package com.kaidi.oa.web;

import com.kaidi.oa.common.ApiResp;
import com.kaidi.oa.common.Money;
import com.kaidi.oa.domain.DevProject;
import com.kaidi.oa.domain.DevProjectBudget;
import com.kaidi.oa.repository.DevProjectBudgetRepository;
import com.kaidi.oa.repository.DevProjectRepository;
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.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.LocalDate;
import java.time.temporal.ChronoUnit;
import java.util.ArrayList;
import java.util.LinkedHashMap;
import java.util.List;
import java.util.Map;

/**
 * 创新研发中心 / 产品开发部 · 产品上市统计与研发投入三维分析（需求模块 10 报表与决策支持）。
 *
 * <p>补审计缺口"缺产品上市数量/上市周期/成功率端点；研发投入缺按部门维度统计"：
 * (1) /dev-launch-stats/launch-metrics — 新产品上市数量、上市周期（立项→发布天数）均值、成功率；
 * (2) /dev-launch-stats/by-dept — 研发投入按部门维度汇总（预算/实际）；
 * (3) /dev-launch-stats/by-product-line — 按产品线维度汇总（已有，本端点补 dept 维度）；
 * (4) /dev-launch-stats/cycle-detail — 每个已上市项目的立项→发布周期明细（可用于甘特分析）。
 *
 * <p>读口含成本汇总，已登记进 SENSITIVE_READ_PREFIXES（见 sharedFileSnippets）。
 */
@RestController
@RequestMapping("/api/oa/dev-launch-stats")
public class DevLaunchStatController {

    private final DevProjectRepository projectRepo;
    private final DevProjectBudgetRepository budgetRepo;

    public DevLaunchStatController(DevProjectRepository projectRepo,
                                   DevProjectBudgetRepository budgetRepo) {
        this.projectRepo = projectRepo;
        this.budgetRepo = budgetRepo;
    }

    // ======================================================================
    // 1. 产品上市核心指标
    // ======================================================================

    public record LaunchMetrics(
            int totalProjects,
            int launchedCount,
            int closedNotLaunched,
            double successRate,
            double avgCycleDays,
            double minCycleDays,
            double maxCycleDays,
            int noCycleDateCount) {
    }

    /**
     * 新产品上市数量、上市周期（立项 createdAt → launchDate，天数）、成功率。
     * successRate = 已上市 / 结题 × 100%（结题但未标记上市视为失败）。
     */
    @GetMapping("/launch-metrics")
    public ApiResp<LaunchMetrics> launchMetrics(
            @RequestParam(required = false) String productLine,
            @RequestParam(required = false) String dept) {
        List<DevProject> projects = projectRepo.findAll();

        int totalClosed = 0;
        int launched = 0;
        List<Long> cycleDaysList = new ArrayList<>();
        int noCycleDate = 0;

        for (DevProject p : projects) {
            if (productLine != null && !productLine.isBlank()
                    && !productLine.equals(p.getProductLine())) continue;
            if (dept != null && !dept.isBlank()
                    && !dept.equals(p.getDept()) && !dept.equals(p.getDepartment())) continue;

            boolean isClosed = "结题".equals(p.getStage());
            if (isClosed) totalClosed++;

            if (p.isProductLaunched()) {
                launched++;
                // 计算周期：createdAt → launchDate。
                if (p.getCreatedAt() != null && p.getLaunchDate() != null
                        && !p.getLaunchDate().isBlank()) {
                    try {
                        LocalDate start = p.getCreatedAt().atZone(java.time.ZoneId.systemDefault())
                                .toLocalDate();
                        LocalDate end = LocalDate.parse(p.getLaunchDate());
                        long days = ChronoUnit.DAYS.between(start, end);
                        if (days >= 0) cycleDaysList.add(days);
                    } catch (Exception ignored) {
                        noCycleDate++;
                    }
                } else {
                    noCycleDate++;
                }
            }
        }

        double successRate = totalClosed == 0 ? 0
                : round2((double) launched / totalClosed * 100);
        double avgCycle = cycleDaysList.isEmpty() ? 0
                : round2(cycleDaysList.stream().mapToLong(Long::longValue).average().orElse(0));
        double minCycle = cycleDaysList.isEmpty() ? 0
                : cycleDaysList.stream().mapToLong(Long::longValue).min().orElse(0);
        double maxCycle = cycleDaysList.isEmpty() ? 0
                : cycleDaysList.stream().mapToLong(Long::longValue).max().orElse(0);

        return ApiResp.ok(new LaunchMetrics(
                (int) projectRepo.count(), launched,
                totalClosed - launched,
                successRate, avgCycle, minCycle, maxCycle, noCycleDate));
    }

    // ======================================================================
    // 2. 按部门维度统计研发投入（补"三维：项目/产品线/部门"中的部门维度）
    // ======================================================================

    public record DeptStat(String dept, int projectCount, int launchedCount,
                           double budget, double actual, double execRate) {
    }

    @GetMapping("/by-dept")
    public ApiResp<List<DeptStat>> byDept() {
        List<DevProject> projects = projectRepo.findAll();

