package com.example.copykamanotes.service.impl;

import com.example.copykamanotes.annotation.NeedLogin;
import com.example.copykamanotes.mapper.CollectionMapper;
import com.example.copykamanotes.mapper.CollectionNoteMapper;
import com.example.copykamanotes.mapper.NoteMapper;
import com.example.copykamanotes.model.base.ApiResponse;
import com.example.copykamanotes.model.base.EmptyVO;
import com.example.copykamanotes.model.dto.collection.CollectionQueryParams;
import com.example.copykamanotes.model.dto.collection.CreateCollectionBody;
import com.example.copykamanotes.model.dto.collection.UpdateCollectionBody;
import com.example.copykamanotes.model.entity.Collection;
import com.example.copykamanotes.model.entity.CollectionNote;
import com.example.copykamanotes.model.vo.collection.CollectionVO;
import com.example.copykamanotes.model.vo.collection.CreateCollectionVO;
import com.example.copykamanotes.scope.RequestScopeData;
import com.example.copykamanotes.service.CollectionService;
import com.example.copykamanotes.utils.ApiResponseUtils;
import lombok.RequiredArgsConstructor;
import org.springframework.beans.BeanUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.Collections;
import java.util.List;
import java.util.Set;

@Service
@RequiredArgsConstructor
public class CollectionServiceImpl implements CollectionService {

    private final RequestScopeData requestScopeData;
    private final CollectionMapper collectionMapper;
    private final CollectionNoteMapper collectionNoteMapper;
    private final NoteMapper noteMapper;

    @Override
    public ApiResponse<List<CollectionVO>> getCollection(CollectionQueryParams queryParams) {
        List<Collection> collections = collectionMapper.findByCreatorId(queryParams.getCreatorId());
        List<Integer> collectionIds = collections.stream().map(Collection::getCollectionId).toList();
        final Set<Integer> collectionNoteIdCollectionIds;

        if (queryParams.getNoteId() != null) {
            collectionNoteIdCollectionIds = collectionNoteMapper.filterCollectionIdsByNoteId(queryParams.getNoteId(), collectionIds);
        } else {
            collectionNoteIdCollectionIds = Collections.emptySet();
        }

        List<CollectionVO> collectionVOList = collections.stream().map(collection -> {
            CollectionVO collectionVO = new CollectionVO();
            BeanUtils.copyProperties(collection, collectionVO);

            if (queryParams.getNoteId() == null) return collectionVO;

            CollectionVO.NoteStatus noteStatus = new CollectionVO.NoteStatus();

            noteStatus.setIsCollected(collectionNoteIdCollectionIds.contains(collection.getCollectionId()));
            noteStatus.setNoteId(queryParams.getNoteId());
            collectionVO.setNoteStatus(noteStatus);

            return collectionVO;
        }).toList();

        return ApiResponseUtils.success("获取收藏夹列表成功", collectionVOList);
    }

    @Override
    @NeedLogin
    public ApiResponse<CreateCollectionVO> createCollection(CreateCollectionBody createCollectionBody) {
        Long creatorId = requestScopeData.getUserId();

        Collection collection = new Collection();
        BeanUtils.copyProperties(createCollectionBody, collection);
        collection.setCreatorId(creatorId);

        try {
            collectionMapper.insert(collection);
            CreateCollectionVO createCollectionVO = new CreateCollectionVO();

            createCollectionVO.setCollectionId(collection.getCollectionId());
            return ApiResponseUtils.success("创建成功", createCollectionVO);
        } catch (Exception e) {
            return ApiResponseUtils.error("创建失败");
        }
    }

    @Override
    @NeedLogin
    @Transactional
    public ApiResponse<EmptyVO> deleteCollection(Integer id) {
        Long creatorId = requestScopeData.getUserId();
        Collection collection = collectionMapper.findByIdAndCreatorId(id, creatorId);

        if (collection == null) {
            return ApiResponseUtils.error("收藏夹不存在");
        }

        try {
            collectionMapper.deleteById(id);
            collectionNoteMapper.deleteByCollectionId(id);
            return ApiResponseUtils.success("删除成功");
        } catch (Exception e) {
            return ApiResponseUtils.error("删除失败");
        }
    }

    @Override
    @NeedLogin
    @Transactional
    public ApiResponse<EmptyVO> batchModifyCollection(UpdateCollectionBody updateCollectionBody) {

        Long userId = requestScopeData.getUserId();
        Integer noteId = updateCollectionBody.getNoteId();

        UpdateCollectionBody.UpdateItem[] collections = updateCollectionBody.getCollections();

        for (UpdateCollectionBody.UpdateItem collection : collections) {
            Integer collectionId = collection.getCollectionId();
            String action = collection.getAction();

            Collection collectionEntity = collectionMapper.findByIdAndCreatorId(collectionId, userId);

            if (collectionEntity == null)
                return ApiResponseUtils.error("收藏夹不存在");

            if (action.equals("create")) {
                try {
                    if (collectionMapper.countByCreatorIdAndNoteId(userId, noteId) == 0) {
                        noteMapper.collectNote(noteId);
                    }
                    CollectionNote collectionNote = new CollectionNote();
                    collectionNote.setCollectionId(collectionId);
                    collectionNote.setNoteId(noteId);
                    collectionNoteMapper.insert(collectionNote);
                } catch (Exception e) {
                    return ApiResponseUtils.error("收藏失败");
                }
            }

            if (action.equals("delete")) {
                try {
                    collectionNoteMapper.deleteByCollectionIdAndNoteId(collectionId, noteId);
                    if (collectionMapper.countByCreatorIdAndNoteId(userId, noteId) == 0) {
                        noteMapper.unCollectNote(noteId);
                    }
                } catch (Exception e) {
                    return ApiResponseUtils.error("取消收藏失败");
                }
            }
        }

        return ApiResponseUtils.success("操作成功");

    }
}