<?php
declare(strict_types=1);

if (session_status() === PHP_SESSION_NONE) {
    session_start();
}

require_once __DIR__ . '/db/config.php';

function app_env(string $key, string $default = ''): string
{
    $serverValue = $_SERVER[$key] ?? null;
    if (is_string($serverValue) && $serverValue !== '') {
        return $serverValue;
    }

    $envValue = getenv($key);
    if (is_string($envValue) && $envValue !== '') {
        return $envValue;
    }

    return $default;
}

function project_name(): string
{
    return app_env('PROJECT_NAME', 'Fast LAMP Desk');
}

function project_description(): string
{
    return app_env('PROJECT_DESCRIPTION', 'Fast intake workflow with a simple admin dashboard for incoming project requests.');
}

function e(mixed $value): string
{
    return htmlspecialchars((string) $value, ENT_QUOTES, 'UTF-8');
}

function app_strlen(string $value): int
{
    return function_exists('mb_strlen') ? mb_strlen($value) : strlen($value);
}

function app_substr(string $value, int $start, int $length): string
{
    return function_exists('mb_substr') ? mb_substr($value, $start, $length) : substr($value, $start, $length);
}

function ensure_schema(): void
{
    static $done = false;
    if ($done) {
        return;
    }

    $sqlPath = __DIR__ . '/db/migrations/001_project_requests.sql';
    $sql = file_get_contents($sqlPath);
    if ($sql === false) {
        throw new RuntimeException('Unable to load schema migration.');
    }

    db()->exec($sql);
    $done = true;
}

function admin_email(): string
{
    return app_env('ADMIN_EMAIL', 'admin@local.test');
}

function admin_password(): string
{
    return app_env('ADMIN_PASSWORD', 'admin12345');
}

function using_default_admin_credentials(): bool
{
    return app_env('ADMIN_EMAIL', '') === '' || app_env('ADMIN_PASSWORD', '') === '';
}

function attempt_admin_login(string $email, string $password): bool
{
    if (!hash_equals(strtolower(admin_email()), strtolower(trim($email)))) {
        return false;
    }

    if (!hash_equals(admin_password(), $password)) {
        return false;
    }

    $_SESSION['admin_logged_in'] = true;
    $_SESSION['admin_email'] = admin_email();
    return true;
}

function logout_admin(): void
{
    $_SESSION = [];
    if (ini_get('session.use_cookies')) {
        $params = session_get_cookie_params();
        setcookie(session_name(), '', time() - 42000, $params['path'], $params['domain'], $params['secure'], $params['httponly']);
    }
    session_destroy();
}

function is_admin_logged_in(): bool
{
    return !empty($_SESSION['admin_logged_in']);
}

function require_admin(): void
{
    if (!is_admin_logged_in()) {
        set_flash('warning', 'Please sign in to access the dashboard.');
        header('Location: /login.php');
        exit;
    }
}

function set_flash(string $type, string $message): void
{
    $_SESSION['flash'] = ['type' => $type, 'message' => $message];
}

function get_flash(): ?array
{
    if (empty($_SESSION['flash']) || !is_array($_SESSION['flash'])) {
        return null;
    }

    $flash = $_SESSION['flash'];
    unset($_SESSION['flash']);
    return $flash;
}

function request_status_options(): array
{
    return [
        'new' => 'New',
        'reviewed' => 'Reviewed',
        'qualified' => 'Qualified',
        'closed' => 'Closed',
    ];
}

function request_type_options(): array
{
    return [
        'Internal tool' => 'Internal tool',
        'Admin dashboard' => 'Admin dashboard',
        'Client portal' => 'Client portal',
        'Marketing site' => 'Marketing site',
        'Other MVP' => 'Other MVP',
    ];
}

function timeline_options(): array
{
    return [
        'ASAP' => 'ASAP',
        '2-4 weeks' => '2–4 weeks',
        '1-2 months' => '1–2 months',
        'Flexible' => 'Flexible',
    ];
}

function budget_options(): array
{
    return [
        '<5k' => 'Under $5k',
        '5k-15k' => '$5k–$15k',
        '15k-50k' => '$15k–$50k',
        '50k+' => '$50k+',
        'Unknown' => 'Still defining',
    ];
}

function validate_request_input(array $input): array
{
    $errors = [];

