/api/oa/fin-voucher-templates")
public class FinVoucherTemplateController {

    private final FinVoucherTemplateRepository templateRepo;
    private final VoucherRepository voucherRepo;

    public FinVoucherTemplateController(FinVoucherTemplateRepository templateRepo,
                                        VoucherRepository voucherRepo) {
        this.templateRepo = templateRepo;
        this.voucherRepo = voucherRepo;
    }

    // ---------- 模板 CRUD ----------

    @GetMapping
    public ApiResp<List<FinVoucherTemplate>> list(
            @RequestParam(required = false) String templateType,
            @RequestParam(required = false) Boolean enabled) {
        if (templateType != null && !templateType.isBlank()) {
            return ApiResp.ok(templateRepo.findByTemplateType(templateType));
        }
        if (enabled != null) {
            return ApiResp.ok(templateRepo.findByEnabled(enabled));
        }
        return ApiResp.ok(templateRepo.findAll());
    }

    @GetMapping("/{id}")
    public ApiResp<FinVoucherTemplate> get(@PathVariable Long id) {
        return ApiResp.ok(templateRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("凭证模板不存在: " + id)));
    }

    public record TemplateRequest(
            String name, String templateType, String debitAccount, String creditAccount,
            String summaryTemplate, String amountSource, Boolean enabled, String createdBy) {
    }

    @PostMapping
    public ApiResp<FinVoucherTemplate> create(@RequestBody TemplateRequest req) {
        if (req.name() == null || req.name().isBlank()) {
            throw new ApiException(400, "模板名称不能为空");
        }
        FinVoucherTemplate t = new FinVoucherTemplate();
        t.setCode("TMPl-" + (templateRepo.count() + 1));
        t.setName(req.name());
        t.setTemplateType(req.templateType() == null ? FinVoucherTemplate.TYPE_MANUAL : req.templateType());
        t.setDebitAccount(req.debitAccount());
        t.setCreditAccount(req.creditAccount());
        t.setSummaryTemplate(req.summaryTemplate() == null ? req.name() : req.summaryTemplate());
        t.setAmountSource(req.amountSource() == null ? "手填" : req.amountSource());
        t.setEnabled(req.enabled() == null ? Boolean.TRUE : req.enabled());
        t.setCreatedBy(req.createdBy());
        t.setCreatedAt(Instant.now());
        return ApiResp.ok(templateRepo.save(t));
    }

    @PutMapping("/{id}")
    public ApiResp<FinVoucherTemplate> update(@PathVariable Long id, @RequestBody TemplateRequest req) {
        FinVoucherTemplate t = templateRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("凭证模板不存在: " + id));
        if (req.name() != null && !req.name().isBlank()) t.setName(req.name());
        if (req.templateType() != null) t.setTemplateType(req.templateType());
        if (req.debitAccount() != null) t.setDebitAccount(req.debitAccount());
        if (req.creditAccount() != null) t.setCreditAccount(req.creditAccount());
        if (req.summaryTemplate() != null) t.setSummaryTemplate(req.summaryTemplate());
        if (req.amountSource() != null) t.setAmountSource(req.amountSource());
        if (req.enabled() != null) t.setEnabled(req.enabled());
        return ApiResp.ok(templateRepo.save(t));
    }

    @DeleteMapping("/{id}")
    public ApiResp<Void> delete(@PathVariable Long id) {
        templateRepo.findById(id).orElseThrow(() -> new NotFoundException("凭证模板不存在: " + id));
        templateRepo.deleteById(id);
        return ApiResp.ok(null);
    }

    // ---------- 按模板生成草稿凭证 ----------

    public record ApplyRequest(Double amount, String period, String preparer) {}

    @PostMapping("/{id}/apply")
    @Transactional
    public ApiResp<Voucher> apply(@PathVariable Long id, @RequestBody ApplyRequest req) {
        FinVoucherTemplate t = templateRepo.findById(id)
                .orElseThrow(() -> new NotFoundException("凭证模板不存在: " + id));
        if (!Boolean.TRUE.equals(t.getEnabled())) {
            throw new ApiException(400, "该模板已停用，无法生成凭证");
        }
        if (req.amount() == null || req.amount() <= 0) {
            throw new ApiException(400, "金额必须大于 0");
        }

        String period = req.period() != null ? req.period() : LocalDate.now().toString().substring(0, 7);
        String summary = (t.getSummaryTemplate() == null ? t.getName() : t.getSummaryTemplate())
                .replace("${period}", period)
                .replace("${amount}", String.format("%.2f", req.amount()));

