channel-renderer.php

<?php

namespace HitchinHackspace\SlackViewer;

use Exception;

abstract class BaseRenderer {
    /**
     * @var int
     */
    protected $page;

    /**
     * @var int
     */
    protected $pageSize;

    /**
     * @var int|null
     */
    protected $messageCount;

    /**
     * @param int|null $page 
     * @param int $pageSize 
     */
    function __construct($page = null, $pageSize = 100) {
        $this->setPagination($page, $pageSize);
    }

    /**
     * @param int|null $page 
     * @param int $pageSize 
     */
    function setPagination($page, $pageSize) {
        $this->page = $page ?: 1;
        $this->pageSize = $pageSize;
    }

    /**
     * @return MessageSequence
     */
    abstract function getMessageSequence();

    /**
     * @return string
     */
    abstract function getPath();

    /**
     * @return string
     */
    abstract function getTitle();

    /**
     * @return int
     */
    function getMessageCount() {
        if ($this->messageCount === null)
            $this->messageCount = $this->getMessageSequence()->getCount();

        return $this->messageCount;
    }

    /**
     * @return Collection<SlackMessage> 
     */
    function getMessages() {
        return $this->getMessageSequence()->getContent($this->getFirstIndex(), $this->pageSize);
    }

    /**
     * @return SlackArchive
     */
    function getArchive() { return $this->getMessageSequence()->getArchive(); }

    /**
     * @return int 
     */
    function getFirstIndex() { return ($this->page - 1) * $this->pageSize; }

    /**
     * @return int
     */
    function getLastIndex() { return min($this->getFirstIndex() + $this->pageSize, $this->getMessageCount()); }

    /**
     * @return int
     */
    function getPageCount() { return ceil($this->getMessageCount() / $this->pageSize); }

    /**
     * @return bool 
     */
    function hasPrevPage() { return $this->page > 1; }

    /**
     * @return bool 
     */
    function hasNextPage() { return $this->page < $this->getPageCount(); }

    /**
     * @return int|null 
     */
    function getPrevPage() { return $this->hasPrevPage() ? $this->page - 1 : null; }

    /**
     * @return int|null 
     */
    function getNextPage() { return $this->hasNextPage() ? $this->page + 1 : null; }
       
    /**
     * @param int $page 
     * @return string 
     */
    function getPageLink($page) { return "?path={$this->getPath()}/$page"; }

    /*
    function getPageName($page) {
        if ($page == 1) 
            return 'First';
        if ($page == $this->getPageCount())
            return 'Last';
        if ($page == $this->page - 1)
            return 'Previous';
        if ($page == $this->page + 1)
            return 'Next';

        return $page;
    }
    */

    /**
     * @param int $page 
     * @param mixed $name 
     */
    function renderPageLink($page, $name) {
        $class = ($page == $this->page) ? ' class="current"' : '';

        $timestamp = $this->getMessageSequence()->getApproximateTimestamp(($page - 1) * $this->pageSize);

        ?>
            <li title="<?= date('d/m/Y', $timestamp) ?>"<?= $class ?>><a href="<?= $this->getPageLink($page) ?>"<?= $class ?>><?= $name ?></a></li>
        <?php
    }

    function renderNav() {
        // Which pages should we link to?

        // How often should we add page links? It depends how many pages there are in total.
        $skip = intval($this->getPageCount() / 10);

        // If it's more than five, make sure it's a multiple of five.
        if ($skip > 5)
            $skip -= ($skip % 5);
        
        // Make sure it's not zero.
        if ($skip < 1)
            $skip = 1;

        $pages = array_merge(
            // An overview of the entire range
            range($this->page, -$skip, -$skip),
            range($this->page, $this->getPageCount() + $skip, $skip),
            // ... plus five pages back and forward from our current location.
            range($this->page - 3, $this->page + 3),
            // ... and the first and last page.
            [1, $this->getPageCount()]
        );

        // Remove those that are out of range.
        $pages = array_filter($pages, function ($page) { return $page > 1 && $page < $this->getPageCount(); });

        // ... and duplicates
        $pages = array_values(array_unique($pages));

        // ... then make sure they're in order.
        sort($pages, SORT_NUMERIC);

        ?>
            <nav class="pagenav">
                <ul>
                    <?php 
                        if ($this->getPageCount() > 1)
                            $this->renderPageLink(1, 'First');
                        if ($this->page > 1)
                            $this->renderPageLink($this->page - 1, 'Prev');

