<?php
session_start();
include_once('../../config/db_config.php');

// Check if admin is logged in
if (!isset($_SESSION['user_id']) || ($_SESSION['role'] !== 'admin' && $_SESSION['role'] !== 'director')) {
    echo json_encode([
        'success' => false,
        'message' => 'Unauthorized access'
    ]);
    exit();
}

// Validate request
if ($_SERVER['REQUEST_METHOD'] !== 'GET' || !isset($_GET['document_id']) || empty($_GET['document_id'])) {
    echo json_encode([
        'success' => false,
        'message' => 'Invalid request parameters'
    ]);
    exit();
}

$documentId = (int)$_GET['document_id'];

try {
    // Get document details with student information
    $query = "
        SELECT 
            d.id,
            d.user_id,
            d.document_type,
            d.document_path,
            d.upload_date,
            d.status,
            d.admin_notes,
            u.first_name,
            u.last_name,
            u.email
        FROM 
            student_documents d
        JOIN 
            users u ON d.user_id = u.id
        WHERE 
            d.id = ?
    ";
    
    $stmt = $conn->prepare($query);
    $stmt->bind_param("i", $documentId);
    $stmt->execute();
    $result = $stmt->get_result();
    
    if ($result->num_rows === 0) {
        echo json_encode([
            'success' => false,
            'message' => 'Document not found'
        ]);
        exit();
    }
    
    $document = $result->fetch_assoc();
    
    // Format document for response
    $documentTypes = [
        'id_proof' => 'ID Proof',
        'address_proof' => 'Address Proof',
        'educational_certificate' => 'Educational Certificate',
        'photograph' => 'Passport Size Photo',
        'other' => 'Other Document'
    ];
    
    // Format the document status
    $statusBadge = '';
    switch ($document['status']) {
        case 'pending':
            $statusBadge = '<span class="badge bg-warning text-dark">Pending</span>';
            break;
        case 'verified':
            $statusBadge = '<span class="badge bg-success">Verified</span>';
            break;
        case 'rejected':
            $statusBadge = '<span class="badge bg-danger">Rejected</span>';
            break;
        default:
            $statusBadge = '<span class="badge bg-secondary">Unknown</span>';
    }
    
    // Format the upload date
    $uploadDate = date('M d, Y', strtotime($document['upload_date']));
    
    // Format the document type
    $documentType = isset($documentTypes[$document['document_type']]) 
        ? $documentTypes[$document['document_type']] 
        : ucfirst(str_replace('_', ' ', $document['document_type']));
    
    // Format student name
    $studentName = $document['first_name'] . ' ' . $document['last_name'];
    
    // Fix path if needed
    $filePath = $document['document_path'];
    if (strpos($filePath, '../') === 0) {
        $filePath = substr($filePath, 3);
    }
    
    $formattedDocument = [
        'id' => $document['id'],
        'user_id' => $document['user_id'],
        'document_type' => $document['document_type'],
        'document_type_display' => $documentType,
        'file_path' => $filePath,
        'upload_date' => $uploadDate,
        'status' => $document['status'],
        'status_badge' => $statusBadge,
        'admin_notes' => $document['admin_notes'],
        'student_name' => $studentName,
        'student_email' => $document['email']
    ];
    
    echo json_encode([
        'success' => true,
        'document' => $formattedDocument
    ]);
    
} catch (Exception $e) {
    echo json_encode([
        'success' => false,
        'message' => 'Error: ' . $e->getMessage()
    ]);
}
?>