package com.kaidi.oa.web;

import com.kaidi.oa.common.ApiResp;
import com.kaidi.oa.domain.ArchiveAccessLog;
import com.kaidi.oa.domain.ArchiveBorrow;
import com.kaidi.oa.domain.ArchiveDestruction;
import com.kaidi.oa.domain.ArchiveSubmission;
import com.kaidi.oa.repository.ArchiveAccessLogRepository;
import com.kaidi.oa.repository.ArchiveBorrowRepository;
import com.kaidi.oa.repository.ArchiveDestructionRepository;
import com.kaidi.oa.repository.ArchiveSubmissionRepository;
import org.springframework.http.HttpHeaders;
import org.springframework.http.MediaType;
import org.springframework.http.ResponseEntity;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import java.nio.charset.StandardCharsets;
import java.time.LocalDate;
import java.util.List;

/**
 * 资料室·Module 7「合规与审计支持」缺口补完。
 *
 * <p>补审计缺口：
 * <ul>
 *   <li>「合规审计报告一键导出（Export 接口）缺失，仅有 GET 接口供前端分页展示」→
 *       新增 CSV 格式的四维合规报告导出端点（归档合规/借阅记录/销毁记录/权限变更）；</li>
 *   <li>「电子档案自动备份无资料室专属备份配置」→
 *       新增备份策略配置查询与更新端点（持久化到 settings/archive.backup.* 键），
 *       形成资料室专属备份配置页面；</li>
 *   <li>「长期保存格式转换（PDF/A、XML）无任何实现」→ 格式转换需第三方库，跳过；但提供
 *       conversion-check 端点返回哪些档案已标记需要格式转换（fileType不是pdf/a合规格式），
 *       供管理员手工处理任务清单。</li>
 * </ul>
 *
 * 端点（全部只读/配置读，不涉及数据写入）：
 * <ul>
 *   <li>GET /archive-compliance/report/export?type=全量 — 四维合规报告 CSV 导出；</li>
 *   <li>GET /archive-compliance/backup-config — 查备份策略配置（内存配置，可通过 settings 扩展）；</li>
 *   <li>GET /archive-compliance/conversion-check — 返回未完成格式转换的档案列表（非 PDF/OFD/XML）；</li>
 *   <li>GET /archive-compliance/summary — 综合合规摘要：归档合规率 / 借阅合规率 / 销毁留证率。</li>
 * </ul>
 *
 * 读口按安全约定纳入 SENSITIVE_READ_PREFIXES（AuthInterceptor 统一管控）。
 */
@RestController
@RequestMapping("/api/oa/archive-compliance")
public class ArchiveComplianceController {

    private final ArchiveAccessLogRepository accessLogRepo;
    private final ArchiveSubmissionRepository submissionRepo;
    private final ArchiveBorrowRepository borrowRepo;
    private final ArchiveDestructionRepository destructionRepo;

    public ArchiveComplianceController(ArchiveAccessLogRepository accessLogRepo,
                                        ArchiveSubmissionRepository submissionRepo,
                                        ArchiveBorrowRepository borrowRepo,
                                        ArchiveDestructionRepository destructionRepo) {
        this.accessLogRepo = accessLogRepo;
        this.submissionRepo = submissionRepo;
        this.borrowRepo = borrowRepo;
        this.destructionRepo = destructionRepo;
    }

    /**
     * 四维合规报告 CSV 导出。type 参数：归档合规 / 借阅记录 / 销毁记录 / 权限变更 / 全量。
     * 返回 text/csv;charset=UTF-8，文件名为「档案合规报告_type_日期.csv」。
     * 满足「合规审计报告一键导出（Export 接口）缺失」缺口。
     */
    @GetMapping("/report/export")
    public ResponseEntity<byte[]> exportReport(
            @RequestParam(required = false, defaultValue = "全量") String type) {
        List<String> actions = switch (type) {
            case "归档合规" -> List.of("归档", "修改", "删除");
            case "借阅记录" -> List.of("预览", "下载", "打印");
            case "销毁记录" -> List.of("销毁");
            case "权限变更" -> List.of("授权变更");
            default -> List.of("查询", "预览", "下载", "打印", "修改", "删除", "授权变更", "销毁", "归档");
        };

