package app

import (
	"errors"
	md "farga/app/middleware"
	"farga/app/templating"
	db "farga/db"
	"farga/db/types"
	"farga/lib"
	"io"
	"net/http"
	"strings"
)

type RegisterForm struct {
	Name     string `form:"name"     validate:"required,max=40"`
	Handle   string `form:"handle"   validate:"required,min=3,max=30"`
	Email    string `form:"email"    validate:"required,email"`
	Password string `form:"password" validate:"required,min=8"`
}

type LoginForm struct {
	Email    string `form:"email"    validate:"required,email"`
	Password string `form:"password" validate:"required,min=8"`
}

func (a *App) login(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case "GET":
		templating.Render(w, r, "base", "login")
	case "POST":
		form, _ := md.Form[LoginForm](r)
		user, err := a.Store.LoginUser(form.Email, form.Password)
		if err != nil && (errors.Is(err, db.UserNotFound) || errors.Is(err, db.IncorrectPassword)) { // user not found or incorrect password
			http.Redirect(w, r, "/auth/login?err=InvalidCredentials", http.StatusSeeOther)
			return
		}

		session, err := a.Store.NewSession(&user.ID)

		if err != nil {
			io.WriteString(w, "Something went wrong while creating your session.")
			return
		}

		lib.SetCookie(w, "session", session.ID.String())
		http.Redirect(w, r, "/?msg=AuthSuccess", http.StatusSeeOther)
	}
}

func (a *App) register(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case "GET":
		templating.Render(w, r, "base", "register", map[string]any{
			"HandleRegex": lib.HandleRegex.String(),
		})
	case "POST":
		form, _ := md.Form[RegisterForm](r)

		if !lib.ValidateHandle(form.Handle) {
			http.Redirect(w, r, "?err=UserInvalidHandle", http.StatusSeeOther)
			return
		}

		password, err := lib.GenerateHash(form.Password)
		if err != nil {
			http.Error(w, "Something went wrong while generating your password's hash. Please try again!", 500)
			return
		}
		user := types.User{
			Name:         strings.TrimSpace(form.Name),
			Handle:       strings.TrimSpace(form.Handle),
			Email:        strings.TrimSpace(form.Email),
			PasswordHash: password,
			Config: types.UserConfig{
				GitDefaultBranch: lib.GitDefaultBranch,
			},
		}

		err = a.Store.NewUser(&user)

		if err != nil {
			constrainedField := strings.Replace(err.Error(), "UNIQUE constraint failed: users.", "That ", 1) + " has already been claimed."
			http.Error(w, constrainedField, 500)
			return
		}

		session, err := a.Store.NewSession(&user.ID)

		if err != nil {
			io.WriteString(w, "Goddammit! Something went wrong while creating your session. Try logging in instead.")
			return
		}

		lib.SetCookie(w, "session", session.ID.String())

		http.Redirect(w, r, "/?msg=AuthSuccess", http.StatusTemporaryRedirect)
	}
}

func (a *App) logout(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case "GET":
		templating.Render(w, r, "base", "logout")
	case "POST":
		session := r.Context().Value(lib.SessionKey).(string)

		err := a.Store.RemoveSession(session)
		if err != nil {
			io.WriteString(w, "Something went wrong while deleting your session: "+err.Error())
			return
		}

		lib.DeleteCookie(w, "session")
		http.Redirect(w, r, "/auth/login?msg=LogoutSuccess", http.StatusFound)
	}
}