<?php

// Apply the configured application timezone before anything formats or stores a
// date. config.php (loaded by the caller) supplies $time_zone.
require_once __DIR__ . '/assets/utils/timezone.php';

// db connection
/** overide native PDO function */
class database extends PDO {

	protected $query;

	public function __construct($dsn, $username = '', $password = '', $driver_options = array()) {
		parent::__construct($dsn, $username, $password, $driver_options);
		$this->setAttribute(PDO::ATTR_STATEMENT_CLASS, array('db_statement', array($this)));
	}

	public function last_query() {
		return $this->query;
	}

}

/** overide native PDO statement */
// for XSS protection
class db_statement extends PDOStatement {

	protected $pdo;

	protected function __construct($pdo) {
		$this->pdo = $pdo;
	}

	// double_encode is off so text that is loaded and saved again is not escaped
	// a second time (&quot; becoming &amp;quot;), and ENT_SUBSTITUTE keeps a value
	// with a broken byte sequence instead of silently storing an empty string.
	const ESCAPE_FLAGS = ENT_QUOTES | ENT_SUBSTITUTE;

	private static function escapeString(string $value): string {
		return htmlspecialchars($value, self::ESCAPE_FLAGS, 'UTF-8', false);
	}

	private static function escapeTree($node) {
		if (is_string($node)) return self::escapeString($node);
		if (!is_array($node)) return $node;
		$out = [];
		foreach ($node as $k => $v) {
			$out[is_string($k) ? self::escapeString($k) : $k] = self::escapeTree($v);
		}
		return $out;
	}

	public static function escapeValue(string $item): string {
		$first = $item[0] ?? '';
		if ($first === '{' || $first === '[') {
			$tree = json_decode($item, true);
			if (is_array($tree)) {
				$flags = JSON_PRESERVE_ZERO_FRACTION;
				// An empty {} must not come back as [].
				if ($tree === [] ) return $item;
				$encoded = json_encode(self::escapeTree($tree), $flags);
				if ($encoded !== false) return $encoded;
			}
		}
		return self::escapeString($item);
	}

	// PDOStatement::execute() is declared ?array $params = null : bool. This
	// override deliberately accepts a looser signature so callers may pass
	// positional arguments (see func_get_args() below), so the tightened return
	// type is opted out of rather than the call sites being changed.
	#[\ReturnTypeWillChange]
	public function execute($args = null) {
		// Perform logging here. PDO object is accessible
		// from $this->pdo.

		if (!is_array($args)) {
			$args = func_get_args();
		}else{
			// Cast all values to string before XSS processing.
			// json_decode requires a string — integers, booleans, and nulls
			// passed as bound parameters would otherwise cause a TypeError.
			// null is preserved as-is so PDO can bind NULL columns correctly.
			$args = array_map(fn($v) => is_null($v) ? null : (string)$v, $args);

			// Escape on the way in, to prevent stored XSS. Values holding a JSON
			// object/array are escaped string by string so they stay valid JSON.
			foreach($args as &$item){
				if (is_null($item)) continue;
				$item = self::escapeValue($item);
			}
			unset($item);
		}
		return parent::execute($args);
	}

}

//..................... PDO1 .....................//
$pdo1 = new database($db_type.':host='.$db_server.';dbname='.$db_database.';charset=utf8mb4', $db_user, $db_pass);
$pdo1->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

//..................... PDO2 .....................//
$pdo2 = new database($db_type2.':host='.$db_server2.';dbname='.$db_database2.';charset=utf8mb4', $db_user2, $db_pass2);
$pdo2->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);

// Pin both connections to the application timezone, so MySQL NOW() and PHP
// date() agree no matter how the database server itself is configured. Queries
// mix the two freely (rows written with NOW(), others with date()), and a
// mismatch shows up as timestamps hours away from the real clock.
foreach ([$pdo1, $pdo2] as $pdo_tz) {
	try {
		$pdo_tz->exec("SET time_zone = '" . APP_TIMEZONE_OFFSET . "'");
	} catch (PDOException $e) {
		// A server that refuses the offset keeps its own zone — no worse than
		// before this call existed, and not a reason to fail the request.
	}
}