package service

import (
	"context"
	"fmt"
	"rag/common/eino"
	"rag/consts/model"
	"rag/consts/task"
	"rag/dao"
	"rag/model/dto"
	"rag/model/entity"

	"gitea.com/red-future/common/beans"
	"github.com/cloudwego/eino/components/retriever"
	"github.com/cloudwego/eino/schema"
	"github.com/gogf/gf/v2/frame/g"
	"github.com/gogf/gf/v2/util/gconv"
	"github.com/pgvector/pgvector-go"
)

var DocumentVector = new(documentVectorService)

type documentVectorService struct{}

// Query 执行RAG查询
func (s *documentVectorService) Query(ctx context.Context, req *dto.RAGQueryReq) (*dto.RAGQueryRes, error) {

	modelInfo, err := dao.Model.Get(ctx, &dto.GetModelReq{
		ModelType: model.ModelTypeChat.Code(),
	})
	if err != nil {
		g.Log().Errorf(ctx, "获取模型失败: %v", err)
		return nil, fmt.Errorf("获取模型失败: %w", err)
	}
	if modelInfo == nil {
		g.Log().Errorf(ctx, "模型不存在: %v", model.ModelTypeChat.Code())
		return nil, fmt.Errorf("模型不存在: %w", err)
	}

	// 4. 使用向量检索器进行查询
	r, err := eino.NewPGVectorRetriever(ctx, &eino.PGVectorRetrieverConfig{
		DefaultTopK: req.TopK,
	}, model.ModelConfigTypeVectorDashScope.Code()) //TODO 后续替换成本地模型
	if err != nil {
		g.Log().Errorf(ctx, "初始化向量检索器失败: %v", err)
		return nil, fmt.Errorf("初始化向量检索器失败: %w", err)
	}

	// 5. 执行向量检索
	docs, err := r.Retrieve(ctx, req.Content, retriever.WithDSLInfo(map[string]any{
		"dataset_ids":  req.DatasetIds,
		"document_ids": req.DocumentIds,
	}))
	if err != nil {
		g.Log().Errorf(ctx, "向量检索失败: %v", err)
		return nil, fmt.Errorf("向量检索失败: %w", err)
	}

	messages := make([]*schema.Message, 0)
	err = gconv.Struct(req.History, &messages)
	if err != nil {
		g.Log().Errorf(ctx, "转换历史消息失败: %v", err)
		return nil, fmt.Errorf("转换历史消息失败: %w", err)
	}

	replyMsg, err := eino.NewChatModel(ctx, req.Content, docs, messages, modelInfo.ConfigType)
	if err != nil {
		g.Log().Errorf(ctx, "向量检索失败: %v", err)
		return nil, fmt.Errorf("向量检索失败: %w", err)
	}

	return &dto.RAGQueryRes{
		Answer: replyMsg.Content,
	}, nil
}

// Update 更新文件块
func (s *documentVectorService) Update(ctx context.Context, req *dto.UpdateDocumentVectorReq) (err error) {
	_, err = dao.DocumentVector.Update(ctx, req)
	return
}

// List 获取文件块列表
func (s *documentVectorService) List(ctx context.Context, req *dto.ListDocumentVectorReq) (res *dto.ListDocumentVectorRes, err error) {
	list, total, err := dao.DocumentVector.List(ctx, req)
	if err != nil {
		return
	}
	res = &dto.ListDocumentVectorRes{
		Total: total,
	}
	err = gconv.Struct(list, &res.List)
	return
}

func (s *documentVectorService) DocsChunkMsg(ctx context.Context, msg any) (err error) {
	var docs = make([]*schema.Document, 0)
	msgMap := gconv.Map(msg)
	if err = gconv.Structs(msgMap["data"], &docs); err != nil {
		g.Log().Error(ctx, "DocsChunkMsg err:", err)
		return
	}
	if len(docs) == 0 {
		g.Log().Error(ctx, "DocsChunkMsg err:", "msg is empty")
		return
	}
	ctx = context.WithValue(ctx, "user", &beans.User{
		TenantId: gconv.Uint64(docs[0].MetaData[entity.DocumentVectorCol.TenantId]),
		UserName: gconv.String(docs[0].MetaData[entity.DocumentVectorCol.Creator]),
	})

