package handler

import (
	"net/http"
	"strings"
	"unicode"

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

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

// RegisterRoomRoutes 注册蚕房路由
func RegisterRoomRoutes(rg *gin.RouterGroup, db *gorm.DB) {
	rg.GET("/rooms", middleware.RequirePermission(db, "room:read"), listRooms(db))
	rg.GET("/rooms/:id", middleware.RequirePermission(db, "room:read"), getRoom(db))
	rg.POST("/rooms", middleware.RequirePermission(db, "room:write"), createRoom(db))
	rg.PATCH("/rooms/:id", middleware.RequirePermission(db, "room:write"), updateRoom(db))
	rg.DELETE("/rooms/:id", middleware.RequirePermission(db, "room:write"), deleteRoom(db))
}

// listRooms 蚕房列表
func listRooms(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		var rooms []model.Room
		q := applyOrgScope(db.Model(&model.Room{}), c, "org_id")
		q.Order("created_at DESC").Find(&rooms)
		c.JSON(http.StatusOK, rooms)
	}
}

// getRoom 蚕房详情
func getRoom(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		id := c.Param("id")
		if !requireObjectAccess(c, db, "room", id) {
			return
		}
		var room model.Room
		if db.Where("id = ?", id).First(&room).Error != nil {
			c.JSON(http.StatusNotFound, gin.H{"error": "room not found"})
			return
		}
		c.JSON(http.StatusOK, room)
	}
}

// createRoom 新建蚕房
func createRoom(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		var room model.Room
		if err := c.ShouldBindJSON(&room); err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		room.ID = "" // 让数据库自动生成
		if room.OrgID == nil {
			room.OrgID = defaultOrgID(db, c)
		} else if !canAccessOrganization(db, c, *room.OrgID) {
			c.JSON(http.StatusForbidden, gin.H{"error": "无权在该组织下创建蚕房"})
			return
		}
		if err := db.Create(&room).Error; err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": "创建失败"})
			return
		}
		c.JSON(http.StatusCreated, room)
	}
}

// updateRoom 更新蚕房
func updateRoom(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		id := c.Param("id")
		if !requireObjectAccess(c, db, "room", id) {
			return
		}
		var room model.Room
		if db.Where("id = ?", id).First(&room).Error != nil {
			c.JSON(http.StatusNotFound, gin.H{"error": "room not found"})
			return
		}
		updates, err := bindUpdates(c)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
			return
		}
		if orgID, ok := updates["org_id"]; ok {
			if orgStr, ok := orgID.(string); ok && !canAccessOrganization(db, c, orgStr) {
				c.JSON(http.StatusForbidden, gin.H{"error": "无权迁移蚕房到该组织"})
				return
			}
		}
		if len(updates) > 0 {
			db.Model(&model.Room{}).Where("id = ?", id).Updates(updates)
		}
		db.Where("id = ?", id).First(&room)
		c.JSON(http.StatusOK, room)
	}
}

// deleteRoom 删除蚕房
func deleteRoom(db *gorm.DB) gin.HandlerFunc {
	return func(c *gin.Context) {
		id := c.Param("id")
		if !requireObjectAccess(c, db, "room", id) {
			return
		}
		var room model.Room
		if db.Where("id = ?", id).First(&room).Error != nil {
			c.JSON(http.StatusNotFound, gin.H{"error": "room not found"})
			return
		}
		db.Where("id = ?", id).Delete(&model.Room{})
		c.JSON(http.StatusOK, gin.H{"id": id})
	}
}

// camelToSnake 将 camelCase 转为 snake_case（供所有 CRUD handler 复用）
func camelToSnake(s string) string {
	var result strings.Builder
	for i, r := range s {
		if i > 0 && unicode.IsUpper(r) {
			result.WriteRune('_')
		}
		result.WriteRune(unicode.ToLower(r))
	}
	return result.String()
}

// bindUpdates 绑定 JSON body 并转为 snake_case 的 map（排除不可更新字段）
func bindUpdates(c *gin.Context) (map[string]interface{}, error) {
	var body map[string]interface{}
	if err := c.ShouldBindJSON(&body); err != nil {
		return nil, err
	}
	updates := make(map[string]interface{})
	for k, v := range body {
		// 排除不可更新字段
		if k == "id" || k == "createdAt" || k == "updatedAt" {
			continue
		}
		updates[camelToSnake(k)] = v
	}
	return updates, nil
}