<?php
// app/controllers/Emojis.php
header('Content-Type: application/json; charset=utf-8');

require_once __DIR__.'/../helpers/auth.php';
require_once __DIR__.'/../helpers/filters.php';
require_once __DIR__.'/../helpers/usage.php';

// Plan + whitelist
$planInfo = resolve_plan();
$isPro    = $planInfo['pro'];
$isWl     = $planInfo['whitelist'];
$acct     = $planInfo['account'];
$key      = $planInfo['key'];
$planName = $isPro ? 'pro' : ($isWl ? 'whitelist' : 'free');

// Caps
$maxLimit = $isPro ? 50 : 20;
$maxPages = $isPro ? 20 : 5;
if ($isWl) { $maxLimit = 100; $maxPages = 1000; }

// Params
$qParam   = trim((string)($_GET['q'] ?? ''));
$catParam = trim((string)($_GET['category'] ?? ''));
$subParam = trim((string)($_GET['subcategory'] ?? ''));
$page     = max((int)($_GET['page'] ?? 1), 1);
$limit    = min(max((int)($_GET['limit'] ?? $maxLimit), 1), $maxLimit);

// Category map (slugs → labels)
$CATEGORY_MAP = [
  'all'=>'all','smileys'=>'Smileys & Emotion','people'=>'People & Body','animals'=>'Animals & Nature','food'=>'Food & Drink','travel'=>'Travel & Places','activities'=>'Activities','objects'=>'Objects','symbols'=>'Symbols','flags'=>'Flags'
];

$catLabel = '';
if ($catParam !== '' && strtolower($catParam) !== 'all') {
  $catLabel = $CATEGORY_MAP[strtolower($catParam)] ?? $catParam;
}
$subSlug = $subParam !== '' ? dw_slugify($subParam) : '';

$q = $qParam; $cat = $catLabel; $sub = $subSlug;

// Usage (Free counted, Pro/WL unlimited)
$limitDaily = $isWl ? null : ($isPro ? null : (int)cfg('free_daily_limit', 50));

$bucket = bucket_id($key);
$ymd    = day_key();
$usage  = usage_load($bucket, $ymd);
if ($limitDaily !== null) $usage['limit'] = $limitDaily;

$signature = sig_query($q, $cat, $sub);
$sigKey    = $signature.'|p1'; // only page 1 increments
$atCap     = false;

if ($limitDaily !== null && $page === 1 && !isset($usage['seen'][$sigKey])) {
  if ($usage['used'] >= $limitDaily) {
    $atCap = true;
  } else {
    $usage['used'] = (int)$usage['used'] + 1;
    $usage['seen'][$sigKey] = 1;
    usage_save($bucket, $ymd, $usage);
  }
}

if ($page > $maxPages) {
  echo json_encode(['items'=>[],'page'=>$page,'limit'=>$limit,'total'=>0,'plan'=>$planName,'message'=>'Page limit reached for your plan.']);
  exit;
}

// Soft cap
if ($atCap) {
  header('X-Dewemoji-Plan: '.$planName);
  if ($limitDaily === null) {
    header('X-RateLimit-Limit: unlimited'); header('X-RateLimit-Remaining: unlimited');
  } else {
    header('X-RateLimit-Limit: '.$usage['limit']); header('X-RateLimit-Remaining: 0');
  }
  header('X-RateLimit-Reset: '.strtotime('tomorrow 00:00:00 UTC'));
  echo json_encode([
    'items'=>[],'page'=>$page,'limit'=>$limit,'total'=>0,'plan'=>$planName,
    'usage'=>[
      'used'=>(int)$usage['used'],
      'limit'=>$limitDaily,
      'remaining'=> $limitDaily===null ? null : max(0, $limitDaily - (int)$usage['used']),
      'window'=>'daily',
      'window_ends_at'=>gmdate('c', strtotime('tomorrow 00:00:00 UTC')),
      'count_basis'=>'distinct_query'
    ],
    'message'=>'Daily free limit reached. Upgrade to Pro for unlimited usage.'
  ]);
  exit;
}