                        foreach ($pages as $page)
                            $this->renderPageLink($page, $page);

                        if ($this->page < $this->getPageCount())
                            $this->renderPageLink($this->page + 1, 'Next');
                        if ($this->getPageCount() > 1)
                            $this->renderPageLink($this->getPageCount(), 'Last');
                    ?>
                </ul>
            </nav>
        <?php
    }

    /**
     * @return string|null
     */
    function getFilePreview($file, $atleast = null) {
        static $thumbKeys = [
            '1024' => 'thumb_1024',
            '960' => 'thumb_960',
            '800' => 'thumb_800',
            '720' => 'thumb_720',
            '480' => 'thumb_480',
            '360' => 'thumb_360',
            '160' => 'thumb_160',
            '80' => 'thumb_80',
            '64' => 'thumb_64'
        ];

        $best = null;

        foreach ($thumbKeys as $size => $key) {
            $url = $file[$key] ?? null;
            if (!$url)
                continue;

            if ($atleast === null)
                return $url;

            if ($size < $atleast)
                return $best;

            $best = $url;
        }

        return null;
    }

    const ELEMENT_HANDLERS = [
        'rich_text_section' => 'renderRichTextElement',
        'text' => 'renderTextElement',
        'user' => 'renderUserElement',
        'link' => 'renderLinkElement',
        'emoji' => 'renderEmojiElement',
        'channel' => 'renderChannelElement'
    ];

    const BLOCK_HANDLERS = [
        'rich_text' => 'renderRichTextBlock'
    ];

    const MESSAGE_HANDLERS = [
        'message' => 'renderBlocks'
    ];

    const SUBTYPE_HANDLERS = [
        'channel_join' => 'renderChannelJoin'
    ];

    function handle($type, $handlers, $subtype, ... $args) {
        $handler = $handlers[$subtype] ?? null;

        if (!$handler)
            throw new Exception("Unrecognised $type type: '$subtype'");

        $this->$handler(... $args);
    }

    function renderTextElement($message, $element) {
        ?>
        <?= htmlspecialchars($element['text']) ?>
        <?php
    }

    function renderRichTextElement($message, $element) {
        foreach ($element['elements'] as $child)
            $this->renderElement($message, $child);
    }

    function renderUserElement($message, $element) {
        $user = $this->getArchive()->getUser($element['user_id']);

        if ($user) {
            ?>
                <span class="user"><?= $user->getName() ?></span>
            <?php
        }
        else {
            ?>
                <span class="user unknown">unknown</span>
            <?php
        }
    }

    function renderLinkElement($message, $element) {
        $url = $element['url'];
        $text = $element['text'] ?? $url;

        ?>
            <a class="message-link" href="<?= $url ?>" target="_blank"><?= $text ?></a>
        <?php
    }

    function renderEmojiElement($message, $element) {
        ?>
            <span class="emoji">&#x<?= $element['unicode'] ?>;</span>
        <?php 
    }

    function renderChannelElement($message, $element) {
        $channel = $this->getArchive()->getChannelByID($element['channel_id']);

        if ($channel) {
            ?>
                <a class="channel-link" href="?path=<?= esc_attr($channel->getName()) ?>"><?= htmlspecialchars($channel->getName()) ?></a>
            <?php
        }
        else {
            ?>
                <a class="channel-link unknown">unknown</a>
            <?php
        }
    }

    function renderElement($message, $element) {
        $this->handle('element', self::ELEMENT_HANDLERS, $element['type'], $message, $element);
    }

    function renderRichTextBlock($message, $block) {
        foreach ($block['elements'] as $element)
            $this->renderElement($message, $element);
    }

    function renderBlock($message, $block) {
        $this->handle('block', self::BLOCK_HANDLERS, $block['type'], $message, $block);
    }

    function renderChannelJoin($message) {
        $user = $this->getArchive()->getUser($message['user']);

        ?>
            <span class="user"><?= $user ? $user->getName() : 'unknown' ?></span> has joined the channel.
        <?php
    }

    function renderBlocks($message) {
        $subtype = $message['subtype'] ?? null;

        if ($subtype) {
            $this->handle('message subtype', self::SUBTYPE_HANDLERS, $subtype, $message);
            return;
        }

        foreach ($message['blocks'] as $block)
            $this->renderBlock($message, $block);
    }

    function renderContent($message) {
        ob_start();

        try {
            $this->handle('message', self::MESSAGE_HANDLERS, $message['type'], $message);
            ob_flush();
        }
        catch (Exception $e) {
            error_log($e);
            ob_clean();

