<?php
header("Content-Type:application/json");

$host="srv-sql.kmpr.local";
$user="duplicates";
$password="2rqyc\$Tnl0m00l4h";
$database="image_duplicates";
$table="possible_duplicates";

$db = new PDO("mysql:host=$host;dbname=$database", $user, $password);

if (isset($_GET['insertDuplicate'])) {
	$data = json_decode(file_get_contents('php://input'), true);
	$file1 = trim($data['file1'] ?? '');
	$file2 = trim($data['file2'] ?? '');
	if ($file1 != "" || $file2 != ""){
		if(!pairExists($file1, $file2)) {
			try {
				$db->query("INSERT INTO possible_duplicates (file1,file2) VALUES ('$file1', '$file2');");
				response(200, "Duplicate pair successfully written to database.");
			} catch (PDOException $e) {
				response(999, "Database Error: " . $e->getMessage());
				die();
			}
		} else {
			response(907, "Error: Duplicate pair already exists in database!");
		}
	} else {
		response(901, "Error: You have to provide file1 and file2 as possible duplicates!");
	}
} else if (isset($_GET['getDuplicates'])) {
	$data = json_decode(file_get_contents('php://input'), true);
	$amount = trim($data['amount'] ?? '');
	if ($amount != "") {
		if (ctype_digit($amount)) {
			try {
				$res = $db->query("SELECT * FROM possible_duplicates WHERE id NOT IN (SELECT pd_id FROM no_duplicates) LIMIT $amount;")->fetchAll(PDO::FETCH_ASSOC);
				response(200, "Database query successful.", $res);
			} catch (PDOException $e) {
				response(999, "Database Error: " . $e->getMessage());
				die();
			}
		} else {
			response(905, "Error: Variable 'amount' has to be an integer value!");
		}
	} else {
		response(904, "You have to provide 'amount' to tell how much possible duplicates you want to recieve!");
	}
} else if (isset($_GET['noDuplicate'])) {
	$data = json_decode(file_get_contents('php://input'), true);
	$duplicateId = trim($data['duplicateId'] ?? '');
	if ($duplicateId != "") {
		if (ctype_digit($duplicateId)) {
			try {
				$st = $db->prepare("INSERT INTO no_duplicates (pd_id) SELECT id FROM possible_duplicates WHERE id = ?;");
				$st->execute(array($duplicateId));
				if ($st->rowCount()) {
					response(200, "Pair successfully marked as non-duplicate.");
				} else {
					response(940, "Error: duplicateId not found in database or pair already marked as non-duplicate.");	
				}
			} catch (PDOException $e) {
				response(999, "Database Error: " . $e->getMessage());
				die();
			}
		} else {
			response(906, "Error: Variable 'duplicateId' has to be an integer value!");
		}
	} else {
		response(902, "Error: You have to provide 'duplicateId' to mark a file pair as non-duplicate!");
	}
} else if (isset($_GET['undoDuplicate'])) {
	$data = json_decode(file_get_contents('php://input'), true);
	$duplicateId = trim($data['duplicateId'] ?? '');
	if ($duplicateId != "") {
		if (ctype_digit($duplicateId)) {
			try {
				$st = $db->prepare("DELETE FROM no_duplicates WHERE pd_id = ?;");
				$st->execute(array($duplicateId));
				if ($st->rowCount()) {
					response(200, "Removed successfully the mark as non-duplicate.");
				} else {
					response(940, "Error: duplicateId not found in database or pair is not marked as non-duplicate.");	
				}
			} catch (PDOException $e) {
				response(999, "Database Error: " . $e->getMessage());
				die();
			}
		} else {
			response(906, "Error: Variable 'duplicateId' has to be an integer value!");
		}
	} else {
		response(902, "Error: You have to provide 'duplicateId' to mark a file pair as non-duplicate!");
	}

} else if(isset($_GET['isDuplicate'])) {
	$data = json_decode(file_get_contents('php://input'), true);
	$duplicateId = trim($data['duplicateId'] ?? '');
	if ($duplicateId != "") {
		if (ctype_digit($duplicateId)) {
			try {
				$st = $db->prepare("DELETE FROM possible_duplicates WHERE id = ?;");
				$st->execute(array($duplicateId));
				if ($st->rowCount()) {
					response(200, "Duplicate pair successfully removed from database.");
				} else {
					response(940, "Error: duplicateId not found in database.");	
				}
			} catch (PDOException $e) {
				response(999, "Database Error: " . $e->getMessage());
				die();
			}
		} else {
			response(906, "Error: Variable 'duplicateId' has to be an integer value!");
		}
	} else {
		response(903, "Error: You have to provide 'duplicateId' to mark a file pair as duplicate!");
	}
} else if(isset($_GET['totalDuplicates'])) {
	try {
		$res = $db->query("SELECT COUNT(id) AS totalDuplicates FROM possible_duplicates WHERE id NOT IN (SELECT pd_id FROM no_duplicates);")->fetchColumn(0);
		response(200, "Database query successful.", NULL, $res);
	} catch (PDOException $e) {
		response(999, "Database Error: " . $e->getMessage());
		die();
	}
} else if(isset($_GET['test'])) {
	try {
		$res = $db->query("select 'MySQL is working.' as Display;");
		response(200, "API is working properly.", NULL, NULL);
	} catch (PDOException $e) {
		response(999, "Database Error: " . $e->getMessage());
		die();
	}
} else {
	response(400, "Error: Invalid Request");
}

function response ($response_code, $response_desc, $payload=NULL, $totalDuplicates=NULL) {
	$response['response_code'] = $response_code;
	$response['response_desc'] = $response_desc;
	$response['payload'] = $payload;
	$response['totalDuplicates'] = $totalDuplicates;
	$json_response = json_encode($response);
	echo $json_response;
}

function pairExists($file1, $file2) {
	try {
		global $db;
		$rows = $db->query("SELECT COUNT(id) FROM possible_duplicates WHERE (file1 LIKE '$file1' AND file2 LIKE '$file2') OR (file1 LIKE '$file2' AND file2 LIKE '$file1');")->fetchColumn();
		if ($rows > 0) {
			return true;
		} else {
			return false;
		}
	} catch (PDOException $e) {
    		response(999, "Database Error: " . $e->getMessage());
    		die();
	}
}
?>