Назначение Система бронирования Слоты

Я пытаюсь создать систему бронирования встреч, в которой все остальное работает, за исключением временных интервалов встреч, в которых, например, если встреча назначена на 11:30 и длится час (12:30), никто не может забронировать или назначить встречу в эти времена.
Я преобразовал время начала и окончания ввода в Unix-время, а также преобразовал время, уже установленное в базе данных, но это меня не подводит.

Я попытался сравнить время окончания между двумя временами, установленными пользователем, и временем окончания пользователя между двумя временами уже в базе данных.
Мой код:

 if ($length == "1 Hour"){
$edittime = $time;
$timeedit = strtotime($edittime)+3600;
$endtime = date('h:i:s', strftime($timeedit));
} elseif ($length == "1 Hour 30 Minutes") {
$edittime = $time;
$timeedit = strtotime($edittime)+5400;
$endtime = date('h:i:s', strftime($timeedit));
} elseif ($length == "2 Hour") {
$edittime = $time;
$timeedit = strtotime($edittime)+7200;
$endtime = date('h:i:s', strftime($timeedit));
} else {
header("location:Cancel.php");
}
/*Comparison of the start and end times, as well as the user input time.*/
$querysql = "SELECT Time FROM $tablename WHERE Time <= '$endtime' AND Date = '$date'";
$queryresult = mysqli_query($connection, $querysql);
/*Validate the query.*/
if (! $queryresult) {
echo ("Could not retrieve the sql data : " . mysqli_error($connection) . " " . mysqli_errno($connection));
}

/*Array to collect data from the sql query, to compare against the appointment times the user entered.*/
$count = 0;
$starttime = $time;
$secondtime = strtotime($starttime);
$existapp[$count] = mysqli_fetch_array($queryresult, MYSQLI_NUM);
while ($existapp[$count] <> "") {
$temp = $existapp[$count];
$acquireddata = $temp[$count];
$appsec = strtotime($acquireddata);
if ($length == "1 Hour") {
$existstart = $appsec;
$existedit = $existstart + 3600;
$existend = date('h:i:s', strftime($existedit));
} elseif ($length == "1 Hour 30 Minutes") {
$existstart = $appsec;
$existedit = $existstart + 3600;
$existend = date('h:i:s', strftime($existedit));
} elseif ($length == "2 Hour") {
$existstart = $appsec;
$existedit = $existstart + 3600;
$existend = date('h:i:s', strftime($existedit));
}
/*$timeedit = end time*/
/*$secondtime = start time*/
/*$existededit = exisiting appointment*/

if ($timeedit <= $existedit and $timeedit >= $existstart) {
header("location:Cancel.php");
}
$count = $count + 1;
}

Если вам нужен весь файл, тогда просто напишите мне.

Я без конца искал это, и после проверки времени Unix, это должно работать! Но это не так! ):

<?php
/*Checks if user is logged in, else redirect to home.*/
session_start();
if(! $_SESSION['Username']) {
header("location:Index.php");
}
/*Sets variables as the login to the database, as well as tables of interest.*/
$servername = "";
$username = "";
$password = "";
$dbname = "";
$tablename = "appointmentinformation";
$tablenamed = "clientinformation";

/*Connect to the database server and the database.*/
$connection = mysqli_connect("$servername", "$username", "$password", "$dbname") or die("Could not connect to the database");
if (mysqli_connect_errno()) {
echo "Failed to connect to MySQL: " . mysqli_connect_error();
}
/*Retrieve the username from the current session.*/
$clientusername = $_SESSION['Username'];
/*Retrieve the ClientID of interest from a table, with a parameter of the username. Limit the amount of results to one row (one result).*/
$sql = "SELECT ClientID FROM $tablenamed WHERE Username = '$clientusername' LIMIT 1";
/*Validate the query.*/
$results = mysqli_query($connection, $sql);
if (! $results) {
echo ("Could not select the data : " . mysql_error());
} else {
$datarows = mysqli_fetch_row($results);
$clientid = $datarows[0];
}
/*Retrieve user input.*/
$date = $_POST["date"];
$time = $_POST["time"];
$length = $_POST["length"];

/*Format date*/
$date = str_replace('/', '-', $date);

/*Protection from SQL injection attacks.*/
$date = stripslashes($date);
$time = stripslashes($time);
$length = stripslashes($length);
$date = mysqli_real_escape_string($connection, $date);
$time = mysqli_real_escape_string($connection, $time);
$length = mysqli_real_escape_string($connection, $length);

if ($length == "1 Hour"){
$edittime = $time;
$timeedit = strtotime($edittime)+3600;
} elseif ($length == "1 Hour 30 Minutes") {
$edittime = $time;
$timeedit = strtotime($edittime)+5400;
} elseif ($length == "2 Hour") {
$edittime = $time;
$timeedit = strtotime($edittime)+7200;
} else {
header("location:Cancel.php");
}
/*Comparison of the start and end times, as well as the user input time.*/
$querysql = "SELECT Time FROM $tablename WHERE Time <= '$endtime' AND Date = '$date'";
$queryresult = mysqli_query($connection, $querysql);
/*Validate the query.*/
if (! $queryresult) {
echo ("Could not retrieve the sql data : " . mysqli_error($connection) . " " . mysqli_errno($connection));
}

/*Array to collect data from the sql query, to compare against the appointment times the user entered.*/
$count = 0;
$starttime = $time;
$secondtime = strtotime($starttime);
$existapp[$count] = mysqli_fetch_array($queryresult, MYSQLI_NUM);
while ($existapp[$count] <> "") {
$temp = $existapp[$count];
$acquireddata = $temp[$count];
$appsec = strtotime($acquireddata);
if ($length == "1 Hour") {
$existstart = $appsec;
$existedit = $existstart + 3600;
} elseif ($length == "1 Hour 30 Minutes") {
$existstart = $appsec;
$existedit = $existstart + 3600;
} elseif ($length == "2 Hour") {
$existstart = $appsec;
$existedit = $existstart + 3600;
}
/*$timeedit = end time*/
/*$secondtime = start time*/
/*$existededit = exisiting appointment*/

if ($timeedit <= $existedit and $timeedit >= $existstart) {
header("location:Cancel.php");
}
$count = $count + 1;
}

/*SELECT query to retrieve data from the database. A complex query due to two parameters.*/
$sqlquery = "SELECT * FROM $tablename WHERE Date = '$date' AND Time = '$time'";
$sqlresult = mysqli_query($connection, $sqlquery);
/*Validate the query.*/
if (! $sqlresult) {
echo ("Could not retrieve the sql data : " . mysqli_error($connection) . " " . mysqli_errno($connection));
}
$rows = mysqli_fetch_row($sqlresult);
$date1 = $rows[3];
$time1 = $rows[4];

/*Compare the date and times and validate.*/
if ($date === $date1 && $time = $time1) {
echo("This date/time is taken!");
header("location:CreateAppointmentForm.php");
} else {
/*Insert the data into the database if validation passes.*/
$query = "INSERT INTO appointmentinformation (ClientID, Length, Date, Time) VALUES ('$clientid', '$length', '$date', '$time')";
$result = mysqli_query($connection, $query);
if ($result) {
header("Location:UserCP.php");
} else {
echo ("Could not insert data : " . mysqli_error($connection) . " " . mysqli_errno($connection));
}
}

?>