package main

import (
	"bufio"
	"database/sql"
	"log"
	"os"
	"strings"
	"time"

	"github.com/gofiber/fiber/v2"
	"github.com/golang-jwt/jwt/v5"
	_ "github.com/lib/pq"
)

type MyCustomClaims struct {
	Email string `json:"email"`
	jwt.RegisteredClaims
}

type User struct {
	Email  string
	First  string
	Last   string
	City   string
	County string
	Age    int
}

var jwtSecret = "mysuperPUPERsecret100500security"

func getToken(c *fiber.Ctx) string {
	hdr := c.Get("Authorization")
	if hdr == "" {
		return ""
	}

	token := strings.Split(hdr, "Bearer ")[1]
	return token
}

func main() {
	app := fiber.New()
	db, err := sql.Open("postgres", "user=postgres password=123456 dbname=testbench sslmode=disable")

	if err != nil {
		return
	}

	defer db.Close()

	db.SetMaxOpenConns(10)
	db.SetMaxIdleConns(10)

	app.Get("/", func(c *fiber.Ctx) error {
		tokenString := getToken(c)
		if tokenString == "" {
			return c.SendStatus(fiber.StatusUnauthorized)
		}
		token, err := jwt.ParseWithClaims(tokenString, &MyCustomClaims{}, func(token *jwt.Token) (interface{}, error) {
			return []byte(jwtSecret), nil
		})

		if err != nil {
			log.Println(err)
			return c.SendStatus(fiber.StatusUnauthorized)
		}

		claims := token.Claims.(*MyCustomClaims)

		query := "SELECT * FROM users WHERE email=$1"
		row := db.QueryRow(query, claims.Email)

		var user User = User{}
		err2 := row.Scan(&user.Email, &user.First, &user.Last, &user.County, &user.City, &user.Age)
		if err2 == sql.ErrNoRows {
			return c.SendStatus(fiber.StatusNotFound)
		}
		if err2 != nil {
			log.Println(err2)
			return c.SendStatus(fiber.StatusInternalServerError)
		}

		return c.JSON(user)
	})

	//вспомогательная ручка
	app.Get("/randomtoken", func(c *fiber.Ctx) error {
		file, err := os.Create("tokens.txt")
		if err != nil {
			log.Println(err)
			return c.SendStatus(fiber.StatusInternalServerError)
		}

		writer := bufio.NewWriter(file)

		rows, err := db.Query("SELECT * FROM USERS OFFSET floor(random() * 100000) LIMIT 10")
		if err != nil {
			return c.SendStatus(fiber.StatusInternalServerError)
		}

		for rows.Next() {
			var user User
			err = rows.Scan(&user.Email, &user.First, &user.Last, &user.County, &user.City, &user.Age)
			if err != nil {
				log.Println(err)
				return c.SendStatus(fiber.StatusInternalServerError)
			}

			claims := MyCustomClaims{
				user.Email,
				jwt.RegisteredClaims{
					ExpiresAt: jwt.NewNumericDate(time.Now().Add(24 * time.Hour)),
				},
			}

			token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
			ss, err := token.SignedString([]byte(jwtSecret))

			if err != nil {
				log.Println(err)
				return c.SendStatus(fiber.StatusInternalServerError)
			}

			_, err = writer.WriteString(ss + "\n")
			if err != nil {
				file.Close()
				log.Println(err)
				return c.SendStatus(fiber.StatusInternalServerError)
			}

		}

		writer.Flush()
		file.Close()

		return c.SendFile(file.Name())
	})

	log.Fatal(app.Listen(":3000"))
}

use axum::{
    extract::State,
    http::{header::AUTHORIZATION, HeaderMap, StatusCode},
    response::IntoResponse,
    routing::get,
    Json, Router,
};
use jsonwebtoken::{decode, Algorithm, DecodingKey, Validation};
use serde::{Deserialize, Serialize};
use sqlx::{postgres::PgPoolOptions, Pool, Postgres};

#[derive(Debug, Serialize, Deserialize)]
struct Claims {
    email: String,
    exp: usize,
}

#[derive(Debug, Deserialize, Serialize, sqlx::FromRow)]
pub struct User {
    pub email: String,
    pub first: Option<String>,
    pub last: Option<String>,
    pub city: Option<String>,
    pub county: Option<String>,
    pub age: Option<i32>,
}

type ConnectionPool = Pool<Postgres>;

async fn root(headers: HeaderMap, State(pool): State<ConnectionPool>) -> impl IntoResponse {
    let jwt_secret = "mysuperPUPERsecret100500security";
    let validation = Validation::new(Algorithm::HS256);

    let auth_header = headers.get(AUTHORIZATION).expect("no authorization header");
    let mut auth_hdr: &str = auth_header.to_str().unwrap();
    auth_hdr = &auth_hdr.strip_prefix("Bearer ").unwrap();

    let token = match decode::<Claims>(
        &auth_hdr,
        &DecodingKey::from_secret(jwt_secret.as_ref()),
        &validation,
    ) {
        Ok(c) => c,
        Err(e) => {
            eprintln!("Application error: {e}");
            return (StatusCode::INTERNAL_SERVER_ERROR, "invalid token").into_response();
        }
    };

    let email = token.claims.email;
    let query_result: Result<User, sqlx::Error> =
        sqlx::query_as(r#"SELECT *  FROM USERS WHERE email=$1"#)
            .bind(email)
            .fetch_one(&pool)
            .await;

    match query_result {
        Ok(user) => {
            return (StatusCode::ACCEPTED, Json(user)).into_response();
        }
        Err(sqlx::Error::RowNotFound) => {
            return (StatusCode::NOT_FOUND, "user not found").into_response();
        }
        Err(_e) => {
            println!("error: {}", _e.to_string());
            return (StatusCode::INTERNAL_SERVER_ERROR, "error").into_response();
        }
    };
}

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let database_url = String::from("postgres://postgres:123456@localhost/testbench");
    let pool = PgPoolOptions::new()
        .max_connections(10)
        .connect(&database_url)
        .await
        .expect("can't connect to database");

    println!("DB connect success");

    let app = Router::new()
        .route("/", get(root))
        .with_state(pool);

    let listener = tokio::net::TcpListener::bind("127.0.0.1:3000")
        .await
        .unwrap();
    axum::serve(listener, app).await?;
    Ok(())
}

// NOTE ----
// Rust code has been built in release mode for all performance tests