package handler

import (
	"encoding/json"
	"fmt"
	"net/http"
	"time"

	"soul-api/internal/database"
	"soul-api/internal/model"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

const defaultFreeMatchLimit = 3

const completeProfileSQL = "((phone IS NOT NULL AND phone != '') AND (nickname IS NOT NULL AND nickname != '' AND nickname != '微信用户') AND (avatar IS NOT NULL AND avatar != ''))"

// MatchQuota 匹配次数配额（纯计算：订单 + match_records）
type MatchQuota struct {
	PurchasedTotal   int64 `json:"purchasedTotal"`
	PurchasedUsed    int64 `json:"purchasedUsed"`
	MatchesUsedToday int64 `json:"matchesUsedToday"`
	FreeRemainToday  int64 `json:"freeRemainToday"`
	PurchasedRemain  int64 `json:"purchasedRemain"`
	RemainToday      int64 `json:"remainToday"` // 今日剩余可匹配次数
}

func getFreeMatchLimit(db *gorm.DB) int {
	var cfg model.SystemConfig
	if err := db.Where("config_key = ?", "match_config").First(&cfg).Error; err != nil {
		return defaultFreeMatchLimit
	}
	var config map[string]interface{}
	if err := json.Unmarshal(cfg.ConfigValue, &config); err != nil {
		return defaultFreeMatchLimit
	}
	if v, ok := config["freeMatchLimit"].(float64); ok && v > 0 {
		return int(v)
	}
	return defaultFreeMatchLimit
}

// GetMatchQuota 根据订单和 match_records 纯计算用户匹配配额
func GetMatchQuota(db *gorm.DB, userID string, freeLimit int) MatchQuota {
	if freeLimit <= 0 {
		freeLimit = defaultFreeMatchLimit
	}
	var purchasedTotal int64
	db.Model(&model.Order{}).Where("user_id = ? AND product_type = ? AND status = ?", userID, "match", "paid").Count(&purchasedTotal)
	var matchesToday int64
	db.Model(&model.MatchRecord{}).Where("user_id = ? AND created_at >= CURDATE()", userID).Count(&matchesToday)
	// 历史每日超出免费部分之和 = 已消耗的购买次数
	var purchasedUsed int64
	db.Raw(`
		SELECT COALESCE(SUM(cnt - ?), 0) FROM (
			SELECT DATE(created_at) AS d, COUNT(*) AS cnt
			FROM match_records WHERE user_id = ?
			GROUP BY DATE(created_at)
			HAVING cnt > ?
		) t
	`, freeLimit, userID, freeLimit).Scan(&purchasedUsed)
	freeUsed := matchesToday
	if freeUsed > int64(freeLimit) {
		freeUsed = int64(freeLimit)
	}
	freeRemain := int64(freeLimit) - freeUsed
	if freeRemain < 0 {
		freeRemain = 0
	}
	purchasedRemain := purchasedTotal - purchasedUsed
	if purchasedRemain < 0 {
		purchasedRemain = 0
	}
	remainToday := freeRemain + purchasedRemain
	return MatchQuota{
		PurchasedTotal:   purchasedTotal,
		PurchasedUsed:    purchasedUsed,
		MatchesUsedToday: matchesToday,
		FreeRemainToday:  freeRemain,
		PurchasedRemain:  purchasedRemain,
		RemainToday:      remainToday,
	}
}

var defaultMatchTypes = []gin.H{
	gin.H{"id": "partner", "label": "找伙伴", "matchLabel": "找伙伴", "icon": "⭐", "matchFromDB": true, "showJoinAfterMatch": false, "price": 1, "enabled": true},
	gin.H{"id": "investor", "label": "资源对接", "matchLabel": "资源对接", "icon": "👥", "matchFromDB": false, "showJoinAfterMatch": true, "price": 1, "enabled": true},
	gin.H{"id": "mentor", "label": "导师顾问", "matchLabel": "导师顾问", "icon": "❤️", "matchFromDB": false, "showJoinAfterMatch": true, "price": 1, "enabled": true},
	gin.H{"id": "team", "label": "团队招募", "matchLabel": "加入项目", "icon": "🎮", "matchFromDB": false, "showJoinAfterMatch": true, "price": 1, "enabled": true},
}

