<?php

function DatabaseCreateTable($table, $columnsDefinition) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $sql = "CREATE TABLE IF NOT EXISTS `$table` ($columnsDefinition)";
    $stmt = $conn->prepare($sql);

    if (!$stmt) {
        die("Fehler beim Prepare: " . $conn->error);
    }

    if (!$stmt->execute()) {
        die("Fehler beim Execute: " . $stmt->error);
    }

    return true;
}

function DatabaseShowTables() {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $tablesResult = $conn->query("SHOW TABLES");
    if (!$tablesResult) {
        die("Fehler beim Laden der Tabellen: " . $conn->error);
    }

    $tables = [];

    while ($tableRow = $tablesResult->fetch_array()) {
        $tables[] = $tableRow[0];
    }

    return $tables;
}

function DatabaseShowTableStructure($table) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $stmt = $conn->prepare("SHOW COLUMNS FROM `$table`");
    if (!$stmt) {
        die("Fehler beim Prepare: " . $conn->error);
    }

    if (!$stmt->execute()) {
        die("Fehler beim Execute: " . $stmt->error);
    }

    $result = $stmt->get_result();

    $columns = [];

    while ($column = $result->fetch_assoc()) {
        $columns[] = [
            "Field"   => $column["Field"],
            "Type"    => $column["Type"],
            "Null"    => $column["Null"],
            "Key"     => $column["Key"],
            "Default" => $column["Default"],
            "Extra"   => $column["Extra"]
        ];
    }

    return $columns;
}

function DatabaseShow($table, $columns = "*", $where = "", ...$values) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $sql = "SELECT $columns FROM `$table`";

    if (!empty($where)) {
        $sql .= " WHERE $where";
    }

    $stmt = $conn->prepare($sql);

    if (!$stmt) {
        die("Fehler beim Prepare: " . $conn->error);
    }

    if (!$stmt->execute($values)) {
        die("Fehler beim Execute: " . $stmt->error);
    }

    $result = $stmt->get_result();
    return $result->fetch_all(MYSQLI_ASSOC);
}


function DatabaseInsert($table, $columns, ...$values) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();
    
    $placeholders = rtrim(str_repeat("?,", count($values)), ",");
    $sql = "INSERT INTO `$table` ($columns) VALUES ($placeholders)";
    $stmt = $conn->prepare($sql);

    if (!$stmt) {
        die("Fehler beim Prepare: " . $conn->error);
    }

    if (!$stmt->execute($values)) {
        die("Fehler beim Execute: " . $stmt->error);
    }
    
    return true;
}

function DatabaseDelete($table, $where, ...$values) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $sql = "DELETE FROM `$table` WHERE $where";
    $stmt = $conn->prepare($sql);

    if (!$stmt) {
        die("Fehler beim Prepare: " . $conn->error);
    }

    if (!$stmt->execute($values)) {
        die("Fehler beim Execute: " . $stmt->error);
    }

    return true;
}

function DatabaseUpdate($table, $set, $where, ...$values) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $sql = "UPDATE `$table` SET $set WHERE $where";
    $stmt = $conn->prepare($sql);

    if (!$stmt) {
        die("Fehler beim Prepare: " . $conn->error);
    }

    if (!$stmt->execute($values)) {
        die("Fehler beim Execute: " . $stmt->error);
    }

    return true;
}

function getFKValue($conn, $table, $key, $value, $id, &$cache) {
    if ($id === null) return null;

    $cacheKey = $table . "_" . $id;

    if (isset($cache[$cacheKey])) {
        return $cache[$cacheKey];
    }

    $stmt = $conn->prepare("SELECT `$value` FROM `$table` WHERE `$key` = ? LIMIT 1");
    if (!$stmt) {
        die("FK Prepare Fehler: " . $conn->error);
    }

    $stmt->bind_param("i", $id);
    $stmt->execute();

    $result = $stmt->get_result()->fetch_assoc();
    $valueResult = $result[$value] ?? null;

    $cache[$cacheKey] = $valueResult;

    return $valueResult;
}

function DatabaseShowWithFK($table, $fkMap = [], $columns = "*", $where = "", ...$values) {
    include_once 'DatabaseConnect.php';
    $conn = db_connect();

    $cache = [];

    $select = is_array($columns) ? implode(", ", $columns) : $columns;

    $sql = "SELECT $select FROM `$table`";
    if (!empty($where)) {
        $sql .= " WHERE $where";
    }

    $stmt = $conn->prepare($sql);
    if (!$stmt) die("Fehler beim Prepare: " . $conn->error);

    if (!empty($values)) {
        $stmt->execute($values);
    } else {
        $stmt->execute();
    }

    $result = $stmt->get_result();
    if (!$result) die("Fehler beim get_result: " . $conn->error);

    $rows = $result->fetch_all(MYSQLI_ASSOC);

    foreach ($rows as &$row) {
        foreach ($fkMap as $fkColumn => $fkInfo) {

            if (!isset($row[$fkColumn]) || $row[$fkColumn] === null) {
                continue;
            }

            $row[$fkColumn] = getFKValue(
                $conn,
                $fkInfo['table'],
                $fkInfo['key'],
                $fkInfo['value'],
                $row[$fkColumn],
                $cache
            );
        }
    }

    return [
        "rows" => $rows
    ];
}

$Berufsschulberichte = [
    "FACH_S1" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S1" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S1" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S2" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S2" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S2" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S3" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S3" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S3" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S4" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S4" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S4" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S5" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S5" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S5" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S6" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S6" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S6" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S7" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S7" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S7" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
    
    "FACH_S8" => ["table" => "Fach", "key" => "ID", "value" => "Fach"],
    "LEHRER_S8" => ["table" => "Lehrer", "key" => "ID", "value" => "NAME"],
    "RAUM_S8" => ["table" => "Raum", "key" => "ID", "value" => "Raum_NR"],
];

$Stundenplan = [
    "MO" => ["table" => "Fach", "key"   => "ID", "value" => "Fach"],
    "DI" => ["table" => "Fach", "key"   => "ID", "value" => "Fach"],
    "MI" => ["table" => "Fach", "key"   => "ID", "value" => "Fach"],
    "DO" => ["table" => "Fach", "key"   => "ID", "value" => "Fach"],
    "FR" => ["table" => "Fach", "key"   => "ID", "value" => "Fach"],
];

$Berechtigungen = [
    "BENUTZER_ID"   => ["table" => "Benutzer",          "key" => "ID", "value" => "NAME"],
    "SEITEN_ID"     => ["table" => "Backend_Seiten",    "key" => "ID", "value" => "DATEINAME"]
];