package web

import (
	"fmt"

	"gitlab.quimbo.fr/odwrtw/canape-sql/auth"
	"gitlab.quimbo.fr/odwrtw/canape-sql/config"

	"github.com/Sirupsen/logrus"
	"github.com/codegangsta/negroni"
	"github.com/gorilla/mux"
	"github.com/jmoiron/sqlx"
	"github.com/unrolled/render"
)

// Env describes an environement object passed to all handlers
type Env struct {
	Database   *sqlx.DB
	Log        *logrus.Entry
	Router     *mux.Router
	Render     *render.Render
	Auth       *auth.Authorizer
	Config     *config.Config
	loginRoute string
}

// EnvParams represents parameters for NewEnv
type EnvParams struct {
	Database     *sqlx.DB
	Auth         *auth.Authorizer
	Log          *logrus.Entry
	Config       *config.Config
	TemplatesDir string
}

// NewEnv returns a new *Env
func NewEnv(p EnvParams) *Env {
	e := &Env{
		Database: p.Database,
		Log:      p.Log,
		Router:   mux.NewRouter(),
		Auth:     p.Auth,
		Config:   p.Config,
	}

	tmplFuncs = append(tmplFuncs, map[string]interface{}{
		"URL": func(name string, pairs ...string) (string, error) {
			return e.GetURL(name, pairs...)
		},
	})

	e.Render = render.New(render.Options{
		Directory: p.TemplatesDir,
		Layout:    "layout",
		Funcs:     tmplFuncs,
		DisableHTTPErrorRendering: true,
		RequirePartials:           true,
	})
	return e
}

type Route struct {
	env    *Env
	mRoute *mux.Route
}

func (r *Route) Name(name string) *Route {
	r.mRoute.Name(name)
	return r
}

func (r *Route) Methods(methods ...string) *Route {
	r.mRoute.Methods(methods...)
	return r
}

func (r *Route) WithRole(role string) *Route {
	handler := r.mRoute.GetHandler()
	newHandler := negroni.New(
		auth.NewMiddlewareRole(r.env.Auth, r.env.GetLoginRouteGetter(), role),
		negroni.Wrap(handler))
	r.mRoute.Handler(newHandler)
	return r
}

// Handle add route
func (e *Env) Handle(route string, H HandlerFunc) *Route {
	mRoute := e.Router.Handle(route, Handler{e, H})
	return &Route{
		env:    e,
		mRoute: mRoute,
	}
}

// GetURL returns URL string from URL name and params
// Usefull for redirection and templates
func (e *Env) GetURL(name string, pairs ...string) (string, error) {
	route := e.Router.Get(name)
	if route == nil {
		return "", fmt.Errorf("No route find for the given name: %s", name)
	}
	URL, err := route.URL(pairs...)
	if err != nil {
		return "", err
	}
	return URL.String(), nil
}

// SetLoginRoute sets the route name of login page for further use
// with GetLoginRouteGetter
func (e *Env) SetLoginRoute(name string) error {
	route, err := e.GetURL(name)
	if err != nil {
		return err
	}
	e.loginRoute = route
	return nil
}

// GetLoginRouteGetter allow some code parts like middleware access
// to login route name
func (e *Env) GetLoginRouteGetter() func() string {
	return func() string {
		if e.loginRoute == "" {
			panic("Env: login route not set")
		}
		return e.loginRoute
	}
}