// Load data
$DATA_PATHS = [
  __DIR__.'/../data/emojis.json',
  __DIR__.'/../../data/emojis.json', // fallback if you keep old path
];
$json = null;
foreach ($DATA_PATHS as $p) { if (is_file($p)) { $json = file_get_contents($p); break; } }
if ($json === null) { http_response_code(500); echo json_encode(['error'=>'data_not_found']); exit; }
$data  = json_decode($json, true) ?: [];
$items = $data['emojis'] ?? [];

// Filter
$items = array_values(array_filter($items, function($e) use ($q,$cat,$sub) {
  if ($cat !== '') {
    if (dw_slugify($e['category'] ?? '') !== dw_slugify($cat)) return false;
  }
  if ($sub !== '') {
    if (dw_slugify($e['subcategory'] ?? '') !== $sub) return false;
  }
  if ($q !== '') {
    $hay = strtolower(implode(' ', [
      $e['emoji'] ?? '', $e['name'] ?? '', $e['slug'] ?? '',
      $e['category'] ?? '', $e['subcategory'] ?? '',
      implode(' ', $e['keywords_en'] ?? []),
      implode(' ', $e['keywords_id'] ?? []),
      implode(' ', $e['aliases'] ?? []),
      implode(' ', $e['shortcodes'] ?? []),
    ]));
    foreach (preg_split('/\s+/', strtolower($q)) as $tok) {
      if ($tok !== '' && strpos($hay, $tok) === false) return false;
    }
  }
  return true;
}));

$total  = count($items);
$offset = ($page - 1) * $limit;
$items  = array_slice($items, $offset, $limit);

// Shape + tone
$items = array_map(function($raw) use ($planName, $isPro) {
  $e = filterEmoji($raw, $planName, true);
  $e['supports_skin_tone'] = dw_supports_skin_tone($raw) || dw_supports_skin_tone($e);
  $e['skin_tone_modifiers'] = dw_skin_tone_modifiers();
  if ($e['supports_skin_tone'] && !empty($e['emoji'])) {
    $base = dw_strip_tone($e['emoji']);
    if ($base !== '') {
      $e['emoji_base'] = $base;
      if ($isPro) { $e['variants'] = dw_build_tone_variants($base); }
    }
  }
  return $e;
}, $items);

// ETag (exclude dynamic usage)
$etag = '"'.sha1(json_encode([$page,$limit,$q,$cat,$sub,$planName,$total,$items])).'"';
header('ETag: '.$etag);
header('Cache-Control: public, max-age=120');
if (($_SERVER['HTTP_IF_NONE_MATCH'] ?? '') === $etag) { http_response_code(304); exit; }

// Rate-limit headers
header('X-Dewemoji-Plan: '.$planName);
if ($limitDaily === null) {
  header('X-RateLimit-Limit: unlimited'); header('X-RateLimit-Remaining: unlimited');
} else {
  header('X-RateLimit-Limit: '.$usage['limit']);
  header('X-RateLimit-Remaining: '.max(0, $usage['limit'] - (int)$usage['used']));
}
header('X-RateLimit-Reset: '.strtotime('tomorrow 00:00:00 UTC'));

// Response
echo json_encode([
  'items'=>$items,
  'page'=>$page,
  'limit'=>$limit,
  'total'=>$total,
  'plan'=>$isPro ? 'pro' : 'free',
  'usage'=>[
    'used'=>(int)$usage['used'],
    'limit'=>$limitDaily,
    'remaining'=> $limitDaily===null ? null : max(0, $limitDaily - (int)$usage['used']),
    'window'=>'daily',
    'window_ends_at'=>gmdate('c', strtotime('tomorrow 00:00:00 UTC')),
    'count_basis'=>'distinct_query'
  ],
], JSON_UNESCAPED_UNICODE);