package handlers

import (
	"bookmann/internal/database"
	"context"
	"net/http"
	"time"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgtype"
	"github.com/labstack/echo/v4"
)

const (
	refreshTokenExpiration = 7 * 24 * time.Hour // 7 days
)

type RefreshTokenRequest struct {
	RefreshToken string `json:"refresh_token" validate:"required"`
}

type RefreshTokenResponse struct {
	AccessToken string `json:"access_token"`
	TokenType   string `json:"token_type"`
	ExpiresIn   int    `json:"expires_in"` // seconds
}

// RefreshAccessToken handles POST /api/auth/refresh
func (h *AuthHandler) RefreshAccessToken(c echo.Context) error {
	var req RefreshTokenRequest
	if err := c.Bind(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": "invalid request"})
	}
	if err := c.Validate(&req); err != nil {
		return c.JSON(http.StatusBadRequest, map[string]string{"error": err.Error()})
	}

	// Get refresh token from database
	tokenInfo, err := h.db.GetRefreshToken(c.Request().Context(), req.RefreshToken)
	if err != nil {
		if err == pgx.ErrNoRows {
			return c.JSON(http.StatusUnauthorized, map[string]string{"error": "invalid or expired refresh token"})
		}
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": "failed to validate refresh token"})
	}

	// Generate new access token
	accessToken, err := h.generateJWTWithAllClaims(
		uuid.UUID(tokenInfo.UserID.Bytes).String(),
		tokenInfo.Role,
		tokenInfo.Email,
		tokenInfo.Username,
	)
	if err != nil {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": "failed to generate access token"})
	}

	return c.JSON(http.StatusOK, RefreshTokenResponse{
		AccessToken: accessToken,
		TokenType:   "Bearer",
		ExpiresIn:   3600, // 1 hour in seconds
	})
}

// Logout handles POST /api/auth/logout
func (h *AuthHandler) Logout(c echo.Context) error {
	var req RefreshTokenRequest
	if err := c.Bind(&req); err != nil {
		// If no refresh token provided, just return success
		return c.JSON(http.StatusOK, map[string]string{"message": "logged out successfully"})
	}

	// Revoke the refresh token if provided
	err := h.db.RevokeRefreshToken(c.Request().Context(), req.RefreshToken)
	if err != nil && err != pgx.ErrNoRows {
		return c.JSON(http.StatusInternalServerError, map[string]string{"error": "failed to revoke refresh token"})
	}

	return c.JSON(http.StatusOK, map[string]string{"message": "logged out successfully"})
}

// CreateRefreshToken creates a new refresh token for a user
func (h *AuthHandler) CreateRefreshToken(userID uuid.UUID) (string, string, error) {
	// Generate refresh token
	tokenUUID := uuid.New()
	refreshToken := tokenUUID.String()

	// Store in database (plain text for simplicity - tokens are already random UUIDs)
	expiresAt := time.Now().Add(refreshTokenExpiration)
	_, err := h.db.CreateRefreshToken(context.Background(), database.CreateRefreshTokenParams{
		UserID:    pgtype.UUID{Bytes: [16]byte(userID), Valid: true},
		Token:     refreshToken,
		ExpiresAt: pgtype.Timestamptz{Time: expiresAt, Valid: true},
	})
	if err != nil {
		return "", "", err
	}

	// Generate new access token
	accessToken, err := h.generateJWT(userID.String())
	if err != nil {
		return "", "", err
	}

	return accessToken, refreshToken, nil
}