import { Injectable, NotFoundException, Logger, ForbiddenException, BadRequestException } from '@nestjs/common';
import { InjectModel } from '@nestjs/sequelize';
import { MoodCheckin, MoodType } from './models/mood-checkin.model';
import {
  CreateMoodCheckinDto,
  UpdateMoodCheckinDto,
  RemoveMoodCheckinDto,
  MoodCheckinResponseDto,
  GetMoodHistoryQueryDto,
  MoodStatistics
} from './dto/mood-checkin.dto';
import { ResponseCode } from '../base.dto';
import * as dayjs from 'dayjs';
import { Op } from 'sequelize';
import { ActivityLogsService } from '../activity-logs/activity-logs.service';
import { ActivityActionType, ActivityEntityType } from '../activity-logs/models/activity-log.model';

@Injectable()
export class MoodCheckinsService {
  private readonly logger = new Logger(MoodCheckinsService.name);

  constructor(
    @InjectModel(MoodCheckin)
    private readonly moodCheckinModel: typeof MoodCheckin,
    private readonly activityLogsService: ActivityLogsService,
  ) { }

  async create(dto: CreateMoodCheckinDto, userId: string): Promise<MoodCheckinResponseDto> {
    const checkinDate = dto.checkinDate || dayjs().format('YYYY-MM-DD');

    // 检查当天是否已有相同心情类型的记录
    const existingRecord = await this.moodCheckinModel.findOne({
      where: {
        userId,
        moodType: dto.moodType,
        checkinDate,
        deleted: false,
      },
    });

    if (existingRecord) {
      // 如果存在，则更新现有记录
      return this.update({
        ...dto,
        id: existingRecord.id,
        checkinDate,
      }, userId);
    }

    const record = await this.moodCheckinModel.create({
      userId,
      moodType: dto.moodType,
      intensity: dto.intensity,
      description: dto.description || null,
      checkinDate,
      metadata: dto.metadata || null,
    });

    await this.activityLogsService.record({
      userId,
      entityType: ActivityEntityType.CHECKIN,
      action: ActivityActionType.CREATE,
      entityId: record.id,
      changes: record.toJSON(),
    });

    return {
      code: ResponseCode.SUCCESS,
      message: '心情打卡成功',
      data: record.toJSON()
    };
  }

  async update(dto: UpdateMoodCheckinDto, userId: string): Promise<MoodCheckinResponseDto> {
    const record = await this.moodCheckinModel.findOne({
      where: {
        id: dto.id,
        deleted: false,
      },
    });

    if (!record) {
      throw new NotFoundException('心情打卡记录不存在');
    }

    if (record.userId !== userId) {
      throw new ForbiddenException('无权操作该心情打卡记录');
    }

    const changes: Record<string, any> = {};
    if (dto.moodType !== undefined) {
      record.moodType = dto.moodType;
      changes.moodType = dto.moodType;
    }
    if (dto.intensity !== undefined) {
      record.intensity = dto.intensity;
      changes.intensity = dto.intensity;
    }
    if (dto.description !== undefined) {
      record.description = dto.description;
      changes.description = dto.description;
    }
    if (dto.checkinDate !== undefined) {
      record.checkinDate = dto.checkinDate;
      changes.checkinDate = dto.checkinDate;
    }
    if (dto.metadata !== undefined) {
      record.metadata = dto.metadata as any;
      changes.metadata = dto.metadata;
    }

    await record.save();

    await this.activityLogsService.record({
      userId: record.userId,
      entityType: ActivityEntityType.CHECKIN,
      action: ActivityActionType.UPDATE,
      entityId: record.id,
      changes,
    });

    return {
      code: ResponseCode.SUCCESS,
      message: '心情打卡更新成功',
      data: record.toJSON()
    };
  }

  async remove(dto: RemoveMoodCheckinDto, userId: string): Promise<MoodCheckinResponseDto> {
    const record = await this.moodCheckinModel.findByPk(dto.id);

    if (!record) {
      throw new NotFoundException('心情打卡记录不存在');
    }

    if (record.userId !== userId) {
      throw new ForbiddenException('无权操作该心情打卡记录');
    }

