package db

import (
	"context"
	"time"

	"golang.org/x/crypto/bcrypt"
)

type User struct {
	ID           int       `json:"id"`
	Username     string    `json:"username"`
	PasswordHash string    `json:"-"`
	CreatedAt    time.Time `json:"created_at"`
}

type CreateUserRequest struct {
	Username string `json:"username"`
	Password string `json:"password"`
}

type LoginRequest struct {
	Username string `json:"username"`
	Password string `json:"password"`
}

func CreateUser(ctx context.Context, req CreateUserRequest) (*User, error) {
	hashedPassword, err := bcrypt.GenerateFromPassword([]byte(req.Password), bcrypt.DefaultCost)
	if err != nil {
		return nil, err
	}

	var user User
	err = Pool.QueryRow(ctx,
		"INSERT INTO users (username, password_hash) VALUES ($1, $2) RETURNING id, username, created_at",
		req.Username, string(hashedPassword),
	).Scan(&user.ID, &user.Username, &user.CreatedAt)

	if err != nil {
		return nil, err
	}

	return &user, nil
}

func GetUserByUsername(ctx context.Context, username string) (*User, error) {
	var user User
	err := Pool.QueryRow(ctx,
		"SELECT id, username, password_hash, created_at FROM users WHERE username = $1",
		username,
	).Scan(&user.ID, &user.Username, &user.PasswordHash, &user.CreatedAt)

	if err != nil {
		return nil, err
	}

	return &user, nil
}

func ValidateUserCredentials(ctx context.Context, username, password string) (*User, error) {
	user, err := GetUserByUsername(ctx, username)
	if err != nil {
		return nil, err
	}

	err = bcrypt.CompareHashAndPassword([]byte(user.PasswordHash), []byte(password))
	if err != nil {
		return nil, err
	}

	return user, nil
}