/*
 * 自然写教学资源管理与内容分发系统软件 V1.0
 * service/AuditService.java - 内容审核服务
 */
package com.writech.resource.service;

import java.util.*;
import java.util.logging.Logger;

/**
 * 内容审核服务
 *
 * 教师上传的资源需经过管理员审核后才能被其他用户检索和使用。
 * 审核流程支持：
 * - 自动预审（AI内容安全检测）
 * - 人工审核（管理员审核通过/驳回/退回修改）
 * - 审核记录全程留痕
 * - 批量审核
 */
public class AuditService {

    private static final Logger logger =
        Logger.getLogger(AuditService.class.getName());

    // ============================================================
    //  审核数据模型
    // ============================================================

    /** 审核操作类型 */
    public enum AuditAction {
        APPROVE,    // 审核通过
        REJECT,     // 驳回
        RETURN,     // 退回修改
        WITHDRAW    // 上传者撤回
    }

    /** 审核记录（对应MySQL audit_record表） */
    public static class AuditRecord {
        private String id;
        private String resourceId;
        private String resourceName;
        private String auditorId;       // 审核人ID
        private String auditorName;     // 审核人姓名
        private AuditAction action;
        private String comment;         // 审核意见
        private String preStatus;       // 审核前状态
        private String postStatus;      // 审核后状态
        private Date createdAt;

        // Getter/Setter
        public String getId() { return id; }
        public void setId(String id) { this.id = id; }
        public String getResourceId() { return resourceId; }
        public void setResourceId(String rid) { this.resourceId = rid; }
        public String getResourceName() { return resourceName; }
        public void setResourceName(String name) { this.resourceName = name; }
        public String getAuditorId() { return auditorId; }
        public void setAuditorId(String id) { this.auditorId = id; }
        public AuditAction getAction() { return action; }
        public void setAction(AuditAction action) { this.action = action; }
        public String getComment() { return comment; }
        public void setComment(String comment) { this.comment = comment; }
        public Date getCreatedAt() { return createdAt; }
    }

    /** 审核请求 */
    public static class AuditRequest {
        private String resourceId;
        private AuditAction action;
        private String comment;
        private String auditorId;

        public String getResourceId() { return resourceId; }
        public void setResourceId(String id) { this.resourceId = id; }
        public AuditAction getAction() { return action; }
        public void setAction(AuditAction action) { this.action = action; }
        public String getComment() { return comment; }
        public void setComment(String c) { this.comment = c; }
        public String getAuditorId() { return auditorId; }
        public void setAuditorId(String id) { this.auditorId = id; }
    }

    /** 自动预审结果 */
    public static class PreAuditResult {
        private boolean safe;
        private double safeScore;       // 安全评分（0-1）
        private List<String> warnings;  // 警告信息
        private String category;        // 内容分类

        public PreAuditResult(boolean safe, double score) {
            this.safe = safe;
            this.safeScore = score;
            this.warnings = new ArrayList<>();
        }

        public boolean isSafe() { return safe; }
        public double getSafeScore() { return safeScore; }
        public List<String> getWarnings() { return warnings; }
        public void addWarning(String w) { this.warnings.add(w); }
    }

    // ============================================================
    //  审核业务方法
    // ============================================================

    /**
     * 执行审核操作 PUT /api/v1/resource/audit/{id}
     *
     * @param request 审核请求
     * @return 审核结果
     */
    public Map<String, Object> performAudit(AuditRequest request) {
        logger.info(String.format(
            "执行审核: resource=%s, action=%s, auditor=%s",
            request.getResourceId(), request.getAction(), request.getAuditorId()
        ));

        // 查询资源当前状态
        // ResourceMetadata resource = resourceMapper.selectById(request.getResourceId());
        // if (resource == null) {
        //     return errorResponse(404, "资源不存在");
        // }

        // 状态机校验：只有PENDING状态可被审核
        // if (resource.getAuditStatus() != AuditStatus.PENDING) {
        //     return errorResponse(400, "当前状态不可审核");
        // }

        // 创建审核记录
        AuditRecord record = new AuditRecord();
        record.setId(UUID.randomUUID().toString().replace("-", ""));
        record.setResourceId(request.getResourceId());
        record.setAuditorId(request.getAuditorId());
        record.setAction(request.getAction());
        record.setComment(request.getComment());
        record.setPreStatus("PENDING");

        // 根据审核动作更新资源状态
        String newStatus;
        switch (request.getAction()) {
            case APPROVE:
                newStatus = "APPROVED";
                // 审核通过后，同步更新Elasticsearch索引状态
                // updateEsAuditStatus(request.getResourceId(), "APPROVED");
                // 预热CDN缓存（使资源可被终端下载）
                // cdnService.preheatResource(request.getResourceId());
                break;
            case REJECT:
                newStatus = "REJECTED";
                break;
            case RETURN:
                newStatus = "PENDING";  // 退回修改后重新提交
                break;
            default:
                newStatus = "PENDING";
        }

        record.setPostStatus(newStatus);

        // 持久化
        // auditRecordMapper.insert(record);
        // resourceMapper.updateAuditStatus(request.getResourceId(), newStatus);

        // 通知上传者审核结果（消息推送）
        // notifyUploader(request.getResourceId(), request.getAction(), request.getComment());

