<?php
session_start();
require_once 'db/config.php';

// Redirect to login if not logged in
if (!isset($_SESSION['worker_id'])) {
    header('Location: login.php');
    exit();
}

$current_worker_id = $_SESSION['worker_id'];

if ($_SERVER['REQUEST_METHOD'] === 'POST') {
    $job_id = isset($_POST['job_id']) ? (int)$_POST['job_id'] : 0;
    $redirect_url = "job-detail.php?id=" . $job_id;

    if ($job_id === 0) {
        header("Location: jobs.php");
        exit();
    }

    try {
        $pdo = db();

        // 1. Check if the worker has already applied for this job
        $stmt_check = $pdo->prepare("SELECT id FROM job_applications WHERE job_id = :job_id AND worker_id = :worker_id");
        $stmt_check->bindParam(':job_id', $job_id, PDO::PARAM_INT);
        $stmt_check->bindParam(':worker_id', $current_worker_id, PDO::PARAM_INT);
        $stmt_check->execute();

        if ($stmt_check->fetch()) {
            // The worker has already applied
            header("Location: " . $redirect_url . "&application_status=error");
            exit();
        }

        // 2. Insert the new application
        $stmt_insert = $pdo->prepare("INSERT INTO job_applications (job_id, worker_id, status) VALUES (:job_id, :worker_id, 'pending')");
        $stmt_insert->bindParam(':job_id', $job_id, PDO::PARAM_INT);
        $stmt_insert->bindParam(':worker_id', $current_worker_id, PDO::PARAM_INT);
        
        if ($stmt_insert->execute()) {
            // Success
            header("Location: " . $redirect_url . "&application_status=success");
            exit();
        } else {
            // Failure
            header("Location: " . $redirect_url . "&application_status=error");
            exit();
        }

    } catch (PDOException $e) {
        // In a real app, log this error
        // error_log("Application error: " . $e->getMessage());
        header("Location: " . $redirect_url . "&application_status=error");
        exit();
    }

} else {
    // If accessed directly, redirect to the jobs page
    header("Location: jobs.php");
    exit();
}