    record.deleted = true;
    await record.save();

    await this.activityLogsService.record({
      userId: record.userId,
      entityType: ActivityEntityType.CHECKIN,
      action: ActivityActionType.DELETE,
      entityId: record.id,
      changes: null,
    });

    return {
      code: ResponseCode.SUCCESS,
      message: '心情打卡删除成功',
      data: { id: dto.id }
    };
  }

  async getDaily(userId: string, date?: string): Promise<MoodCheckinResponseDto> {
    const targetDate = date || dayjs().format('YYYY-MM-DD');

    if (!dayjs(targetDate, 'YYYY-MM-DD').isValid()) {
      throw new BadRequestException('无效日期格式');
    }

    const records = await this.moodCheckinModel.findAll({
      where: {
        userId,
        checkinDate: targetDate,
        deleted: false,
      },
      order: [['createdAt', 'ASC']],
    });

    return {
      code: ResponseCode.SUCCESS,
      message: 'success',
      data: records.map(r => r.toJSON())
    };
  }

  async getHistory(userId: string, query: GetMoodHistoryQueryDto): Promise<MoodCheckinResponseDto> {
    const start = dayjs(query.startDate, 'YYYY-MM-DD');
    const end = dayjs(query.endDate, 'YYYY-MM-DD');

    if (!start.isValid() || !end.isValid() || end.isBefore(start)) {
      throw new BadRequestException('无效日期范围');
    }

    const whereCondition: any = {
      userId,
      checkinDate: {
        [Op.between]: [start.format('YYYY-MM-DD'), end.format('YYYY-MM-DD')],
      },
      deleted: false,
    };

    if (query.moodType) {
      whereCondition.moodType = query.moodType;
    }

    const records = await this.moodCheckinModel.findAll({
      where: whereCondition,
      order: [['checkinDate', 'DESC'], ['createdAt', 'DESC']],
    });

    return {
      code: ResponseCode.SUCCESS,
      message: 'success',
      data: records.map(r => r.toJSON())
    };
  }

  async getStatistics(userId: string, startDate: string, endDate: string): Promise<MoodCheckinResponseDto<MoodStatistics>> {
    const start = dayjs(startDate, 'YYYY-MM-DD');
    const end = dayjs(endDate, 'YYYY-MM-DD');

    if (!start.isValid() || !end.isValid() || end.isBefore(start)) {
      throw new BadRequestException('无效日期范围');
    }

    const records = await this.moodCheckinModel.findAll({
      where: {
        userId,
        checkinDate: {
          [Op.between]: [start.format('YYYY-MM-DD'), end.format('YYYY-MM-DD')],
        },
        deleted: false,
      },
    });

    const totalCheckins = records.length;
    const averageIntensity = totalCheckins > 0
      ? records.reduce((sum, record) => sum + record.intensity, 0) / totalCheckins
      : 0;

    const moodDistribution: Record<MoodType, number> = {
      [MoodType.HAPPY]: 0,
      [MoodType.EXCITED]: 0,
      [MoodType.THRILLED]: 0,
      [MoodType.CALM]: 0,
      [MoodType.ANXIOUS]: 0,
      [MoodType.SAD]: 0,
      [MoodType.LONELY]: 0,
      [MoodType.WRONGED]: 0,
      [MoodType.ANGRY]: 0,
      [MoodType.TIRED]: 0,
    };

    records.forEach(record => {
      moodDistribution[record.moodType]++;
    });

    const mostFrequentMood = totalCheckins > 0
      ? Object.entries(moodDistribution).reduce((a, b) =>
        moodDistribution[a[0] as MoodType] > moodDistribution[b[0] as MoodType] ? a : b
      )[0] as MoodType
      : null;

    const statistics: MoodStatistics = {
      totalCheckins,
      averageIntensity: Math.round(averageIntensity * 100) / 100,
      moodDistribution,
      mostFrequentMood,
    };

    return {
      code: ResponseCode.SUCCESS,
      message: 'success',
      data: statistics
    };
  }
}