package handler

import (
	"encoding/json"
	"errors"
	"net/http"
	"strings"

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

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

const mbtiAvatarsConfigKey = "mbti_avatars"
const mbtiAvatarsDescription = "MBTI 16型人格头像映射"

var allMbtiTypes = []string{
	"INTJ", "INTP", "ENTJ", "ENTP",
	"INFJ", "INFP", "ENFJ", "ENFP",
	"ISTJ", "ISFJ", "ESTJ", "ESFJ",
	"ISTP", "ISFP", "ESTP", "ESFP",
}

// buildDefaultMbtiAvatarMap returns the default PNG avatar mapping for all 16 types.
func buildDefaultMbtiAvatarMap() map[string]string {
	m := make(map[string]string, 16)
	for _, t := range allMbtiTypes {
		m[t] = "/static/mbti-avatars-png-male/" + t + ".png"
	}
	return m
}

// absolutizeMbtiAvatarMap 将 /static、/uploads 等相对路径转为当前 API 公网可访问的绝对 URL，
// 避免管理端页面 <img src="/static/..."> 请求到前端 dev 端口、以及小程序端拼接 baseUrl 异常时不显示。
func absolutizeMbtiAvatarMap(c *gin.Context, m map[string]string) map[string]string {
	if m == nil {
		return nil
	}
	out := make(map[string]string, len(m))
	for k, v := range m {
		out[k] = resolveAvatarURLWithRequest(c, strings.TrimSpace(v))
	}
	return out
}

// AdminMbtiAvatarsGet GET /api/admin/mbti-avatars 读取 MBTI 头像映射（system_config.mbti_avatars）
// 无配置时自动填充 PNG 默认路径并持久化。
func AdminMbtiAvatarsGet(c *gin.Context) {
	db := database.DB()
	var row model.SystemConfig
	err := db.Where("config_key = ?", mbtiAvatarsConfigKey).First(&row).Error
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			defaults := buildDefaultMbtiAvatarMap()
			valBytes, _ := json.Marshal(defaults)
			desc := mbtiAvatarsDescription
			newRow := model.SystemConfig{
				ConfigKey:   mbtiAvatarsConfigKey,
				ConfigValue: valBytes,
				Description: &desc,
			}
			db.Create(&newRow)
			_mbtiAvatarCacheTs = 0
			c.JSON(http.StatusOK, gin.H{"success": true, "avatars": absolutizeMbtiAvatarMap(c, defaults)})
			return
		}
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "读取配置失败: " + err.Error()})
		return
	}
	out := make(map[string]string)
	if len(row.ConfigValue) > 0 {
		if uerr := json.Unmarshal(row.ConfigValue, &out); uerr != nil {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "配置 JSON 无效: " + uerr.Error()})
			return
		}
	}
	if len(out) == 0 {
		out = buildDefaultMbtiAvatarMap()
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "avatars": absolutizeMbtiAvatarMap(c, out)})
}

// AdminMbtiAvatarsPost POST /api/admin/mbti-avatars 保存 MBTI 头像映射（upsert）
func AdminMbtiAvatarsPost(c *gin.Context) {
	var body struct {
		Avatars map[string]string `json:"avatars"`
	}
	if err := c.ShouldBindJSON(&body); err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "请求体无效"})
		return
	}
	avatars := body.Avatars
	if avatars == nil {
		avatars = map[string]string{}
	}
	valBytes, err := json.Marshal(avatars)
	if err != nil {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "序列化失败: " + err.Error()})
		return
	}
	db := database.DB()
	desc := mbtiAvatarsDescription
	var row model.SystemConfig
	err = db.Where("config_key = ?", mbtiAvatarsConfigKey).First(&row).Error
	if err != nil {
		if errors.Is(err, gorm.ErrRecordNotFound) {
			row = model.SystemConfig{
				ConfigKey:   mbtiAvatarsConfigKey,
				ConfigValue: valBytes,
				Description: &desc,
			}
			if cerr := db.Create(&row).Error; cerr != nil {
				c.JSON(http.StatusOK, gin.H{"success": false, "error": "保存失败: " + cerr.Error()})
				return
			}
		} else {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "查询配置失败: " + err.Error()})
			return
		}
	} else {
		row.ConfigValue = valBytes
		row.Description = &desc
		if serr := db.Save(&row).Error; serr != nil {
			c.JSON(http.StatusOK, gin.H{"success": false, "error": "保存失败: " + serr.Error()})
			return
		}
	}
	_mbtiAvatarCacheTs = 0
	c.JSON(http.StatusOK, gin.H{"success": true, "message": "MBTI 头像映射已保存"})
}

// AdminMbtiAvatarsBatchAssign POST /api/admin/mbti-avatars/batch-assign
// 为无头像（avatar IS NULL 或空）的用户批量分配 MBTI 默认头像。
// 有 MBTI 的按 MBTI 匹配；无 MBTI 的随机分配。
// 无配置时自动使用 PNG 默认路径。
func AdminMbtiAvatarsBatchAssign(c *gin.Context) {
	db := database.DB()

	avatarMap := make(map[string]string)
	var row model.SystemConfig
	if err := db.Where("config_key = ?", mbtiAvatarsConfigKey).First(&row).Error; err == nil {
		_ = json.Unmarshal(row.ConfigValue, &avatarMap)
	}
	if len(avatarMap) == 0 {
		avatarMap = buildDefaultMbtiAvatarMap()
	}

	availableTypes := make([]string, 0, len(avatarMap))
	for k, v := range avatarMap {
		if v != "" {
			availableTypes = append(availableTypes, k)
		}
	}
	if len(availableTypes) == 0 {
		c.JSON(http.StatusOK, gin.H{"success": false, "error": "无可用头像"})
		return
	}

	var users []model.User
	db.Where("(avatar IS NULL OR avatar = '')").Limit(500).Find(&users)
	if len(users) == 0 {
		c.JSON(http.StatusOK, gin.H{"success": true, "assigned": 0, "message": "无需分配"})
		return
	}

	assigned := 0
	for i := range users {
		mbti := ""
		if users[i].Mbti != nil {
			mbti = *users[i].Mbti
		}
		url := ""
		if mbti != "" {
			url = avatarMap[mbti]
		}
		if url == "" {
			idx := (int(users[i].CreatedAt.UnixNano()) + i) % len(availableTypes)
			url = avatarMap[availableTypes[idx]]
		}
		if url == "" {
			continue
		}
		if err := db.Model(&model.User{}).Where("id = ?", users[i].ID).Update("avatar", url).Error; err == nil {
			assigned++
		}
	}
	c.JSON(http.StatusOK, gin.H{"success": true, "assigned": assigned, "total": len(users), "message": "批量分配完成"})
}