package com.guo.learningprogresstracker.controller;

import com.google.protobuf.ServiceException;
import com.guo.learningprogresstracker.dto.request.EndedStudySessionRequest;
import com.guo.learningprogresstracker.dto.request.UpsertExpectationRequest;
import com.guo.learningprogresstracker.dto.response.StudySessionResponse;
import com.baomidou.mybatisplus.extension.plugins.pagination.Page;
import com.guo.learningprogresstracker.entity.CommonResult;
import com.guo.learningprogresstracker.entity.StudyExpectationsEntity;
import com.guo.learningprogresstracker.entity.StudyReportFragmentsEntity;
import com.guo.learningprogresstracker.entity.StudyReportsEntity;
import com.guo.learningprogresstracker.exception.ErrorParameterException;
import com.guo.learningprogresstracker.service.StudyExpectationsService;
import com.guo.learningprogresstracker.service.impl.StudySessionsServiceImpl;
import jakarta.validation.Valid;
import jakarta.validation.constraints.NotEmpty;
import lombok.RequiredArgsConstructor;
import org.springframework.validation.annotation.Validated;
import org.springframework.web.bind.annotation.*;

import java.util.ArrayList;
import java.time.LocalDateTime;

/**
 * 学习会话控制层
 */
@RequestMapping("/study-sessions")
@RestController
@RequiredArgsConstructor
@Validated
public class StudySessionController {

    private final StudySessionsServiceImpl studySessionsServiceImpl;

    private final StudyExpectationsService studyExpectationsService;

    /**
     * 创建/更新学习会话的学习预期
     */
    @PutMapping("/{sessionNum}/expectation")
    public CommonResult<StudyExpectationsEntity> upsertExpectation(
            @PathVariable("sessionNum") String sessionNum,
            @Valid @RequestBody UpsertExpectationRequest request) throws ErrorParameterException {
        return CommonResult.success(studyExpectationsService.upsertExpectation(sessionNum, request.getDescription()));
    }

    /**
     * 获取学习会话的学习预期
     */
    @GetMapping("/{sessionNum}/expectation")
    public CommonResult<StudyExpectationsEntity> getExpectation(
            @PathVariable("sessionNum") String sessionNum) {
        return CommonResult.success(studyExpectationsService.getBySessionNum(sessionNum));
    }

    /**
     * 通过sessionNum获取一个【学习会话】
     */
    @GetMapping("/{sessionNum}")
    public CommonResult<StudySessionResponse> getStudySessionBySessionNum(@NotEmpty(message = "sessionNum不可为空") @PathVariable String sessionNum) throws ErrorParameterException {
        // 通过 service 层获取，包含归属校验
        StudySessionResponse response = studySessionsServiceImpl.getStudySessionBySessionNum(sessionNum);
        return CommonResult.success(response);
    }

    /**
     * 开始一个【学习会话】
     */
    @PostMapping("/{sessionNum}/study-sessions/continue")
    public CommonResult<Void> startStudySession(@PathVariable("sessionNum") String sessionNum) throws ErrorParameterException, ServiceException {
        studySessionsServiceImpl.continueStudySession(sessionNum);
        return CommonResult.success();
    }

    /**
     * 暂停一个【学习会话】
     */
    @PostMapping("/{sessionNum}/study-sessions/pause")
    public CommonResult<Void> pauseStudySession(@PathVariable("sessionNum") String sessionNum,
                                                @RequestParam(value = "endTime", required = false) LocalDateTime endTime)
            throws ErrorParameterException, ServiceException {
        studySessionsServiceImpl.pauseStudySession(sessionNum, endTime);
        return CommonResult.success();
    }

    /**
     * 结束一个【学习会话】
     */
    @PostMapping("/{sessionNum}/study-sessions/ended")
    public CommonResult<Void> endedStudySession(@PathVariable("sessionNum") String sessionNum,
                                                @Valid @RequestBody EndedStudySessionRequest request) throws ErrorParameterException {
        String message = studySessionsServiceImpl.endedStudySession(sessionNum, request.getContent());
        return message != null ? CommonResult.success(message) : CommonResult.success();
    }

    /**
     * 获取【学习会话】所有的学习残片数据，以列表返回
     */
    @GetMapping("/{sessionNum}/all-fragments")
    public CommonResult<ArrayList<String>> getAllFragments(@PathVariable("sessionNum") String sessionNum) throws ErrorParameterException {
        ArrayList<String> allFragments = studySessionsServiceImpl.getAllFragments(sessionNum);
        return CommonResult.success(allFragments);

    }

    /**
     * 生成学习报告草稿：AI 聚合残片（不可用时降级为拼接），返回给前端作为编辑起点
     */
    @GetMapping("/{sessionNum}/report-draft")
    public CommonResult<String> getReportDraft(@PathVariable("sessionNum") String sessionNum) throws ErrorParameterException {
        return CommonResult.success("请求成功", studySessionsServiceImpl.generateReportDraft(sessionNum));
    }

    /** 分页查询任务的残片历史 */
    @GetMapping("/tasks/{taskNum}/fragments")
    public CommonResult<Page<StudyReportFragmentsEntity>> getTaskFragments(
            @PathVariable String taskNum,
            @RequestParam(defaultValue = "1") int page,
            @RequestParam(defaultValue = "10") int size,
            @RequestParam(required = false) String keyword) {
        return CommonResult.success(studySessionsServiceImpl.getTaskFragments(taskNum, page, size, keyword));
    }

    /** 分页查询任务的报告历史 */
    @GetMapping("/tasks/{taskNum}/reports")
    public CommonResult<Page<StudyReportsEntity>> getTaskReports(
            @PathVariable String taskNum,
            @RequestParam(defaultValue = "1") int page,
            @RequestParam(defaultValue = "10") int size,
            @RequestParam(required = false) String keyword) {
        return CommonResult.success(studySessionsServiceImpl.getTaskReports(taskNum, page, size, keyword));
    }

    /** 查询当前是否有活跃会话（用于跨页面恢复 + 阻止多任务） */
    @GetMapping("/active")
    public CommonResult<StudySessionResponse> getActiveSession(
            @RequestParam(required = false) String excludeTaskNum) {
        return CommonResult.success(studySessionsServiceImpl.getActiveSession(excludeTaskNum));
    }
}