package auth

import (
	"database/sql"
	"net/http"

	"github.com/alexedwards/scs/v2"
	"github.com/google/uuid"
	"github.com/starfederation/datastar-go/datastar"

	"github.com/ryanhamamura/games/auth"
	"github.com/ryanhamamura/games/db/repository"
	"github.com/ryanhamamura/games/features/auth/pages"
)

type LoginSignals struct {
	Username string `json:"username"`
	Password string `json:"password"` //nolint:gosec // form input, not stored
}

type RegisterSignals struct {
	Username string `json:"username"`
	Password string `json:"password"` //nolint:gosec // form input, not stored
	Confirm  string `json:"confirm"`
}

func HandleLoginPage() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if err := pages.LoginPage().Render(r.Context(), w); err != nil {
			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
		}
	}
}

func HandleRegisterPage() http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		if err := pages.RegisterPage().Render(r.Context(), w); err != nil {
			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
		}
	}
}

func HandleLogin(queries *repository.Queries, sessions *scs.SessionManager) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var signals LoginSignals
		if err := datastar.ReadSignals(r, &signals); err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}

		sse := datastar.NewSSE(w, r)

		user, err := queries.GetUserByUsername(r.Context(), signals.Username)
		if err == sql.ErrNoRows {
			sse.MarshalAndPatchSignals(map[string]any{"error": "Invalid username or password"}) //nolint:errcheck
			return
		}
		if err != nil {
			sse.MarshalAndPatchSignals(map[string]any{"error": "An error occurred"}) //nolint:errcheck
			return
		}
		if !auth.CheckPassword(signals.Password, user.PasswordHash) {
			sse.MarshalAndPatchSignals(map[string]any{"error": "Invalid username or password"}) //nolint:errcheck
			return
		}

		sessions.RenewToken(r.Context()) //nolint:errcheck
		sessions.Put(r.Context(), "user_id", user.ID)
		sessions.Put(r.Context(), "username", user.Username)
		sessions.Put(r.Context(), "nickname", user.Username)

		redirectURL := "/"
		if returnURL := sessions.GetString(r.Context(), "return_url"); returnURL != "" {
			sessions.Put(r.Context(), "return_url", "")
			redirectURL = returnURL
		}

		sse.Redirect(redirectURL) //nolint:errcheck
	}
}

func HandleRegister(queries *repository.Queries, sessions *scs.SessionManager) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		var signals RegisterSignals
		if err := datastar.ReadSignals(r, &signals); err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}

		sse := datastar.NewSSE(w, r)

		if err := auth.ValidateUsername(signals.Username); err != nil {
			sse.MarshalAndPatchSignals(map[string]any{"error": err.Error()}) //nolint:errcheck
			return
		}
		if err := auth.ValidatePassword(signals.Password); err != nil {
			sse.MarshalAndPatchSignals(map[string]any{"error": err.Error()}) //nolint:errcheck
			return
		}
		if signals.Password != signals.Confirm {
			sse.MarshalAndPatchSignals(map[string]any{"error": "Passwords do not match"}) //nolint:errcheck
			return
		}

		hash, err := auth.HashPassword(signals.Password)
		if err != nil {
			sse.MarshalAndPatchSignals(map[string]any{"error": "An error occurred"}) //nolint:errcheck
			return
		}

		user, err := queries.CreateUser(r.Context(), repository.CreateUserParams{
			ID:           uuid.New().String(),
			Username:     signals.Username,
			PasswordHash: hash,
		})
		if err != nil {
			sse.MarshalAndPatchSignals(map[string]any{"error": "Username already taken"}) //nolint:errcheck
			return
		}

		sessions.RenewToken(r.Context()) //nolint:errcheck
		sessions.Put(r.Context(), "user_id", user.ID)
		sessions.Put(r.Context(), "username", user.Username)
		sessions.Put(r.Context(), "nickname", user.Username)

		redirectURL := "/"
		if returnURL := sessions.GetString(r.Context(), "return_url"); returnURL != "" {
			sessions.Put(r.Context(), "return_url", "")
			redirectURL = returnURL
		}

		sse.Redirect(redirectURL) //nolint:errcheck
	}
}