const Database = require('better-sqlite3');
import path from 'path';
import fs from 'fs';

const dbPath = path.join(__dirname, '../data/invicanvas.db');
const dbDir = path.dirname(dbPath);

if (!fs.existsSync(dbDir)) {
  fs.mkdirSync(dbDir, { recursive: true });
}

export const db = new Database(dbPath);

db.pragma('journal_mode = WAL');

db.exec(`
  CREATE TABLE IF NOT EXISTS users (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    github_id TEXT UNIQUE,
    username TEXT NOT NULL,
    display_name TEXT,
    avatar_url TEXT,
    email TEXT,
    created_at DATETIME DEFAULT CURRENT_TIMESTAMP
  );

  CREATE TABLE IF NOT EXISTS pixels (
    x INTEGER NOT NULL,
    y INTEGER NOT NULL,
    color TEXT NOT NULL,
    updated_at DATETIME DEFAULT CURRENT_TIMESTAMP,
    PRIMARY KEY (x, y)
  );

  CREATE INDEX IF NOT EXISTS idx_pixels_updated ON pixels(updated_at);
`);

export function generateUserId(): string {
  return `user_${Date.now()}_${Math.random().toString(36).substr(2, 9)}`;
}

export function upsertPixels(pixels: { x: number; y: number; color: string }[]): void {
  const stmt = db.prepare(
    'INSERT OR REPLACE INTO pixels (x, y, color, updated_at) VALUES (?, ?, ?, CURRENT_TIMESTAMP)'
  );
  
  const transaction = db.transaction((pixels: any[]) => {
    for (const pixel of pixels) {
      stmt.run(pixel.x, pixel.y, pixel.color);
    }
  });
  
  transaction(pixels);
}

export function getAllPixels(): { x: number; y: number; color: string }[] {
  const stmt = db.prepare('SELECT x, y, color FROM pixels ORDER BY x, y');
  return stmt.all() as { x: number; y: number; color: string }[];
}