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

// Ensure admin is logged in
if (!isset($_SESSION['user_id']) || !in_array('Admin', $_SESSION['user_roles'])) {
    header('Location: login.php');
    exit;
}

// Fetch all submissions with their answers
$stmt = db()->query("SELECT 
    s.id as submission_id, 
    s.name as submitter_name, 
    s.email as submitter_email, 
    s.created_at as submission_date, 
    sv.title as survey_title, 
    q.question_text, 
    a.answer_text 
FROM feedback_submissions s
JOIN surveys sv ON s.survey_id = sv.id
LEFT JOIN survey_answers a ON s.id = a.submission_id
LEFT JOIN survey_questions q ON a.question_id = q.id
ORDER BY s.created_at DESC, q.created_at ASC");

$results = $stmt->fetchAll(PDO::FETCH_ASSOC);

// Set headers for CSV download
header('Content-Type: text/csv; charset=utf-8');
header('Content-Disposition: attachment; filename=feedback_submissions_' . date('Y-m-d') . '.csv');

$output = fopen('php://output', 'w');

// Get all unique questions in order
$questions_stmt = db()->query("SELECT DISTINCT question_text FROM survey_questions ORDER BY created_at ASC");
$question_headers = $questions_stmt->fetchAll(PDO::FETCH_COLUMN);

// Output the column headings
$headers = array_merge(['Submission ID', 'Submitter', 'Email', 'Date', 'Survey'], $question_headers);
fputcsv($output, $headers);

// Process the results
$submissions = [];
foreach ($results as $row) {
    $submissions[$row['submission_id']]['details'] = [
        'submission_id' => $row['submission_id'],
        'submitter_name' => $row['submitter_name'],
        'submitter_email' => $row['submitter_email'],
        'submission_date' => $row['submission_date'],
        'survey_title' => $row['survey_title']
    ];
    $submissions[$row['submission_id']]['answers'][$row['question_text']] = $row['answer_text'];
}

// Write rows to CSV
foreach ($submissions as $submission_id => $data) {
    $row = $data['details'];
    foreach ($question_headers as $question) {
        $row[] = $data['answers'][$question] ?? '';
    }
    fputcsv($output, $row);
}

fclose($output);
exit;
?>