// MatchConfigGet GET /api/match/config
func MatchConfigGet(c *gin.Context) {
	db := database.DB()
	var cfg model.SystemConfig
	if err := db.Where("config_key = ?", "match_config").First(&cfg).Error; err != nil {
		c.JSON(http.StatusOK, gin.H{
			"success": true,
			"data": gin.H{
				"matchTypes":     defaultMatchTypes,
				"freeMatchLimit": 3,
				"matchPrice":     1,
				"settings":       gin.H{"enableFreeMatches": true, "enablePaidMatches": true, "maxMatchesPerDay": 10},
			},
			"source": "default",
		})
		return
	}
	var config map[string]interface{}
	_ = json.Unmarshal(cfg.ConfigValue, &config)
	matchTypes := defaultMatchTypes
	if v, ok := config["matchTypes"].([]interface{}); ok && len(v) > 0 {
		matchTypes = make([]gin.H, 0, len(v))
		for _, t := range v {
			if m, ok := t.(map[string]interface{}); ok {
				enabled := true
				if e, ok := m["enabled"].(bool); ok && !e {
					enabled = false
				}
				if enabled {
					matchTypes = append(matchTypes, gin.H(m))
				}
			}
		}
		if len(matchTypes) == 0 {
			matchTypes = defaultMatchTypes
		}
	}
	freeMatchLimit := 3
	if v, ok := config["freeMatchLimit"].(float64); ok {
		freeMatchLimit = int(v)
	}
	matchPrice := 1
	if v, ok := config["matchPrice"].(float64); ok {
		matchPrice = int(v)
	}
	settings := gin.H{"enableFreeMatches": true, "enablePaidMatches": true, "maxMatchesPerDay": 10}
	if s, ok := config["settings"].(map[string]interface{}); ok {
		for k, v := range s {
			settings[k] = v
		}
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "data": gin.H{
		"matchTypes": matchTypes, "freeMatchLimit": freeMatchLimit, "matchPrice": matchPrice, "settings": settings,
	}, "source": "database"})
}

// MatchConfigPost POST /api/match/config
func MatchConfigPost(c *gin.Context) {
	c.JSON(http.StatusOK, gin.H{"success": true})
}

// MatchUsers POST /api/match/users
func MatchUsers(c *gin.Context) {
	var body struct {
		UserID    string `json:"userId" binding:"required"`
		MatchType string `json:"matchType"`
		Phone     string `json:"phone"`
		WechatID  string `json:"wechatId"`
	}
	if err := c.ShouldBindJSON(&body); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"success": false, "message": "缺少用户ID"})
		return
	}
	db := database.DB()
	// 全书用户无限制，否则校验今日剩余次数
	var user model.User
	skipQuota := false
	if err := db.Where("id = ?", body.UserID).First(&user).Error; err == nil {
		skipQuota = user.HasFullBook != nil && *user.HasFullBook
	}
	if !skipQuota {
		freeLimit := getFreeMatchLimit(db)
		quota := GetMatchQuota(db, body.UserID, freeLimit)
		if quota.RemainToday <= 0 {
			c.JSON(http.StatusOK, gin.H{
				"success": false,
				"message": "今日匹配次数已用完，请购买更多次数",
				"code":    "QUOTA_EXCEEDED",
			})
			return
		}
	}
	// 读取 poolSettings 配置决定匹配范围
	var cfg model.SystemConfig
	poolSources := []string{"vip"}
	requirePhone := true
	requireNickname := false
	requireAvatar := false
	requireBusiness := false
	if err := db.Where("config_key = ?", "match_config").First(&cfg).Error; err == nil {
		var cfgMap map[string]interface{}
		if json.Unmarshal(cfg.ConfigValue, &cfgMap) == nil {
			if ps, ok := cfgMap["poolSettings"].(map[string]interface{}); ok {
				if arr, ok := ps["poolSource"].([]interface{}); ok && len(arr) > 0 {
					poolSources = make([]string, 0, len(arr))
					for _, v := range arr {
						if s, ok := v.(string); ok {
							poolSources = append(poolSources, s)
						}
					}
				} else if v, ok := ps["poolSource"].(string); ok {
					poolSources = []string{v}
				}
				if v, ok := ps["requirePhone"].(bool); ok {
					requirePhone = v
				}
				if v, ok := ps["requireNickname"].(bool); ok {
					requireNickname = v
				}
				if v, ok := ps["requireAvatar"].(bool); ok {
					requireAvatar = v
				}
				if v, ok := ps["requireBusiness"].(bool); ok {
					requireBusiness = v
				}
			}
		}
	}
	hasSource := func(s string) bool {
		for _, v := range poolSources {
			if v == s {
				return true
			}
		}
		return false
	}