    $name = trim((string) ($input['name'] ?? ''));
    $email = trim((string) ($input['email'] ?? ''));
    $company = trim((string) ($input['company'] ?? ''));
    $projectType = trim((string) ($input['project_type'] ?? ''));
    $timeline = trim((string) ($input['timeline'] ?? ''));
    $budget = trim((string) ($input['budget'] ?? ''));
    $details = trim((string) ($input['details'] ?? ''));

    if ($name === '' || app_strlen($name) < 2) {
        $errors['name'] = 'Enter a contact name.';
    }
    if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
        $errors['email'] = 'Enter a valid work email.';
    }
    if ($projectType === '' || !array_key_exists($projectType, request_type_options())) {
        $errors['project_type'] = 'Choose the type of MVP you need.';
    }
    if ($timeline === '' || !array_key_exists($timeline, timeline_options())) {
        $errors['timeline'] = 'Choose a timeline.';
    }
    if ($budget === '' || !array_key_exists($budget, budget_options())) {
        $errors['budget'] = 'Choose a budget range.';
    }
    if ($details === '' || app_strlen($details) < 20) {
        $errors['details'] = 'Share at least a short brief (20+ characters).';
    }

    return [
        'errors' => $errors,
        'data' => [
            'name' => app_substr($name, 0, 120),
            'email' => app_substr($email, 0, 190),
            'company' => app_substr($company, 0, 160),
            'project_type' => $projectType,
            'timeline' => $timeline,
            'budget' => $budget,
            'details' => app_substr($details, 0, 4000),
        ],
    ];
}

function create_request(array $input): int
{
    ensure_schema();
    $validated = validate_request_input($input);
    if ($validated['errors']) {
        throw new InvalidArgumentException('Request data is invalid.');
    }

    $data = $validated['data'];
    $stmt = db()->prepare('INSERT INTO project_requests (name, email, company, project_type, timeline, budget, details, status, created_at) VALUES (:name, :email, :company, :project_type, :timeline, :budget, :details, :status, UTC_TIMESTAMP())');
    $stmt->bindValue(':name', $data['name']);
    $stmt->bindValue(':email', $data['email']);
    $stmt->bindValue(':company', $data['company'] === '' ? null : $data['company'], $data['company'] === '' ? PDO::PARAM_NULL : PDO::PARAM_STR);
    $stmt->bindValue(':project_type', $data['project_type']);
    $stmt->bindValue(':timeline', $data['timeline']);
    $stmt->bindValue(':budget', $data['budget']);
    $stmt->bindValue(':details', $data['details']);
    $stmt->bindValue(':status', 'new');
    $stmt->execute();

    return (int) db()->lastInsertId();
}

function normalize_request_status(?string $status): ?string
{
    $status = trim((string) $status);
    if ($status === '' || !array_key_exists($status, request_status_options())) {
        return null;
    }

    return $status;
}

function normalize_request_search(string $search): string
{
    $search = preg_replace('/\s+/', ' ', trim($search));
    return app_substr((string) $search, 0, 120);
}

function request_search_reference_id(string $search): ?int
{
    $search = strtoupper(trim($search));
    if ($search === '') {
        return null;
    }

    if (preg_match('/^REQ-(\d{1,10})$/', $search, $matches) === 1) {
        return (int) $matches[1];
    }

    if (ctype_digit($search)) {
        return (int) $search;
    }

    return null;
}

function build_request_filters(?string $status = null, string $search = ''): array
{
    $where = [];
    $bindings = [];

    $status = normalize_request_status($status);
    if ($status !== null) {
        $where[] = 'status = :status';
        $bindings[':status'] = ['value' => $status, 'type' => PDO::PARAM_STR];
    }

    $search = normalize_request_search($search);
    if ($search !== '') {
        $searchConditions = [
            'name LIKE :search',
            'email LIKE :search',
            'company LIKE :search',
            'project_type LIKE :search',
            'details LIKE :search',
        ];
        $bindings[':search'] = ['value' => '%' . $search . '%', 'type' => PDO::PARAM_STR];

        $referenceId = request_search_reference_id($search);
        if ($referenceId !== null) {
            $searchConditions[] = 'id = :search_id';
            $bindings[':search_id'] = ['value' => $referenceId, 'type' => PDO::PARAM_INT];
        }

