package database

import (
	"context"
	"fmt"
	"os"
	"time"

	"5803025048/W04/internal/auth"
	"github.com/google/uuid"
	"github.com/jackc/pgx/v5"
)

// Connect membuat koneksi ke PostgreSQL menggunakan env vars individual
func Connect() (*pgx.Conn, error) {
	host := getEnvOrDefault("DB_HOST", "localhost")
	port := getEnvOrDefault("DB_PORT", "5432")
	user := os.Getenv("DB_USER")
	password := os.Getenv("DB_PASSWORD")
	dbname := os.Getenv("DB_NAME")
	sslmode := getEnvOrDefault("DB_SSLMODE", "disable")

	connStr := fmt.Sprintf(
		"host=%s port=%s user=%s password=%s dbname=%s sslmode=%s",
		host, port, user, password, dbname, sslmode,
	)

	conn, err := pgx.Connect(context.Background(), connStr)
	if err != nil {
		return nil, fmt.Errorf("unable to connect to database: %v", err)
	}
	return conn, nil
}

// CreateTables membuat tabel users, sessions, dan snippets jika belum ada
func CreateTables(conn *pgx.Conn) error {
	queries := []string{
		`CREATE TABLE IF NOT EXISTS users (
			id            TEXT PRIMARY KEY,
			username      TEXT UNIQUE NOT NULL,
			password_hash TEXT NOT NULL
		)`,
		`CREATE TABLE IF NOT EXISTS sessions (
			token      TEXT PRIMARY KEY,
			user_id    TEXT NOT NULL REFERENCES users(id) ON DELETE CASCADE,
			created_at TIMESTAMPTZ NOT NULL DEFAULT NOW()
		)`,
		`CREATE TABLE IF NOT EXISTS snippets (
			id      TEXT PRIMARY KEY,
			title   TEXT NOT NULL,
			content TEXT NOT NULL,
			user_id TEXT NOT NULL REFERENCES users(id) ON DELETE CASCADE
		)`,
	}

	for _, q := range queries {
		_, err := conn.Exec(context.Background(), q)
		if err != nil {
			return fmt.Errorf("failed to create table: %v", err)
		}
	}

	// Otomatis masukkan data sample 2 user & session
	if err := SeedSampleData(conn); err != nil {
		fmt.Fprintf(os.Stderr, "Warning: failed to seed sample data: %v\n", err)
	}

	return nil
}

// SeedSampleData memasukkan data sample 2 user dan session ke database dan mencetak infonya langsung ke konsol VS Code
func SeedSampleData(conn *pgx.Conn) error {
	ctx := context.Background()

	samples := []struct {
		username string
		password string
	}{
		{username: "zagar", password: "password123"},
		{username: "zagarnashrullah", password: "password12345"},
		{username: "jiminyu", password: "password12345678"},
		{username: "yj", password: "password12345678910"},
	}

	fmt.Println("✅ INSERT DATA SAMPLE KE DATABASE (lebih dari 2 USERS):")

	for i, s := range samples {
		userID := uuid.New().String()
		hash, err := auth.HashPassword(s.password)
		if err != nil {
			return fmt.Errorf("failed to hash password for %s: %w", s.username, err)
		}

		err = conn.QueryRow(ctx,
			"INSERT INTO users (id, username, password_hash) VALUES ($1, $2, $3) ON CONFLICT (username) DO UPDATE SET password_hash = EXCLUDED.password_hash RETURNING id",
			userID, s.username, hash,
		).Scan(&userID)
		if err != nil {
			return fmt.Errorf("failed to insert user %s: %w", s.username, err)
		}

		token, err := auth.GenerateToken()
		if err != nil {
			return fmt.Errorf("failed to generate session token for %s: %w", s.username, err)
		}

		_, err = conn.Exec(ctx,
			"INSERT INTO sessions (token, user_id, created_at) VALUES ($1, $2, $3)",
			token, userID, time.Now(),
		)
		if err != nil {
			return fmt.Errorf("failed to insert session for %s: %w", s.username, err)
		}

		fmt.Printf("\n--- [User %d: %s] ---\n", i+1, s.username)
		fmt.Printf("   User ID       : %s\n", userID)
		fmt.Printf("   Username      : %s\n", s.username)
		fmt.Printf("   Password Plain: %s\n", s.password)
		fmt.Printf("   Password Hash : %s\n", hash)
		fmt.Printf("   Session Token : %s\n", token)
	}

	return nil
}

func getEnvOrDefault(key, defaultVal string) string {
	if val := os.Getenv(key); val != "" {
		return val
	}
	return defaultVal
}