package tower

import (
	"context"
	"log"
	"net/http"

	"github.com/julienschmidt/httprouter"
)

type Tower struct {
	router            *httprouter.Router
	errorHandler      ErrorHandler
	globalMiddlewares []Middleware
	server            *http.Server
}

func New() *Tower {
	t := &Tower{
		router:            httprouter.New(),
		errorHandler:      defaultErrorHandler,
		globalMiddlewares: []Middleware{},
	}

	t.server = &http.Server{
		Handler: t.router,
	}

	return t
}

func (t *Tower) Start(listenAddr string) error {
	t.server.Addr = listenAddr
	return t.server.ListenAndServe()
}

func (t *Tower) StartTLS(listenAddr, certFile, keyFile string) error {
	t.server.Addr = listenAddr
	return t.server.ListenAndServeTLS(certFile, keyFile)
}

func (t *Tower) Shutdown(ctx context.Context) error {
	return t.server.Shutdown(ctx)
}

func (t *Tower) SetErrorHandler(errorHandler ErrorHandler) {
	t.errorHandler = errorHandler
}

func (t *Tower) Use(globalMiddlewares ...Middleware) {
	t.globalMiddlewares = append(t.globalMiddlewares, globalMiddlewares...)
}

func (t *Tower) Group(prefix string, groupMiddlewares ...Middleware) *Group {
	return &Group{
		prefix:           normalizePath(prefix),
		parent:           t,
		groupMiddlewares: groupMiddlewares,
	}
}

func (t *Tower) Static(prefix, dir string) {
	prefix = normalizePath(prefix)
	prefix += "/*filepath"

	t.router.ServeFiles(prefix, http.Dir(dir))
}

func (t *Tower) GET(path string, h Handler, routeMiddlewares ...Middleware) {
	t.Handle(http.MethodGet, path, h, routeMiddlewares...)
}

func (t *Tower) POST(path string, h Handler, routeMiddlewares ...Middleware) {
	t.Handle(http.MethodPost, path, h, routeMiddlewares...)
}

func (t *Tower) PUT(path string, h Handler, routeMiddlewares ...Middleware) {
	t.Handle(http.MethodPut, path, h, routeMiddlewares...)
}

func (t *Tower) PATCH(path string, h Handler, routeMiddlewares ...Middleware) {
	t.Handle(http.MethodPatch, path, h, routeMiddlewares...)
}

func (t *Tower) DELETE(path string, h Handler, routeMiddlewares ...Middleware) {
	t.Handle(http.MethodDelete, path, h, routeMiddlewares...)
}

func (t *Tower) Handle(method string, path string, h Handler, routeMiddlewares ...Middleware) {
	t.router.Handle(method, path, t.buildHTTPRouterHandle(h, routeMiddlewares...))
}

func (t *Tower) buildHTTPRouterHandle(h Handler, routeMiddlewares ...Middleware) httprouter.Handle {
	return func(w http.ResponseWriter, r *http.Request, p httprouter.Params) {
		ctx := Context{
			request:  r,
			response: &responseWriter{ResponseWriter: w},
			params:   p,
		}

		wrappedHandler := h

		for i := len(routeMiddlewares) - 1; i >= 0; i-- {
			wrappedHandler = routeMiddlewares[i](wrappedHandler)
		}

		for i := len(t.globalMiddlewares) - 1; i >= 0; i-- {
			wrappedHandler = t.globalMiddlewares[i](wrappedHandler)
		}

		if err := wrappedHandler(&ctx); err != nil {
			if err := t.errorHandler(&ctx, err); err != nil {
				log.Printf("[Error] %v", err)
			}
		}
	}
}