package middleware

import (
	"net/http"

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

// CORS 开发期跨域放行；生产同源部署（embed）时不会触发预检。
func CORS() gin.HandlerFunc {
	return func(c *gin.Context) {
		origin := c.GetHeader("Origin")
		if origin != "" {
			c.Header("Access-Control-Allow-Origin", origin)
			c.Header("Access-Control-Allow-Methods", "GET, POST, PUT, DELETE, OPTIONS")
			c.Header("Access-Control-Allow-Headers", "Content-Type, Authorization")
		}
		if c.Request.Method == http.MethodOptions {
			c.AbortWithStatus(http.StatusNoContent)
			return
		}
		c.Next()
	}
}