        $where[] = '(' . implode(' OR ', $searchConditions) . ')';
    }

    return [
        'where_sql' => $where ? ' WHERE ' . implode(' AND ', $where) : '',
        'bindings' => $bindings,
    ];
}

function bind_request_query_values(PDOStatement $stmt, array $bindings): void
{
    foreach ($bindings as $placeholder => $binding) {
        $stmt->bindValue($placeholder, $binding['value'], $binding['type']);
    }
}

function fetch_requests(?string $status = null, string $search = '', int $limit = 0, int $offset = 0): array
{
    ensure_schema();
    $filters = build_request_filters($status, $search);
    $sql = 'SELECT * FROM project_requests' . $filters['where_sql'] . ' ORDER BY created_at DESC, id DESC';

    if ($limit > 0) {
        $sql .= ' LIMIT :limit OFFSET :offset';
    }

    $stmt = db()->prepare($sql);
    bind_request_query_values($stmt, $filters['bindings']);

    if ($limit > 0) {
        $stmt->bindValue(':limit', $limit, PDO::PARAM_INT);
        $stmt->bindValue(':offset', max(0, $offset), PDO::PARAM_INT);
    }

    $stmt->execute();
    return $stmt->fetchAll();
}

function count_requests(?string $status = null, string $search = ''): int
{
    ensure_schema();
    $filters = build_request_filters($status, $search);
    $stmt = db()->prepare('SELECT COUNT(*) FROM project_requests' . $filters['where_sql']);
    bind_request_query_values($stmt, $filters['bindings']);
    $stmt->execute();
    return (int) $stmt->fetchColumn();
}

function fetch_request(int $id): ?array
{
    ensure_schema();
    $stmt = db()->prepare('SELECT * FROM project_requests WHERE id = :id LIMIT 1');
    $stmt->bindValue(':id', $id, PDO::PARAM_INT);
    $stmt->execute();
    $request = $stmt->fetch();

    return $request ?: null;
}

function update_request_status(int $id, string $status): bool
{
    ensure_schema();
    if (!array_key_exists($status, request_status_options())) {
        return false;
    }

    $stmt = db()->prepare('UPDATE project_requests SET status = :status WHERE id = :id');
    $stmt->bindValue(':status', $status);
    $stmt->bindValue(':id', $id, PDO::PARAM_INT);
    return $stmt->execute();
}

function dashboard_metrics(): array
{
    ensure_schema();
    $rows = db()->query('SELECT status, COUNT(*) AS count_rows FROM project_requests GROUP BY status')->fetchAll();
    $metrics = [
        'total' => 0,
        'new' => 0,
        'reviewed' => 0,
        'qualified' => 0,
        'closed' => 0,
    ];

    foreach ($rows as $row) {
        $status = (string) $row['status'];
        $count = (int) $row['count_rows'];
        $metrics['total'] += $count;
        if (array_key_exists($status, $metrics)) {
            $metrics[$status] = $count;
        }
    }

    return $metrics;
}

function request_reference(int $id): string
{
    return 'REQ-' . str_pad((string) $id, 4, '0', STR_PAD_LEFT);
}

function format_datetime(string $value): string
{
    try {
        $date = new DateTimeImmutable($value, new DateTimeZone('UTC'));
        return $date->format('M j, Y \a\t H:i') . ' UTC';
    } catch (Throwable $e) {
        return $value;
    }
}

function status_badge_class(string $status): string
{
    return match ($status) {
        'new' => 'text-bg-primary',
        'reviewed' => 'text-bg-secondary',
        'qualified' => 'text-bg-success',
        'closed' => 'text-bg-dark',
        default => 'text-bg-light',
    };
}

function active_nav(string $active, string $value): string
{
    return $active === $value ? 'active' : '';
}

function render_head(string $title, string $pageDescription = '', bool $noindex = false): void
{
    $projectDescription = $_SERVER['PROJECT_DESCRIPTION'] ?? getenv('PROJECT_DESCRIPTION') ?: '';
    $projectImageUrl = $_SERVER['PROJECT_IMAGE_URL'] ?? getenv('PROJECT_IMAGE_URL') ?: '';
    $description = $pageDescription !== '' ? $pageDescription : ($projectDescription ?: project_description());
    $assetVersion = (string) (filemtime(__DIR__ . '/assets/css/custom.css') ?: time());
    ?>
<!doctype html>
<html lang="en">
<head>
  <meta charset="utf-8" />
  <meta name="viewport" content="width=device-width, initial-scale=1" />
  <title><?= e($title) ?></title>
  <meta name="description" content="<?= e($description) ?>" />
<?php if ($projectDescription): ?>
  <meta property="og:description" content="<?= e($projectDescription) ?>" />
  <meta property="twitter:description" content="<?= e($projectDescription) ?>" />
<?php else: ?>
  <meta property="og:description" content="<?= e($description) ?>" />
  <meta property="twitter:description" content="<?= e($description) ?>" />
<?php endif; ?>
<?php if ($projectImageUrl): ?>
  <meta property="og:image" content="<?= e($projectImageUrl) ?>" />
  <meta property="twitter:image" content="<?= e($projectImageUrl) ?>" />
<?php endif; ?>
<?php if ($noindex): ?>
  <meta name="robots" content="noindex, nofollow" />
<?php endif; ?>
  <meta name="theme-color" content="#111827" />
  <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-QWTKZyjpPEjISv5WaRU9OFeRpok6YctnYmDr5pNlyT2bRjXh0JMhjY6hW+ALEwIH" crossorigin="anonymous">
  <link rel="stylesheet" href="/assets/css/custom.css?v=<?= e($assetVersion) ?>">
</head>
<body>
    <?php
}

