package models

import (
	"context"
	"database/sql"
	"fmt"
	"time"

	"github.com/jmoiron/sqlx"
)

// User represents a user in the system
type User struct {
	ID         string    `db:"id" json:"id"`
	OpenID     string    `db:"openid" json:"openid"`
	SessionKey string    `db:"session_key" json:"-"`
	CreatedAt  time.Time `db:"created_at" json:"created_at"`
	UpdatedAt  time.Time `db:"updated_at" json:"updated_at"`
}

// UserRepository handles user data operations
type UserRepository struct {
	db *sqlx.DB
}

// NewUserRepository creates a new UserRepository
func NewUserRepository(db *sqlx.DB) *UserRepository {
	return &UserRepository{db: db}
}

// FindByID finds a user by ID
func (r *UserRepository) FindByID(ctx context.Context, id string) (*User, error) {
	var user User
	query := `SELECT * FROM users WHERE id = ?`
	err := r.db.GetContext(ctx, &user, query, id)
	if err != nil {
		if err == sql.ErrNoRows {
			return nil, fmt.Errorf("user not found: %w", err)
		}
		return nil, fmt.Errorf("failed to find user: %w", err)
	}
	return &user, nil
}

// FindByOpenID finds a user by OpenID
func (r *UserRepository) FindByOpenID(ctx context.Context, openID string) (*User, error) {
	var user User
	query := `SELECT * FROM users WHERE openid = ?`
	err := r.db.GetContext(ctx, &user, query, openID)
	if err != nil {
		if err == sql.ErrNoRows {
			return nil, nil // User not found, but not an error
		}
		return nil, fmt.Errorf("failed to find user: %w", err)
	}
	return &user, nil
}

// Create creates a new user
func (r *UserRepository) Create(ctx context.Context, user *User) error {
	query := `
		INSERT INTO users (id, openid, session_key, created_at, updated_at)
		VALUES (?, ?, ?, ?, ?)
	`
	now := time.Now()
	user.CreatedAt = now
	user.UpdatedAt = now

	_, err := r.db.ExecContext(
		ctx,
		query,
		user.ID,
		user.OpenID,
		user.SessionKey,
		user.CreatedAt,
		user.UpdatedAt,
	)
	if err != nil {
		return fmt.Errorf("failed to create user: %w", err)
	}
	return nil
}

// Update updates an existing user
func (r *UserRepository) Update(ctx context.Context, user *User) error {
	query := `
		UPDATE users
		SET session_key = ?, updated_at = ?
		WHERE id = ?
	`
	user.UpdatedAt = time.Now()

	_, err := r.db.ExecContext(
		ctx,
		query,
		user.SessionKey,
		user.UpdatedAt,
		user.ID,
	)
	if err != nil {
		return fmt.Errorf("failed to update user: %w", err)
	}
	return nil
}

// Delete deletes a user
func (r *UserRepository) Delete(ctx context.Context, id string) error {
	query := `DELETE FROM users WHERE id = ?`
	_, err := r.db.ExecContext(ctx, query, id)
	if err != nil {
		return fmt.Errorf("failed to delete user: %w", err)
	}
	return nil
}