<?php
require 'inc/mysqli.inc.php';
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
  if (!isset($_POST['topic_id'], $_POST['description'], $_POST['name'])) {
    header('Location: index.php');
    exit;
  }

  $DATA = $_POST;

  $TOPIC_ID = (int)$DATA['topic_id'];

  foreach ($DATA as $key => $value) {
    $DATA[$key] = trim($value);
  }

  $result = $mysqli->query(
    "
    SELECT `id`
    FROM `re_topic`
    WHERE `id` = {$TOPIC_ID}
    LIMIT 1
    "
  );

  if (!$result->fetch_row()) {
    header('Location: index.php');
    exit;
  }

  if ($DATA['description'] === '') {
    $FORM_ERRORS['description'] = "กรุณาระบุ 'ข้อความ'";
  } elseif (mb_strlen($DATA['description'], 'UTF-8') > 65535) {
    $FORM_ERRORS['description'] = "'ข้อความ' ต้องมีความยาวไม่เกิน 65535 ตัวอักษร";
  }
  if ($DATA['name'] === '') {
    $FORM_ERRORS['name'] = "กรุณาระบุ 'ชื่อ'";
  } elseif (mb_strlen($DATA['name'], 'UTF-8') > 64) {
    $FORM_ERRORS['name'] = "'ชื่อ' ต้องมีความยาวไม่เกิน 64 ตัวอักษร";
  }

  if (!isset($FORM_ERRORS)) {
    $mysqli->query(
      "
      INSERT INTO `re_comment`
      (
        `topic_id`,
        `description`,
        `name`,
        `ip`
      )
      VALUES
      (
        {$TOPIC_ID},
        '{$mysqli->escape_string($DATA['description'])}',
        '{$mysqli->escape_string($DATA['name'])}',
        '{$_SERVER['REMOTE_ADDR']}'
      )
      "
    );
    $comment_id = $mysqli->insert_id;
    $mysqli->query(
      "
      UPDATE `re_topic`
      SET
        `last_commented` = NOW(),
        `num_comments` = `num_comments` + 1,
        `last_commented_name` = '{$mysqli->escape_string($DATA['name'])}'
      WHERE `id` = {$TOPIC_ID}
      "
    );
    header("Location: view.php?topic_id={$TOPIC_ID}#comment-{$comment_id}");
    exit;
  }
} else {
  $TOPIC_ID = empty($_GET['topic_id'])
    ? 0
    : (int)$_GET['topic_id'];
  $DATA = array(
    'description' => '',
    'name' => '',
  );
}

$result = $mysqli->query(
  "
  SELECT
    `id`,
    `created`,
    `title`,
    `description`,
    `name`,
    `ip`,
    `num_comments`,
    `num_views`
  FROM `re_topic`
  WHERE `id` = {$TOPIC_ID}
  LIMIT 1
  "
);
$topic = $result->fetch_assoc();
if (!isset($topic)) {
  $FATAL_ERROR = $TITLE = "ไม่มีกระทู้หมายเลข {$TOPIC_ID} อยู่ในฐานข้อมูล";
  require 'inc/main.inc.php';
}
$ITEMS = array($topic);
$result->free();

$mysqli->query(
  "
  UPDATE `re_topic`
  SET `num_views` = `num_views` + 1
  WHERE `id` = {$TOPIC_ID}
  LIMIT 1
  "
);
if ($topic['num_comments']) {
  $PAGE = empty($_GET['page'])
    ? 1
    : (int)$_GET['page'];
  $ITEMS_PER_PAGE = 100;
  $START_OFFSET = ($PAGE - 1) * $ITEMS_PER_PAGE;
  $result = $mysqli->query("
    SELECT
      `id`,
      `created`,
      `description`,
      `name`,
      `ip`
    FROM `re_comment`
    WHERE `topic_id` = {$TOPIC_ID}
    ORDER BY `created`
    LIMIT {$START_OFFSET}, {$ITEMS_PER_PAGE}
    ");
  while ($comment = $result->fetch_assoc()) {
    $ITEMS[] = $comment;
  }
  $result->free();
  $result = $mysqli->query(
    "
    SELECT COUNT(*)
    FROM `re_comment`
    WHERE `topic_id` = {$TOPIC_ID}
    "
  );
  $FOUND_ROWS = current($result->fetch_row());
  $result->free();
  $NUM_PAGES = ceil($FOUND_ROWS / $ITEMS_PER_PAGE);
} else {
  $NUM_PAGES = 0;
}
$TITLE = $topic['title'];
$PAGE_TEMPLATE = 'inc/view.inc.php';
require 'inc/main.inc.php';