        Voucher v = new Voucher();
        v.setVoucherNo("TMPl-" + t.getCode() + "-" + System.currentTimeMillis() % 10000);
        v.setVoucherDate(LocalDate.now().toString());
        v.setSummary(summary);
        v.setDebitAccount(t.getDebitAccount());
        v.setCreditAccount(t.getCreditAccount());
        v.setAmount(Money.of(req.amount()));
        v.setStatus(Voucher.S_DRAFT);
        v.setPreparer(req.preparer());
        v.setReversed(Boolean.FALSE);
        v.setIsReversal(Boolean.FALSE);
        v.setCreatedAt(Instant.now());
        return ApiResp.ok(voucherRepo.save(v));
    }

    // ---------- 月末结转损益 ----------

    public record PeriodCloseRequest(
            String period, String preparer,
            Double totalRevenue, Double totalCost, Double totalExpense) {}

    /**
     * 月末结转损益：生成三张草稿凭证（借收入/贷本年利润；借本年利润/贷成本；借本年利润/贷费用），
     * 财务确认后逐张审核过账完成结账前检查。
     */
    @PostMapping("/period-close")
    @Transactional
    public ApiResp<List<Voucher>> periodClose(@RequestBody PeriodCloseRequest req) {
        if (req.period() == null || req.period().isBlank()) {
            throw new ApiException(400, "结转期间不能为空，格式 yyyy-MM");
        }
        String period = req.period();
        String preparer = req.preparer() == null ? "系统自动" : req.preparer();

        double revenue = req.totalRevenue() == null ? 0 : req.totalRevenue();
        double cost    = req.totalCost()    == null ? 0 : req.totalCost();
        double expense = req.totalExpense() == null ? 0 : req.totalExpense();

        List<Voucher> generated = new java.util.ArrayList<>();

        // 凭证1：结转收入 → 本年利润（借 6001/主营业务收入，贷 4103/本年利润）
        if (revenue > 0) {
            Voucher v1 = buildTransferVoucher(
                    "JZ-" + period + "-01", period,
                    period + " 月结转主营业务收入",
                    "6001", "4103", revenue, preparer);
            generated.add(voucherRepo.save(v1));
        }
        // 凭证2：结转成本 → 本年利润（借 4103/本年利润，贷 6401/主营业务成本）
        if (cost > 0) {
            Voucher v2 = buildTransferVoucher(
                    "JZ-" + period + "-02", period,
                    period + " 月结转主营业务成本",
                    "4103", "6401", cost, preparer);
            generated.add(voucherRepo.save(v2));
        }
        // 凭证3：结转期间费用 → 本年利润（借 4103/本年利润，贷 6601/管理费用+销售费用+财务费用汇总）
        if (expense > 0) {
            Voucher v3 = buildTransferVoucher(
                    "JZ-" + period + "-03", period,
                    period + " 月结转期间费用",
                    "4103", "6601", expense, preparer);
            generated.add(voucherRepo.save(v3));
        }

        if (generated.isEmpty()) {
            throw new ApiException(400, "收入/成本/费用至少填写一项");
        }
        return ApiResp.ok(generated);
    }

    private Voucher buildTransferVoucher(String voucherNo, String period, String summary,
                                          String debit, String credit, double amount, String preparer) {
        Voucher v = new Voucher();
        v.setVoucherNo(voucherNo);
        v.setVoucherDate(LocalDate.now().toString());
        v.setSummary(summary);
        v.setDebitAccount(debit);
        v.setCreditAccount(credit);
        v.setAmount(Money.of(amount));
        v.setStatus(Voucher.S_DRAFT);
        v.setPreparer(preparer);
        v.setReversed(Boolean.FALSE);
        v.setIsReversal(Boolean.FALSE);
        v.setCreatedAt(Instant.now());
        return v;
    }

    // ---------- 模板类型列表（前端下拉用） ----------
    @GetMapping("/template-types")
    public ApiResp<List<String>> templateTypes() {
        return ApiResp.ok(List.of(
                FinVoucherTemplate.TYPE_MANUAL,
                FinVoucherTemplate.TYPE_DEPREC,
                FinVoucherTemplate.TYPE_AMORT,
                FinVoucherTemplate.TYPE_TRANSFER,
                FinVoucherTemplate.TYPE_RD,
                FinVoucherTemplate.TYPE_MFG,
                FinVoucherTemplate.TYPE_FX
        ));
    }
}