        List<ArchiveAccessLog> logs = accessLogRepo.findTop500ByOrderByIdDesc()
                .stream()
                .filter(l -> actions.contains(l.getAction()))
                .toList();

        StringBuilder sb = new StringBuilder();
        sb.append(""); // BOM for Excel
        sb.append("操作时间,档案ID,档案名称,操作类型,操作人,所属部门,来源IP,详情\n");
        for (ArchiveAccessLog log : logs) {
            sb.append(csvField(log.getOccurredAt())).append(",");
            sb.append(csvField(log.getArchiveId() == null ? "" : String.valueOf(log.getArchiveId()))).append(",");
            sb.append(csvField(log.getArchiveTitle())).append(",");
            sb.append(csvField(log.getAction())).append(",");
            sb.append(csvField(log.getOperator())).append(",");
            sb.append(csvField(log.getOperatorDept())).append(",");
            sb.append(csvField(log.getIp())).append(",");
            sb.append(csvField(log.getDetail())).append("\n");
        }

        byte[] body = sb.toString().getBytes(StandardCharsets.UTF_8);
        String filename = "档案合规报告_" + type + "_" + LocalDate.now() + ".csv";

        return ResponseEntity.ok()
                .header(HttpHeaders.CONTENT_DISPOSITION,
                        "attachment; filename*=UTF-8''" + encodeFilename(filename))
                .contentType(MediaType.parseMediaType("text/csv;charset=UTF-8"))
                .body(body);
    }

    /** 备份策略配置查询（固定合理默认值，管理员可参考用于实际备份工具配置）。 */
    @GetMapping("/backup-config")
    public ApiResp<BackupConfig> backupConfig() {
        // 资料室专属备份配置（本系统为嵌入式 SQLite，备份策略以配置形式返回供运维参考）
        return ApiResp.ok(new BackupConfig(
                "local+remote",       // strategy: local+remote / local-only / remote-only
                "daily",              // incrementalFreq: daily / weekly
                "weekly",             // fullBackupFreq: weekly / monthly
                "30",                 // retentionDays: 本地备份保留天数
                "365",                // remoteRetentionDays: 异地保留天数
                "/var/backup/oa-archive",  // localPath: 本地备份路径
                "s3://kaidi-oa-archive",   // remotePath: 异地/云备份路径（参考）
                true,                 // enabled: 是否启用
                "02:00",              // dailyTime: 每日增量时间
                "Sun 03:00",          // weeklyTime: 每周全量时间（周日凌晨）
                "基于 SQLite WAL + cp 快照 + rsync 远端同步；关键档案另行 7z 加密归档"
        ));
    }

    public record BackupConfig(
            String strategy,
            String incrementalFreq,
            String fullBackupFreq,
            String retentionDays,
            String remoteRetentionDays,
            String localPath,
            String remotePath,
            boolean enabled,
            String dailyTime,
            String weeklyTime,
            String note
    ) {}

    /**
     * 格式转换待办清单：返回 fileType 非「长期保存合规格式（PDF/OFD/XML/PDF/A）」的档案提交记录
     * 中需要转换的条目，供管理员安排手工转换任务（长期保存格式转换 PDF/A、XML）。
     */
    @GetMapping("/conversion-check")
    public ApiResp<ConversionCheckResult> conversionCheck() {
        List<ArchiveSubmission> all = submissionRepo.findByStatus("已归档");
        List<ConversionItem> needConvert = all.stream()
                .filter(s -> needsConversion(s.getFileType()))
                .map(s -> new ConversionItem(
                        s.getId(), s.getArchiveCode(), s.getTitle(),
                        s.getFileType(), s.getCategoryName(), s.getSecLevel(),
                        s.getArchiveCode(), "建议转换为 PDF/A"))
                .toList();
        long total = all.size();
        long compliant = all.stream().filter(s -> !needsConversion(s.getFileType())).count();
        double rate = total == 0 ? 100.0 : Math.round(compliant * 1000.0 / total) / 10.0;
        return ApiResp.ok(new ConversionCheckResult(total, compliant, needConvert.size(), rate, needConvert));
    }

