package middleware

import "net/http"

// Chain 中间件链
type Chain struct {
	middlewares []func(http.Handler) http.Handler
}

// NewChain 创建新的中间件链
func NewChain(middlewares ...func(http.Handler) http.Handler) *Chain {
	return &Chain{
		middlewares: middlewares,
	}
}

// Then 将中间件链应用到处理器
func (c *Chain) Then(handler http.Handler) http.Handler {
	final := handler
	for i := len(c.middlewares) - 1; i >= 0; i-- {
		final = c.middlewares[i](final)
	}
	return final
}

// ThenFunc 将中间件链应用到处理器函数
func (c *Chain) ThenFunc(handler http.HandlerFunc) http.Handler {
	return c.Then(handler)
}

// Append 追加中间件
func (c *Chain) Append(middlewares ...func(http.Handler) http.Handler) *Chain {
	c.middlewares = append(c.middlewares, middlewares...)
	return c
}