package ezhandler

import "net/http"

func NewHelper(errH ErrorHandler) *Helper {
	return &Helper{errH}
}

// ErrorHandler writes an appropriate response to the [http.ResponseWriter] for the provided [error].
// If the [error] is nil, it should be a no op.
type ErrorHandler func(http.ResponseWriter, *http.Request, error)

// Helper provides methods to make easier, more idiomatic [http.Handler]s.
type Helper struct {
	errHandler ErrorHandler
}

// Handler returns an [http.Handler] for the provided [Handler].
// If hnd returns an error, an appropriate error response is written using the ErrorHandler.
func (help *Helper) Handler(hnd Handler) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if err := hnd.ServeHTTP(w, r); err != nil {
			help.errHandler(w, r, err)
		}
	})
}

// Handler returns an [http.Handler] for the provided [HandlerFunc].
// If hnd returns an error, an appropriate error response is written using the ErrorHandler.
func (help *Helper) HandlerFunc(hnd HandlerFunc) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if err := hnd(w, r); err != nil {
			help.errHandler(w, r, err)
		}
	})
}

// ResponderHandler returns an [http.Handler] for the provided [ResponderHandler].
// If hnd returns an error, an appropriate error response is written using the ErrorHandler.
func (help *Helper) ResponderHandler(hnd ResponseHandler) http.Handler {
	return help.Handler(hnd)
}