<?php
require_once '../db/config.php';

header('Content-Type: application/json');

$id = $_GET['id'] ?? null;

if (!$id) {
    http_response_code(400);
    echo json_encode(['error' => 'Tax ID is required']);
    exit;
}

try {
    $pdo = db();

    $stmt = $pdo->prepare("SELECT id FROM taxes WHERE id = ?");
    $stmt->execute([$id]);
    if (!$stmt->fetch()) {
        http_response_code(404);
        echo json_encode(['error' => 'Tax not found']);
        exit;
    }

    // Check if the tax is being used in any sale
    $stmt = $pdo->prepare("SELECT id FROM sale_taxes WHERE tax_id = ?");
    $stmt->execute([$id]);
    if ($stmt->fetch()) {
        http_response_code(400);
        echo json_encode(['error' => 'Cannot delete tax because it is associated with existing sales.']);
        exit;
    }

    $stmt = $pdo->prepare("DELETE FROM taxes WHERE id = ?");
    $stmt->execute([$id]);

    echo json_encode(['success' => 'Tax deleted successfully']);

} catch (PDOException $e) {
    http_response_code(500);
    echo json_encode(['error' => 'Database error: ' . $e->getMessage()]);
}