<?php

declare(strict_types=1);

require __DIR__ . '/db.php';
require __DIR__ . '/helpers.php';

const SETTINGS_KEY = 'pos_settings';

function ensure_settings_table(PDO $pdo): void
{
    $pdo->exec(
        'CREATE TABLE IF NOT EXISTS settings (
            setting_key VARCHAR(100) PRIMARY KEY,
            setting_value JSON NOT NULL,
            updated_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP
        )'
    );
}

function default_pos_settings(): array
{
    return [
        'groceryTaxRate' => 2,
        'quickButtons' => [
            [
                'id' => 'unleaded',
                'label' => 'Unleaded',
                'shortLabel' => 'GAS',
                'taxable' => true,
                'reportCategory' => 'Unleaded',
            ],
            [
                'id' => 'unleaded-plus',
                'label' => 'Unleaded Plus',
                'shortLabel' => 'GAS+',
                'taxable' => true,
                'reportCategory' => 'Unleaded Plus',
            ],
            [
                'id' => 'diesel',
                'label' => 'Diesel',
                'shortLabel' => 'DSL',
                'taxable' => true,
                'reportCategory' => 'Diesel',
            ],
            [
                'id' => 'off-road-diesel',
                'label' => 'Off Road Diesel',
                'shortLabel' => 'ORD',
                'taxable' => false,
                'reportCategory' => 'Off Road Diesel',
            ],
            [
                'id' => 'hardware',
                'label' => 'Hardware',
                'shortLabel' => 'HDW',
                'taxable' => true,
                'reportCategory' => 'Hardware',
            ],
            [
                'id' => 'oil',
                'label' => 'Oil',
                'shortLabel' => 'OIL',
                'taxable' => true,
                'reportCategory' => 'Oil',
            ],
        ],
    ];
}

if ($_SERVER['REQUEST_METHOD'] === 'GET') {
    $pdo = db();
    ensure_settings_table($pdo);
    $stmt = $pdo->prepare(
        'SELECT setting_value FROM settings WHERE setting_key = :setting_key'
    );
    $stmt->execute(['setting_key' => SETTINGS_KEY]);
    $row = $stmt->fetch();

    if (!$row) {
        json_response(default_pos_settings());
    }

    $decoded = json_decode((string) $row['setting_value'], true);
    if (!is_array($decoded)) {
        json_response(default_pos_settings());
    }

    json_response($decoded);
}

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    json_response(['error' => 'Method not allowed'], 405);
}

$payload = read_json_body();
if (
    !isset($payload['groceryTaxRate'], $payload['quickButtons']) ||
    !is_array($payload['quickButtons'])
) {
    json_response(['error' => 'Missing settings payload'], 400);
}

$pdo = db();
ensure_settings_table($pdo);
$stmt = $pdo->prepare(
    'INSERT INTO settings (setting_key, setting_value)
     VALUES (:setting_key, :setting_value)
     ON DUPLICATE KEY UPDATE setting_value = VALUES(setting_value)'
);
$stmt->execute([
    'setting_key' => SETTINGS_KEY,
    'setting_value' => json_encode($payload, JSON_UNESCAPED_UNICODE),
]);

json_response(['ok' => true]);