package app

import (
	"encoding/json"
	"errors"
	"regexp"
	"strings"

	"git.echol.cn/loser/st/server/global"
	"git.echol.cn/loser/st/server/model/app"
	"git.echol.cn/loser/st/server/model/app/request"
	"git.echol.cn/loser/st/server/model/app/response"
	"go.uber.org/zap"
	"gorm.io/datatypes"
	"gorm.io/gorm"
)

type RegexScriptService struct{}

// CreateRegexScript 创建正则脚本
func (s *RegexScriptService) CreateRegexScript(userID uint, req *request.CreateRegexScriptRequest) (*response.RegexScriptResponse, error) {
	trimStringsJSON, _ := json.Marshal(req.TrimStrings)

	script := &app.RegexScript{
		UserID:          userID,
		Name:            req.Name,
		FindRegex:       req.FindRegex,
		ReplaceWith:     req.ReplaceWith,
		TrimStrings:     datatypes.JSON(trimStringsJSON),
		Placement:       req.Placement,
		Disabled:        req.Disabled,
		MarkdownOnly:    req.MarkdownOnly,
		RunOnEdit:       req.RunOnEdit,
		PromptOnly:      req.PromptOnly,
		SubstituteRegex: req.SubstituteRegex,
		MinDepth:        req.MinDepth,
		MaxDepth:        req.MaxDepth,
		Scope:           req.Scope,
		OwnerCharID:     req.OwnerCharID,
		OwnerPresetID:   req.OwnerPresetID,
		Order:           req.Order,
	}

	if err := global.GVA_DB.Create(script).Error; err != nil {
		global.GVA_LOG.Error("创建正则脚本失败", zap.Error(err))
		return nil, err
	}

	resp := response.ToRegexScriptResponse(script)
	return &resp, nil
}

// GetRegexScriptList 获取正则脚本列表
func (s *RegexScriptService) GetRegexScriptList(userID uint, req *request.GetRegexScriptListRequest) ([]response.RegexScriptResponse, int64, error) {
	var scripts []app.RegexScript
	var total int64

	db := global.GVA_DB.Model(&app.RegexScript{}).Where("user_id = ?", userID)

	if req.Keyword != "" {
		db = db.Where("name LIKE ?", "%"+req.Keyword+"%")
	}

	if req.Scope != nil {
		db = db.Where("scope = ?", *req.Scope)
	}

	if err := db.Count(&total).Error; err != nil {
		return nil, 0, err
	}

	offset := (req.Page - 1) * req.PageSize
	if err := db.Order("\"order\" ASC, created_at DESC").Offset(offset).Limit(req.PageSize).Find(&scripts).Error; err != nil {
		global.GVA_LOG.Error("获取正则脚本列表失败", zap.Error(err))
		return nil, 0, err
	}

	var list []response.RegexScriptResponse
	for i := range scripts {
		list = append(list, response.ToRegexScriptResponse(&scripts[i]))
	}
	return list, total, nil
}

// GetRegexScriptByID 获取正则脚本详情
func (s *RegexScriptService) GetRegexScriptByID(userID uint, id uint) (*response.RegexScriptResponse, error) {
	var script app.RegexScript
	if err := global.GVA_DB.Where("id = ? AND user_id = ?", id, userID).First(&script).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, errors.New("正则脚本不存在或无权访问")
		}
		return nil, err
	}
	resp := response.ToRegexScriptResponse(&script)
	return &resp, nil
}

// UpdateRegexScript 更新正则脚本
func (s *RegexScriptService) UpdateRegexScript(userID uint, id uint, req *request.UpdateRegexScriptRequest) error {
	var script app.RegexScript
	if err := global.GVA_DB.Where("id = ? AND user_id = ?", id, userID).First(&script).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return errors.New("正则脚本不存在或无权修改")
		}
		return err
	}

	updates := make(map[string]interface{})
	if req.Name != nil {
		updates["name"] = *req.Name
	}
	if req.FindRegex != nil {
		updates["find_regex"] = *req.FindRegex
	}
	if req.ReplaceWith != nil {
		updates["replace_with"] = *req.ReplaceWith
	}
	if req.TrimStrings != nil {
		trimStringsJSON, _ := json.Marshal(req.TrimStrings)
		updates["trim_strings"] = datatypes.JSON(trimStringsJSON)
	}
	if req.Placement != nil {
		updates["placement"] = *req.Placement
	}
	if req.Disabled != nil {
		updates["disabled"] = *req.Disabled
	}
	if req.MarkdownOnly != nil {
		updates["markdown_only"] = *req.MarkdownOnly
	}
	if req.RunOnEdit != nil {
		updates["run_on_edit"] = *req.RunOnEdit
	}
	if req.PromptOnly != nil {
		updates["prompt_only"] = *req.PromptOnly
	}
	if req.SubstituteRegex != nil {
		updates["substitute_regex"] = *req.SubstituteRegex
	}
	if req.MinDepth != nil {
		updates["min_depth"] = req.MinDepth
	}
	if req.MaxDepth != nil {
		updates["max_depth"] = req.MaxDepth
	}
	if req.Scope != nil {
		updates["scope"] = *req.Scope
	}
	if req.OwnerCharID != nil {
		updates["owner_char_id"] = req.OwnerCharID
	}
	if req.OwnerPresetID != nil {
		updates["owner_preset_id"] = req.OwnerPresetID
	}
	if req.Order != nil {
		updates["order"] = *req.Order
	}

