package users

import (
	"fmt"
	"net/http"

	"github.com/gorilla/mux"
	"github.com/mholt/binding"
	"gitlab.quimbo.fr/odwrtw/canape-sql/auth"
	"gitlab.quimbo.fr/odwrtw/canape-sql/web"
)

// FormErrors map[field name]message
type FormErrors map[string]string

// HandleFormErrors translate binding.Erros to FormErrors
func HandleFormErrors(errs binding.Errors) FormErrors {
	ferrs := FormErrors{}
	for _, err := range errs {
		for _, field := range err.FieldNames {
			if ferrs[field] == "" {
				ferrs[field] = err.Message
			}
		}
	}
	return ferrs
}

type loginForm struct {
	Username string
	Password string
}

func (f *loginForm) FieldMap(r *http.Request) binding.FieldMap {
	return binding.FieldMap{
		&f.Username: "username",
		&f.Password: "password",
	}
}

func (f *loginForm) Validate(r *http.Request, errs binding.Errors) binding.Errors {
	if f.Username == "" {
		errs = append(errs, binding.Error{
			FieldNames:     []string{"username"},
			Classification: "InvalidValues",
			Message:        "Specify a username",
		})
	}
	if f.Password == "" {
		errs = append(errs, binding.Error{
			FieldNames:     []string{"password"},
			Classification: "InvalidValues",
			Message:        "Specify a password",
		})
	}
	return errs
}

func loginSubmitHandler(e *web.Env, w http.ResponseWriter, r *http.Request) error {
	form := new(loginForm)

	errs := binding.Bind(r, form)
	if errs != nil {
		formErrs := HandleFormErrors(errs)
		web.SetData(r, "FormErrors", formErrs)
		return e.Rends(w, r, "users/login")
	}

	err := e.Auth.Login(w, r, form.Username, form.Password)
	if err != nil {
		if err == auth.ErrInvalidPassword || err == ErrUnknownUser {
			web.SetData(r, "FormErrors", FormErrors{"password": "Invalid username or password"})
			return e.Rends(w, r, "users/login")
		}
		return web.InternalError(err)
	}

	return nil
}

func userDetailsHandler(e *web.Env, w http.ResponseWriter, r *http.Request) error {
	u, err := e.Auth.CurrentUser(w, r)
	if err != nil {
		return err
	}
	if u == nil {
		return nil
	}
	_, ok := u.(*User)
	if !ok {
		return fmt.Errorf("Invalid user type")
	}
	return nil
}

// SetRoutes adds users routes to the router
func SetRoutes(r *mux.Router, e *web.Env) {
	r.Handle("/login", e.Handler(loginSubmitHandler)).Methods("POST").Name("loginPost")
	r.Handle("/", e.Handler(userDetailsHandler)).Methods("GET").Name("UserDetails")
}