        Map<String, Object> result = new HashMap<>();
        result.put("code", 0);
        result.put("message", "审核操作成功");
        result.put("data", Map.of(
            "resource_id", request.getResourceId(),
            "new_status", newStatus,
            "audit_record_id", record.getId()
        ));
        return result;
    }

    /**
     * 批量审核
     *
     * @param resourceIds 资源ID列表
     * @param action 审核动作
     * @param comment 审核意见
     * @param auditorId 审核人
     * @return 批量审核结果
     */
    public Map<String, Object> batchAudit(
        List<String> resourceIds,
        AuditAction action,
        String comment,
        String auditorId
    ) {
        logger.info(String.format(
            "批量审核: count=%d, action=%s", resourceIds.size(), action
        ));

        int successCount = 0;
        int failCount = 0;
        List<String> failedIds = new ArrayList<>();

        for (String resourceId : resourceIds) {
            try {
                AuditRequest request = new AuditRequest();
                request.setResourceId(resourceId);
                request.setAction(action);
                request.setComment(comment);
                request.setAuditorId(auditorId);

                Map<String, Object> result = performAudit(request);
                if ((int) result.get("code") == 0) {
                    successCount++;
                } else {
                    failCount++;
                    failedIds.add(resourceId);
                }
            } catch (Exception e) {
                failCount++;
                failedIds.add(resourceId);
                logger.warning("批量审核失败: resource=" + resourceId + ", error=" + e.getMessage());
            }
        }

        Map<String, Object> result = new HashMap<>();
        result.put("code", 0);
        result.put("data", Map.of(
            "total", resourceIds.size(),
            "success", successCount,
            "failed", failCount,
            "failed_ids", failedIds
        ));
        return result;
    }

    /**
     * AI自动预审
     *
     * 在人工审核前，自动进行内容安全检测：
     * - 文本内容是否包含违禁词
     * - 图片是否包含不当内容
     * - 文件格式是否合规
     * - 文件大小是否超限
     *
     * @param resourceId 资源ID
     * @return 预审结果
     */
    public PreAuditResult performPreAudit(String resourceId) {
        logger.info("AI预审: resource=" + resourceId);

        PreAuditResult result = new PreAuditResult(true, 1.0);

        // 1. 文件格式和大小检查
        // ResourceMetadata resource = resourceMapper.selectById(resourceId);
        // if (resource.getFileSize() > MAX_FILE_SIZE) {
        //     result = new PreAuditResult(false, 0.0);
        //     result.addWarning("文件大小超过限制");
        //     return result;
        // }

        // 2. 文本内容安全检测（提取PDF/PPT中的文字进行违禁词检查）
        // String textContent = extractTextContent(resource.getFileKey());
        // ContentSafetyResult textSafety = contentSafetyApi.checkText(textContent);
        // if (!textSafety.isSafe()) {
        //     result.addWarning("文本内容包含敏感词: " + textSafety.getDetails());
        // }

        // 3. 图片内容安全检测（提取文档中的图片进行AI审核）
        // List<byte[]> images = extractImages(resource.getFileKey());
        // for (byte[] image : images) {
        //     ImageSafetyResult imageSafety = contentSafetyApi.checkImage(image);
        //     if (!imageSafety.isSafe()) {
        //         result.addWarning("图片内容不合规: " + imageSafety.getCategory());
        //     }
        // }

        // 综合评分
        if (!result.getWarnings().isEmpty()) {
            double penalty = result.getWarnings().size() * 0.2;
            double finalScore = Math.max(0.0, 1.0 - penalty);
            result = new PreAuditResult(finalScore >= 0.6, finalScore);
        }

        logger.info(String.format(
            "预审完成: resource=%s, safe=%b, score=%.2f",
            resourceId, result.isSafe(), result.getSafeScore()
        ));

        return result;
    }

    /**
     * 查询审核记录列表
     *
     * @param resourceId 资源ID（可选，为空则查所有）
     * @param auditorId 审核人ID（可选）
     * @param page 页码
     * @param pageSize 每页大小
     * @return 审核记录列表
     */
    public Map<String, Object> queryAuditRecords(
        String resourceId,
        String auditorId,
        int page,
        int pageSize
    ) {
        logger.info(String.format(
            "查询审核记录: resource=%s, auditor=%s, page=%d",
            resourceId, auditorId, page
        ));

        // List<AuditRecord> records = auditRecordMapper.selectByCondition(
        //     resourceId, auditorId, page, pageSize
        // );
        // int total = auditRecordMapper.countByCondition(resourceId, auditorId);

        Map<String, Object> result = new HashMap<>();
        result.put("code", 0);
        result.put("data", Map.of(
            "total", 0,
            "page", page,
            "items", new ArrayList<>()
        ));
        return result;
    }

    /**
     * 获取待审核资源数量（仪表盘统计用）
     */
    public Map<String, Object> getAuditStats() {
        // int pendingCount = resourceMapper.countByStatus("PENDING");
        // int approvedToday = auditRecordMapper.countTodayByAction("APPROVE");
        // int rejectedToday = auditRecordMapper.countTodayByAction("REJECT");

        Map<String, Object> result = new HashMap<>();
        result.put("code", 0);
        result.put("data", Map.of(
            "pending_count", 0,
            "approved_today", 0,
            "rejected_today", 0
        ));
        return result;
    }
}