	documentId := gconv.Int64(docs[0].MetaData[entity.DocumentVectorCol.DocumentId])

	var docsStore = make([]*schema.Document, 0)
	var docsInsert = make([]*dto.VectorDocumentVectorMsg, 0)
	for _, doc := range docs {
		if gconv.Bool(doc.MetaData["isNew"]) {
			docsStore = append(docsStore, doc)
		} else {
			ck := new(dto.VectorDocumentVectorMsg)
			err = gconv.Struct(doc.MetaData, ck)
			ck.Content = doc.Content
			ck.VectorStatus = gconv.PtrInt8(1)
			ck.Status = gconv.PtrInt8(1)
			docsInsert = append(docsInsert, ck)
		}
	}

	if !g.IsEmpty(docsStore) {
		idx := eino.NewPGVectorIndexer(&eino.PGVectorIndexerOptions{
			BatchSize: 10,
		})
		var rows int64
		rows, err = idx.Store(ctx, docsStore, model.ModelConfigTypeVectorDashScope.Code()) //TODO 后续替换成本地模型

		if err != nil || rows == 0 {
			g.Log().Error(ctx, "DocsChunkMsg rows: , err:", rows, err)
			// 写入任务进度失败 任务类型为sql存储
			remark := " 向量存储数量: " + gconv.String(rows)
			if err != nil {
				remark = "向量存储失败: " + err.Error()
			}
			err = Task.WriteTaskProgress(ctx, &dto.WriteTaskProgressReq{
				TaskId:   documentId,
				TaskType: task.TaskTypeGenerateVector,
				Status:   task.TaskStatusFailed,
				Remark:   remark,
			})
			return
		}
	}

	if !g.IsEmpty(docsInsert) {
		// 1. 提取所有 contentHash
		contentHashs := make([]string, 0, len(docsInsert))
		for _, d := range docsInsert {
			contentHashs = append(contentHashs, d.ContentHash)
		}

		// 2. 分页查询已存在的向量（一页1000，避免大查询）
		var existVectors []*entity.DocumentVector
		for page := 1; ; page++ {
			res, total, err := dao.DocumentVector.List(ctx, &dto.ListDocumentVectorReq{
				Page:         &beans.Page{PageSize: 1000, PageNum: int64(page)},
				ContentHashs: contentHashs,
			})
			if err != nil {
				return err
			}
			if len(res) == 0 {
				break
			}
			existVectors = append(existVectors, res...)
			if len(existVectors) >= total {
				break
			}
		}

		// 3. 构建哈希 -> 向量 的映射表（O(1) 查找，性能提升巨大）
		vectorMap := make(map[string]pgvector.Vector, len(existVectors))
		for _, v := range existVectors {
			vectorMap[v.ContentHash] = v.Vector
		}

		// 4. 回填向量 + 过滤掉数据库已存在的数据（避免重复插入）
		for _, d := range docsInsert {
			// 回填已有向量
			if vec, ok := vectorMap[d.ContentHash]; ok {
				d.Vector = vec
			}
		}

		var rows int64
		rows, err = dao.DocumentVector.BatchInsert(ctx, docsInsert)

		if err != nil || rows == 0 {
			g.Log().Error(ctx, "DocsChunkMsg rows: , err:", rows, err)
			// 写入任务进度失败 任务类型为sql存储
			remark := " 向量存储数量: " + gconv.String(rows)
			if err != nil {
				remark = "向量存储失败: " + err.Error()
			}
			err = Task.WriteTaskProgress(ctx, &dto.WriteTaskProgressReq{
				TaskId:   documentId,
				TaskType: task.TaskTypeGenerateVector,
				Status:   task.TaskStatusFailed,
				Remark:   remark,
			})
			return
		}
	}

	// 写入任务进度成功 任务类型为sql存储
	err = Task.WriteTaskProgress(ctx, &dto.WriteTaskProgressReq{
		TaskId:   documentId,
		TaskType: task.TaskTypeGenerateVector,
		Status:   task.TaskStatusCompleted,
		Remark:   "向量生成完成",
	})
	return
}