	return global.GVA_DB.Model(&script).Updates(updates).Error
}

// DeleteRegexScript 删除正则脚本
func (s *RegexScriptService) DeleteRegexScript(userID uint, id uint) error {
	result := global.GVA_DB.Where("id = ? AND user_id = ?", id, userID).Delete(&app.RegexScript{})
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected == 0 {
		return errors.New("正则脚本不存在或无权删除")
	}
	return nil
}

// TestRegexScript 测试正则脚本
func (s *RegexScriptService) TestRegexScript(userID uint, id uint, testString string) (*response.TestRegexScriptResponse, error) {
	var script app.RegexScript
	if err := global.GVA_DB.Where("id = ? AND user_id = ?", id, userID).First(&script).Error; err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			return nil, errors.New("正则脚本不存在或无权访问")
		}
		return nil, err
	}

	result, err := s.ExecuteScript(&script, testString, "", "")
	if err != nil {
		return &response.TestRegexScriptResponse{
			Original: testString,
			Result:   testString,
			Success:  false,
			Error:    err.Error(),
		}, nil
	}

	return &response.TestRegexScriptResponse{
		Original: testString,
		Result:   result,
		Success:  true,
	}, nil
}

// ExecuteScript 执行正则脚本
func (s *RegexScriptService) ExecuteScript(script *app.RegexScript, text string, userName string, charName string) (string, error) {
	if script.Disabled {
		return text, nil
	}

	result := text

	// 1. 宏替换
	if script.SubstituteRegex {
		result = s.substituteMacros(result, userName, charName)
	}

	// 2. 正则替换
	if script.FindRegex != "" {
		re, err := regexp.Compile(script.FindRegex)
		if err != nil {
			global.GVA_LOG.Warn("正则表达式编译失败", zap.String("pattern", script.FindRegex), zap.Error(err))
			return text, err
		}
		result = re.ReplaceAllString(result, script.ReplaceWith)
	}

	// 3. 修剪字符串
	if len(script.TrimStrings) > 0 {
		var trimStrings []string
		json.Unmarshal(script.TrimStrings, &trimStrings)
		for _, trimStr := range trimStrings {
			result = strings.ReplaceAll(result, trimStr, "")
		}
	}

	return result, nil
}

// substituteMacros 替换宏变量
func (s *RegexScriptService) substituteMacros(text string, userName string, charName string) string {
	result := text
	if userName != "" {
		result = strings.ReplaceAll(result, "{{user}}", userName)
		result = strings.ReplaceAll(result, "{{User}}", userName)
	}
	if charName != "" {
		result = strings.ReplaceAll(result, "{{char}}", charName)
		result = strings.ReplaceAll(result, "{{Char}}", charName)
	}
	return result
}

// GetScriptsForPlacement 获取指定阶段的脚本
func (s *RegexScriptService) GetScriptsForPlacement(userID uint, placement int, charID *uint, presetID *uint) ([]app.RegexScript, error) {
	var scripts []app.RegexScript

	db := global.GVA_DB.Where("user_id = ? AND placement = ? AND disabled = ?", userID, placement, false)

	// 作用域过滤：全局(0) 或 角色(1) 或 预设(2)
	scopeCondition := "scope = 0" // 全局
	if charID != nil {
		scopeCondition += " OR (scope = 1 AND owner_char_id = " + string(rune(*charID)) + ")"
	}
	if presetID != nil {
		scopeCondition += " OR (scope = 2 AND owner_preset_id = " + string(rune(*presetID)) + ")"
	}
	db = db.Where(scopeCondition)

	if err := db.Order("\"order\" ASC").Find(&scripts).Error; err != nil {
		return nil, err
	}

	return scripts, nil
}

// ExecuteScripts 批量执行脚本
func (s *RegexScriptService) ExecuteScripts(scripts []app.RegexScript, text string, userName string, charName string) string {
	result := text
	for _, script := range scripts {
		executed, err := s.ExecuteScript(&script, result, userName, charName)
		if err != nil {
			global.GVA_LOG.Warn("执行正则脚本失败", zap.String("name", script.Name), zap.Error(err))
			continue
		}
		result = executed
	}
	return result
}