package service

import (
	"encoding/json"
	"strings"
	"time"

	"x-agents/server/internal/repository"

	"x-agents/server/internal/model"

	"github.com/google/uuid"
)

// MemoryService 记忆服务
type MemoryService struct {
	agentRepo *repository.AgentRepository
}

// NewMemoryService 创建记忆服务
func NewMemoryService(agentRepo *repository.AgentRepository) *MemoryService {
	return &MemoryService{
		agentRepo: agentRepo,
	}
}

// CreateMemory 创建记忆
func (s *MemoryService) CreateMemory(agentID, userID, content, memoryType, category, tags, keywords string, importance int, isPinned bool) (*model.AgentMemory, error) {
	memory := &model.AgentMemory{
		ID:          uuid.New().String(),
		AgentID:     agentID,
		UserID:      userID,
		Content:     content,
		MemoryType:  memoryType,
		Category:    category,
		Tags:        tags,
		Keywords:    keywords,
		Importance:  importance,
		IsPinned:    isPinned,
		CreatedAt:   time.Now(),
		UpdatedAt:   time.Now(),
	}

	// 如果没有提供关键词，自动从内容中提取
	if keywords == "" && content != "" {
		memory.Keywords = extractKeywords(content)
	}

	err := s.agentRepo.CreateMemory(memory)
	if err != nil {
		return nil, err
	}

	return memory, nil
}

// GetMemories 获取记忆列表
func (s *MemoryService) GetMemories(agentID, userID, category, memoryType string, limit, offset int) ([]model.AgentMemory, int64, error) {
	return s.agentRepo.FindMemories(agentID, userID, category, memoryType, limit, offset)
}

// SearchMemories 搜索记忆
func (s *MemoryService) SearchMemories(agentID, userID, keyword, tags, category, memoryType string, minScore, limit, offset int) ([]model.AgentMemory, int64, error) {
	// 如果有关键词搜索，优先使用模糊匹配
	if keyword != "" {
		return s.agentRepo.SearchMemories(agentID, userID, keyword, tags, category, memoryType, minScore, limit, offset)
	}
	// 否则使用过滤条件查询
	return s.agentRepo.FindMemories(agentID, userID, category, memoryType, limit, offset)
}

// GetMemoryByID 获取记忆详情
func (s *MemoryService) GetMemoryByID(memoryID string) (*model.AgentMemory, error) {
	return s.agentRepo.FindMemoryByID(memoryID)
}

// UpdateMemory 更新记忆
func (s *MemoryService) UpdateMemory(memoryID, content, memoryType, category, tags, keywords string, importance int, isPinned *bool) (*model.AgentMemory, error) {
	memory, err := s.agentRepo.FindMemoryByID(memoryID)
	if err != nil {
		return nil, err
	}

	if content != "" {
		memory.Content = content
	}
	if memoryType != "" {
		memory.MemoryType = memoryType
	}
	if category != "" {
		memory.Category = category
	}
	if tags != "" {
		memory.Tags = tags
	}
	if keywords != "" {
		memory.Keywords = keywords
	}
	if importance > 0 {
		memory.Importance = importance
	}
	if isPinned != nil {
		memory.IsPinned = *isPinned
	}
	memory.UpdatedAt = time.Now()

	err = s.agentRepo.UpdateMemory(memory)
	if err != nil {
		return nil, err
	}

	return memory, nil
}

// DeleteMemory 删除记忆
func (s *MemoryService) DeleteMemory(memoryID string) error {
	return s.agentRepo.DeleteMemory(memoryID)
}

// ExportMemories 导出记忆
func (s *MemoryService) ExportMemories(agentID, userID, format string) (interface{}, error) {
	memories, _, err := s.agentRepo.FindMemories(agentID, userID, "", "", 0, 0)
	if err != nil {
		return nil, err
	}

	if format == "csv" {
		// 生成CSV格式
		var sb strings.Builder
		sb.WriteString("id,agent_id,content,memory_type,category,tags,keywords,importance,is_pinned,created_at\n")
		for _, m := range memories {
			sb.WriteString(m.ID + ",")
			sb.WriteString(m.AgentID + ",")
			sb.WriteString("\"" + strings.ReplaceAll(m.Content, "\"", "\"\"") + "\",")
			sb.WriteString(m.MemoryType + ",")
			sb.WriteString(m.Category + ",")
			sb.WriteString(m.Tags + ",")
			sb.WriteString(m.Keywords + ",")
			sb.WriteString(string(rune(m.Importance+'0')) + ",")
			if m.IsPinned {
				sb.WriteString("true")
			} else {
				sb.WriteString("false")
			}
			sb.WriteString("," + m.CreatedAt.Format(time.RFC3339) + "\n")
		}
		return sb.String(), nil
	}

	// 默认JSON格式
	return memories, nil
}

// ImportMemories 导入记忆
func (s *MemoryService) ImportMemories(agentID, userID string, items []model.ImportItem) (int, error) {
	count := 0
	for _, item := range items {
		memoryType := item.MemoryType
		if memoryType == "" {
			memoryType = "conversation"
		}
		importance := item.Importance
		if importance == 0 {
			importance = 5
		}
		keywords := item.Keywords
		if keywords == "" && item.Content != "" {
			keywords = extractKeywords(item.Content)
		}

		memory := &model.AgentMemory{
			ID:          uuid.New().String(),
			AgentID:     agentID,
			UserID:      userID,
			Content:     item.Content,
			MemoryType:  memoryType,
			Category:    item.Category,
			Tags:        item.Tags,
			Keywords:    keywords,
			Importance:  importance,
			IsPinned:    false,
			CreatedAt:   time.Now(),
			UpdatedAt:   time.Now(),
		}

		err := s.agentRepo.CreateMemory(memory)
		if err != nil {
			continue
		}
		count++
	}
	return count, nil
}

// GetMemoryCategories 获取记忆分类列表
func (s *MemoryService) GetMemoryCategories(agentID, userID string) ([]string, error) {
	return s.agentRepo.FindMemoryCategories(agentID, userID)
}

// GetMemoryTags 获取记忆标签列表
func (s *MemoryService) GetMemoryTags(agentID, userID string) ([]string, error) {
	// 从所有记忆中的 tags 字段提取所有标签
	memories, _, err := s.agentRepo.FindMemories(agentID, userID, "", "", 0, 0)
	if err != nil {
		return nil, err
	}

	tagSet := make(map[string]bool)
	for _, m := range memories {
		if m.Tags != "" {
			var tags []string
			if err := json.Unmarshal([]byte(m.Tags), &tags); err == nil {
				for _, tag := range tags {
					if tag != "" {
						tagSet[tag] = true
					}
				}
			}
		}
	}

	tags := make([]string, 0, len(tagSet))
	for tag := range tagSet {
		tags = append(tags, tag)
	}
	return tags, nil
}

// extractKeywords 从内容中提取关键词
func extractKeywords(content string) string {
	// 简单提取：取内容的前50个字符作为关键词演示
	// 实际生产中可使用分词库如 gojieba
	if len(content) <= 50 {
		return content
	}
	return content[:50]
}