function render_navbar(string $active = 'home'): void
{
    ?>
<nav class="navbar navbar-expand-lg border-bottom bg-white sticky-top app-navbar">
  <div class="container">
    <a class="navbar-brand fw-semibold" href="/">
      <span class="brand-mark">FL</span>
      <?= e(project_name()) ?>
    </a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#primaryNav" aria-controls="primaryNav" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="primaryNav">
      <ul class="navbar-nav ms-auto align-items-lg-center gap-lg-2">
        <li class="nav-item"><a class="nav-link <?= active_nav($active, 'home') ?>" href="/">Home</a></li>
        <?php if (is_admin_logged_in()): ?>
          <li class="nav-item"><a class="nav-link <?= active_nav($active, 'dashboard') ?>" href="/dashboard.php">Dashboard</a></li>
          <li class="nav-item"><a class="nav-link <?= active_nav($active, 'detail') ?>" href="/dashboard.php#requests">Requests</a></li>
          <li class="nav-item ms-lg-2"><a class="btn btn-dark btn-sm px-3" href="/logout.php">Log out</a></li>
        <?php else: ?>
          <li class="nav-item"><a class="nav-link <?= active_nav($active, 'login') ?>" href="/login.php">Admin login</a></li>
          <li class="nav-item ms-lg-2"><a class="btn btn-dark btn-sm px-3" href="/#request-form">New request</a></li>
        <?php endif; ?>
      </ul>
    </div>
  </div>
</nav>
    <?php
}

function render_flash_toast(): void
{
    $flash = get_flash();
    if (!$flash) {
        return;
    }

    $type = $flash['type'] ?? 'info';
    $map = [
        'success' => 'text-bg-success',
        'danger' => 'text-bg-danger',
        'warning' => 'text-bg-warning',
        'info' => 'text-bg-primary',
    ];
    $class = $map[$type] ?? 'text-bg-primary';
    ?>
<div class="toast-container position-fixed top-0 end-0 p-3">
  <div class="toast show align-items-center border-0 <?= e($class) ?>" role="status" aria-live="polite" aria-atomic="true" data-autohide="true">
    <div class="d-flex">
      <div class="toast-body"><?= e((string) ($flash['message'] ?? 'Done.')) ?></div>
      <button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast" aria-label="Close"></button>
    </div>
  </div>
</div>
    <?php
}

function render_footer(string $active = ''): void
{
    $assetVersion = (string) (filemtime(__DIR__ . '/assets/js/main.js') ?: time());
    ?>
<footer class="border-top bg-white py-4 mt-5">
  <div class="container d-flex flex-column flex-lg-row justify-content-between gap-2 small text-secondary">
    <div><?= e(project_name()) ?> · fast intake workflow</div>
    <div class="d-flex gap-3">
      <a href="/" class="link-secondary text-decoration-none">Home</a>
      <?php if (is_admin_logged_in()): ?>
        <a href="/dashboard.php" class="link-secondary text-decoration-none">Dashboard</a>
      <?php else: ?>
        <a href="/login.php" class="link-secondary text-decoration-none">Admin login</a>
      <?php endif; ?>
    </div>
  </div>
</footer>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-YvpcrYf0tY3lHB60NNkmXc5s9fDVZLESaAA55NDzOxhy9GkcIdslK1eN7N6jIeHz" crossorigin="anonymous"></script>
<script src="/assets/js/main.js?v=<?= e($assetVersion) ?>" defer></script>
</body>
</html>
    <?php
}