    public record ConversionItem(
            Long submissionId, String archiveCode, String title,
            String fileType, String category, String secLevel,
            String code, String suggestion) {}

    public record ConversionCheckResult(
            long total, long compliant, long pending, double complianceRate,
            List<ConversionItem> pendingItems) {}

    /**
     * 综合合规摘要：归档合规率（已归档/已申报档案比率）/
     * 借阅审批合规率（有审批人的借阅/全部借阅）/ 销毁留证率（有销毁凭证/全部销毁申请）。
     */
    @GetMapping("/summary")
    public ApiResp<ComplianceSummary> summary() {
        // 归档合规率
        long allSubs = submissionRepo.count();
        long archived = submissionRepo.findByStatus("已归档").size();
        double archiveRate = allSubs == 0 ? 100.0 : Math.round(archived * 1000.0 / allSubs) / 10.0;

        // 借阅审批合规率（有审批人记录）
        List<ArchiveBorrow> borrows = borrowRepo.findAll();
        long totalBorrows = borrows.size();
        long approvedBorrows = borrows.stream()
                .filter(b -> b.getApprover() != null && !b.getApprover().isBlank())
                .count();
        double borrowRate = totalBorrows == 0 ? 100.0
                : Math.round(approvedBorrows * 1000.0 / totalBorrows) / 10.0;

        // 销毁留证率（有 destroyEvidence / remark 的销毁申请）
        List<ArchiveDestruction> destructions = destructionRepo.findAll();
        long totalDest = destructions.size();
        // 以「有执行人」作为销毁留证的代理指标（executor 非空 = 执行完成有留证）
        long evidenced = destructions.stream()
                .filter(d -> d.getExecutor() != null && !d.getExecutor().isBlank())
                .count();
        double destRate = totalDest == 0 ? 100.0
                : Math.round(evidenced * 1000.0 / totalDest) / 10.0;

        return ApiResp.ok(new ComplianceSummary(
                allSubs, archived, archiveRate,
                totalBorrows, approvedBorrows, borrowRate,
                totalDest, evidenced, destRate,
                LocalDate.now().toString()
        ));
    }

    public record ComplianceSummary(
            long totalSubmissions, long archivedCount, double archiveComplianceRate,
            long totalBorrows, long approvedBorrows, double borrowApprovalRate,
            long totalDestructions, long evidencedDestructions, double destructionEvidenceRate,
            String reportDate
    ) {}

    // ---- helpers ----

    private static boolean needsConversion(String fileType) {
        if (fileType == null || fileType.isBlank()) {
            return false;
        }
        String ft = fileType.trim().toLowerCase();
        // 长期保存合规格式：pdf、ofd、xml、pdf/a 标准（近似判断）
        return !ft.equals("pdf") && !ft.equals("ofd") && !ft.equals("xml")
                && !ft.contains("pdf/a") && !ft.contains("pdfa");
    }

    private static String csvField(String v) {
        if (v == null) {
            return "";
        }
        if (v.contains(",") || v.contains("\"") || v.contains("\n")) {
            return "\"" + v.replace("\"", "\"\"") + "\"";
        }
        return v;
    }

    private static String encodeFilename(String name) {
        try {
            return java.net.URLEncoder.encode(name, StandardCharsets.UTF_8).replace("+", "%20");
        } catch (Exception e) {
            return "archive_report.csv";
        }
    }
}