package server

import (
	"fmt"
	"log/slog"
	"net/http"
	"strings"

	"shlf.space/internal/server/htmx"
	"shlf.space/internal/views/login"
)

func (s *Server) Login(w http.ResponseWriter, r *http.Request) {
	switch r.Method {
	case http.MethodGet:
		returnURL := r.URL.Query().Get("return_url")
		errorCode := r.URL.Query().Get("error")
		login.LoginPage(login.LoginPageParams{
			ReturnUrl: returnURL,
			ErrorCode: errorCode,
		}).Render(r.Context(), w)
	case http.MethodPost:
		handle := r.FormValue("handle")
		returnURL := r.FormValue("return_url")

		// When users copy their handle from bsky.app, it tends to have these
		// characters around it:
		//
		// @nelind.dk:
		//   \u202a ensures that the handle is always rendered left to right and
		//   \u202c reverts that so the rest of the page renders however it should
		handle = strings.TrimPrefix(handle, "\u202a")
		handle = strings.TrimSuffix(handle, "\u202c")

		// `@` is harmless
		handle = strings.TrimPrefix(handle, "@")

		// Basic handle validation
		if !strings.Contains(handle, ".") {
			htmx.HxNotice(w, "login-msg", fmt.Sprintf("'%s' is an invalid handle. Did you mean %s.bsky.social?", handle, handle))
			return
		}

		if err := s.oauth.SetAuthReturn(w, r, returnURL); err != nil {
			slog.Error("failed to set auth return", "err", err)
		}

		redirectURL, err := s.oauth.ClientApp.StartAuthFlow(r.Context(), handle)
		if err != nil {
			htmx.HxNotice(w, "login-msg", fmt.Sprintf("Failed to start auth flow: %v", err))
			return
		}

		htmx.HxRedirect(w, http.StatusOK, redirectURL)
	}
}