package handler

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

	"silk-server-go/internal/middleware"
	"silk-server-go/internal/model"
	"silk-server-go/internal/service"

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

// RegisterWechatRoutes 注册微信订阅消息路由（骨架，配置占位）
func RegisterWechatRoutes(rg *gin.RouterGroup, db *gorm.DB, wechat *service.WechatService) {
	read := middleware.RequirePermission(db, "notification:read")
	write := middleware.RequirePermission(db, "notification:write")
	rg.GET("/wechat/binding", read, getWechatBinding(db))
	rg.POST("/wechat/bind", write, bindWechat(db, wechat))
	rg.POST("/wechat/subscribe", write, updateWechatSubscribe(db))
}

// getWechatBinding 当前用户的微信绑定与授权模板
func getWechatBinding(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		uid := currentUserID(c)
		if uid == nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "未登录"})
			return
		}
		var b model.WechatBinding
		if db.Where("user_id = ?", *uid).First(&b).Error != nil {
			c.JSON(http.StatusOK, gin.H{"bound": false})
			return
		}
		c.JSON(http.StatusOK, gin.H{
			"bound":     true,
			"openId":    b.OpenID,
			"authorized": b.AuthorizedTemplates,
		})
	}
}

// bindWechat 用 wx.login 的 code 换 openid 并绑定当前用户
func bindWechat(db *gorm.DB, wechat *service.WechatService) gin.HandlerFunc {
	return func(c *gin.Context) {
		uid := currentUserID(c)
		if uid == nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "未登录"})
			return
		}
		var body struct {
			Code string `json:"code"`
		}
		if err := c.ShouldBindJSON(&body); err != nil || body.Code == "" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "缺少 code"})
			return
		}
		openid, err := wechat.Code2Session(c.Request.Context(), body.Code)
		if err != nil {
			c.JSON(http.StatusBadGateway, gin.H{"error": err.Error()})
			return
		}
		var b model.WechatBinding
		if db.Where("user_id = ?", *uid).First(&b).Error != nil {
			b = model.WechatBinding{UserID: *uid, OpenID: openid}
			if err := db.Create(&b).Error; err != nil {
				c.JSON(http.StatusInternalServerError, gin.H{"error": "绑定失败"})
				return
			}
		} else {
			db.Model(&model.WechatBinding{}).Where("id = ?", b.ID).Update("open_id", openid)
		}
		c.JSON(http.StatusOK, gin.H{"bound": true, "openId": openid})
	}
}

// updateWechatSubscribe 更新用户对某场景的订阅授权（alarm/inspection）
func updateWechatSubscribe(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		uid := currentUserID(c)
		if uid == nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "未登录"})
			return
		}
		var body struct {
			Template   string `json:"template"`
			Authorized bool   `json:"authorized"`
		}
		if err := c.ShouldBindJSON(&body); err != nil || body.Template == "" {
			c.JSON(http.StatusBadRequest, gin.H{"error": "缺少 template"})
			return
		}
		var b model.WechatBinding
		if db.Where("user_id = ?", *uid).First(&b).Error != nil {
			c.JSON(http.StatusNotFound, gin.H{"error": "请先绑定微信"})
			return
		}
		var templates []string
		if len(b.AuthorizedTemplates) > 0 {
			_ = json.Unmarshal(b.AuthorizedTemplates, &templates)
		}
		templates = toggleTemplate(templates, body.Template, body.Authorized)
		raw, _ := json.Marshal(templates)
		db.Model(&model.WechatBinding{}).Where("id = ?", b.ID).Update("authorized_templates", raw)
		c.JSON(http.StatusOK, gin.H{"authorized": templates})
	}
}

// toggleTemplate 增删授权模板键
func toggleTemplate(list []string, key string, add bool) []string {
	out := make([]string, 0, len(list))
	exists := false
	for _, k := range list {
		if k == key {
			exists = true
			if add {
				out = append(out, k)
			}
			continue
		}
		out = append(out, k)
	}
	if add && !exists {
		out = append(out, key)
	}
	return out
}