        // 预算/实际按项目 id 聚合。
        Map<Long, BigDecimal> budgetByProject = new LinkedHashMap<>();
        Map<Long, BigDecimal> actualByProject = new LinkedHashMap<>();
        for (DevProjectBudget b : budgetRepo.findAll()) {
            budgetByProject.merge(b.getDevProjectId(), Money.nz(b.getBudgetAmount()), Money::add);
            actualByProject.merge(b.getDevProjectId(), Money.nz(b.getActualAmount()), Money::add);
        }

        // 按部门分组。
        Map<String, int[]> countByDept = new LinkedHashMap<>();   // [0]=total [1]=launched
        Map<String, BigDecimal> budgetByDept = new LinkedHashMap<>();
        Map<String, BigDecimal> actualByDept = new LinkedHashMap<>();

        for (DevProject p : projects) {
            String d = notBlank(p.getDept(), notBlank(p.getDepartment(), "未分类"));
            int[] cnt = countByDept.computeIfAbsent(d, k -> new int[2]);
            cnt[0]++;
            if (p.isProductLaunched()) cnt[1]++;
            BigDecimal bud = budgetByProject.getOrDefault(p.getId(), Money.nz(p.getBudget()));
            BigDecimal act = actualByProject.getOrDefault(p.getId(), Money.ZERO);
            budgetByDept.merge(d, bud, Money::add);
            actualByDept.merge(d, act, Money::add);
        }

        List<DeptStat> stats = new ArrayList<>();
        for (Map.Entry<String, int[]> e : countByDept.entrySet()) {
            BigDecimal bud = budgetByDept.getOrDefault(e.getKey(), Money.ZERO);
            BigDecimal act = actualByDept.getOrDefault(e.getKey(), Money.ZERO);
            double rate = bud.signum() == 0 ? 0
                    : round2(act.doubleValue() / bud.doubleValue() * 100);
            stats.add(new DeptStat(e.getKey(), e.getValue()[0], e.getValue()[1],
                    bud.doubleValue(), act.doubleValue(), rate));
        }
        return ApiResp.ok(stats);
    }

    // ======================================================================
    // 3. 上市周期明细（每个已上市项目）
    // ======================================================================

    public record CycleDetail(Long id, String code, String name, String productLine,
                              String dept, String createdDate, String launchDate,
                              long cycleDays, String projectType) {
    }

    @GetMapping("/cycle-detail")
    public ApiResp<List<CycleDetail>> cycleDetail() {
        List<DevProject> projects = projectRepo.findAll();
        List<CycleDetail> details = new ArrayList<>();
        for (DevProject p : projects) {
            if (!p.isProductLaunched()) continue;
            String createdDate = p.getCreatedAt() != null
                    ? p.getCreatedAt().atZone(java.time.ZoneId.systemDefault())
                            .toLocalDate().toString()
                    : null;
            long days = 0;
            if (createdDate != null && p.getLaunchDate() != null && !p.getLaunchDate().isBlank()) {
                try {
                    days = ChronoUnit.DAYS.between(LocalDate.parse(createdDate),
                            LocalDate.parse(p.getLaunchDate()));
                } catch (Exception ignored) {
                    days = -1;
                }
            }
            details.add(new CycleDetail(p.getId(), p.getCode(), p.getName(),
                    p.getProductLine(),
                    notBlank(p.getDept(), p.getDepartment()),
                    createdDate, p.getLaunchDate(), days, p.getProjectType()));
        }
        return ApiResp.ok(details);
    }

    // ======================================================================
    // 4. 标记项目已上市（写口，触发 productLaunched=true + launchDate 回填）
    // ======================================================================

    public record MarkLaunchRequest(String launchDate, String dept) {
    }

    /**
     * 标记研发项目为「已上市」（量产发布）：回填 launchDate + productLaunched=true。
     * 须项目处于结题或研发中阶段。写口受 ADMIN/APPROVER 保护。
     */
    @org.springframework.web.bind.annotation.PostMapping("/{id}/mark-launched")
    @org.springframework.transaction.annotation.Transactional
    public ApiResp<DevProject> markLaunched(
            @PathVariable Long id,
            @RequestBody(required = false) MarkLaunchRequest req) {
        DevProject p = projectRepo.findById(id)
                .orElseThrow(() -> new com.kaidi.oa.common.NotFoundException("研发立项不存在：" + id));
        if (p.isProductLaunched()) {
            throw new com.kaidi.oa.common.ApiException(409, "该项目已标记上市（上市日期：" + p.getLaunchDate() + "）");
        }
        if (!"结题".equals(p.getStage()) && !"研发中".equals(p.getStage())) {
            throw new com.kaidi.oa.common.ApiException(400, "仅结题或研发中阶段的项目可标记上市，当前阶段：" + p.getStage());
        }
        p.setProductLaunched(true);
        String ld = (req != null && req.launchDate() != null && !req.launchDate().isBlank())
                ? req.launchDate()
                : LocalDate.now().toString();
        p.setLaunchDate(ld);
        if (req != null && req.dept() != null && !req.dept().isBlank()) {
            p.setDept(req.dept());
        }
        return ApiResp.ok(projectRepo.save(p));
    }

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

    private static double round2(double v) {
        return Math.round(v * 100d) / 100d;
    }

    private static String notBlank(String v, String dft) {
        return v == null || v.isBlank() ? dft : v;
    }
}