	// 排除当天已匹配过的用户
	var todayMatchedIDs []string
	db.Model(&model.MatchRecord{}).Where("user_id = ? AND created_at >= CURDATE()", body.UserID).
		Pluck("matched_user_id", &todayMatchedIDs)

	var users []model.User
	q := db.Where("id != ?", body.UserID)
	if len(todayMatchedIDs) > 0 {
		q = q.Where("id NOT IN ?", todayMatchedIDs)
	}
	// 按池子来源筛选（多选取并集）
	if hasSource("all") {
		q = q.Where("((wechat_id IS NOT NULL AND wechat_id != '') OR (phone IS NOT NULL AND phone != ''))")
	} else {
		var orConds []string
		if hasSource("vip") {
			orConds = append(orConds, "(is_vip = 1 AND vip_expire_date > NOW())")
		}
		if hasSource("complete") {
			orConds = append(orConds, completeProfileSQL)
		}
		if len(orConds) > 0 {
			combined := "(" + orConds[0]
			for i := 1; i < len(orConds); i++ {
				combined += " OR " + orConds[i]
			}
			combined += ")"
			q = q.Where(combined)
		} else {
			q = q.Where("is_vip = 1 AND vip_expire_date > NOW()")
		}
	}
	// partner 类型强制 VIP
	if body.MatchType == "partner" && !hasSource("vip") && !hasSource("all") {
		q = q.Where("is_vip = 1 AND vip_expire_date > NOW()")
	}
	// 按完善程度筛选
	if requirePhone {
		q = q.Where("phone IS NOT NULL AND phone != ''")
	}
	if requireNickname {
		q = q.Where("nickname IS NOT NULL AND nickname != ''")
	}
	if requireAvatar {
		q = q.Where("avatar IS NOT NULL AND avatar != ''")
	}
	if requireBusiness {
		q = q.Where("(help_offer IS NOT NULL AND help_offer != '') OR (help_need IS NOT NULL AND help_need != '')")
	}
	if err := q.Order("created_at DESC").Limit(20).Find(&users).Error; err != nil || len(users) == 0 {
		c.JSON(http.StatusOK, gin.H{"success": false, "message": "暂无匹配用户", "data": nil, "code": "NO_USERS"})
		return
	}
	// 随机选一个
	idx := 0
	if len(users) > 1 {
		idx = int(users[0].CreatedAt.Unix() % int64(len(users)))
	}
	r := users[idx]
	nickname := "微信用户"
	if r.Nickname != nil {
		nickname = *r.Nickname
	}
	avatar := ""
	if r.Avatar != nil {
		avatar = *r.Avatar
	}
	wechat := ""
	if r.WechatID != nil {
		wechat = *r.WechatID
	}
	phone := ""
	if r.Phone != nil {
		phone = *r.Phone
	}
	intro := "来自Soul创业派对的伙伴"
	matchLabels := map[string]string{"partner": "找伙伴", "investor": "资源对接", "mentor": "导师顾问", "team": "团队招募"}
	tag := matchLabels[body.MatchType]
	if tag == "" {
		tag = "找伙伴"
	}
	// 写入匹配记录（含发起者的 phone/wechat_id 便于后续联系）
	rec := model.MatchRecord{
		ID:            fmt.Sprintf("mr_%d", time.Now().UnixNano()),
		UserID:        body.UserID,
		MatchedUserID: r.ID,
		MatchType:     body.MatchType,
	}
	if body.MatchType == "" {
		rec.MatchType = "partner"
	}
	if body.Phone != "" {
		rec.Phone = &body.Phone
	}
	if body.WechatID != "" {
		rec.WechatID = &body.WechatID
	}
	if err := db.Create(&rec).Error; err != nil {
		fmt.Printf("[MatchUsers] 写入 match_records 失败: %v\n", err)
	}
	c.JSON(http.StatusOK, gin.H{
		"success": true,
		"data": gin.H{
			"id": r.ID, "nickname": nickname, "avatar": avatar, "wechat": wechat, "phone": phone,
			"introduction": intro, "tags": []string{"创业者", tag},
			"matchScore": 80 + (r.CreatedAt.Unix() % 20),
			"commonInterests": []gin.H{
				gin.H{"icon": "📚", "text": "都在读《创业派对》"},
				gin.H{"icon": "💼", "text": "对创业感兴趣"},
				gin.H{"icon": "🎯", "text": "相似的发展方向"},
			},
		},
		"totalUsers": len(users),
	})
}