            ?>
                <div class="content-decode-error" title="<?= $e->getMessage(); ?>">
                    <?= htmlspecialchars($message['text']) ?>
                </div>
            <?php

            ob_flush();
        }
        finally {
            ob_end_clean();
        }
    }

    function renderMessage($message) {
        $message = $message->getData();
        $files = $message['files'] ?? [];
        ?>
        <div class="message">
            <?php
                $this->renderContent($message);
                if ($files) { ?>
                    <ul class="files">
                        <?php foreach ($files as $file) { 
                            if ($file['mode'] == 'hidden_by_limit') {
                                ?>
                                    <li class="hidden_by_limit">
                                        Due to Slack limits, this attachment can't be shown.
                                    </li>
                                <?php
                            }
                            else {
                                ?>
                                    <li>
                                        <a target="_blank" href="<?= $file['url_private'] ?>">
                                            <?php
                                                $preview = $this->getFilePreview($file, 160);
                                                if ($preview) {
                                                    ?><img class="file-preview" src="<?= $preview ?>"><?php
                                                }
                                                else {
                                                    ?><?= $file['name'] ?><?php
                                                }
                                            ?>
                                        </a>
                                    </li>
                                <?php
                            }
                        }
                        ?>
                    </ul>
                <?php } ?>
            </div>
        <?php
    }

    function renderMeta($message) {
        $user = $message->getData()['user'] ?? null;
        if ($user)
            $user = $this->getArchive()->getUser($user);
        ?>
            <div class="meta">
                <span class="user-display-name"><?= $user ? $user->getDisplayName() : 'Unknown' ?></span>
                @
                <span class="time"><?= date('Y-m-d H:i:s', $message->getTimestamp()) ?></span>
            </div>
        <?php
    }

    function render($message) {
        $user = $message->getData()['user'] ?? null;
        if ($user)
            $user = $this->getArchive()->getUser($user);
        
        $avatarURL = null;
        if ($user)
            $avatarURL = $user->getAvatarURL(48);

        ?>
            <div class="avatar">
                <?php if ($avatarURL) { ?><img class="avatar" src="<?= $avatarURL ?>"><?php } ?>
            </div>
            <div class="data">
                <?php $this->renderMessage($message); ?>
                <?php $this->renderMeta($message); ?>
            </div>
        <?php
    }
}

class ChannelRenderer extends BaseRenderer {
    /**
     * @var SlackChannel
     */
    protected $channel;

    /**
     * @param SlackChannel $channel
     * @param int|null $page 
     * @param int $pageSize 
     */
    function __construct($channel, $page = null, $pageSize = 100) {
        parent::__construct($page, $pageSize);
        $this->channel = $channel;
    }   

    public function getMessageSequence() { return $this->channel; }

    public function getPath() { return $this->channel->getName(); }

    public function getTitle() { return '#' . htmlspecialchars($this->channel->getName()); }
}

class SearchRenderer extends BaseRenderer {
    /**
     * @var SearchResults
     */
    protected $results;

    /**
     * @param SearchResults $results
     * @param int|null $page 
     * @param int $pageSize 
     */
    function __construct($results, $page = null, $pageSize = 100) {
        parent::__construct($page, $pageSize);
        $this->results = $results;
    }

    public function getMessageSequence() {
        return $this->results;
    }

    public function getPath() {
        $term = urlencode($this->results->getSearchTerm());
        return "search/$term";
    }

    public function getTitle() {
        $term = htmlspecialchars($this->results->getSearchTerm());
        return "Search results for <span class=\"search-highlight\">$term</span>";
    }

    public function renderTextElement($message, $element) {
        $term = $this->results->getSearchTerm();
        $content = $element['text'];
        while (true) {
            $i = stripos($content, $term);
            if ($i === false) {
                echo htmlspecialchars($content);
                break;
            }

            ?>

            <?= htmlspecialchars(substr($content, 0, $i)) ?><span class="search-highlight"><?= htmlspecialchars(substr($content, $i, strlen($term))) ?></span>

            <?php

            $content = substr($content, $i + strlen($term));
        }
    }

    function renderMeta($message) {
        $user = $message->getData()['user'] ?? null;
        if ($user)
            $user = $this->getArchive()->getUser($user);

        $channel = null;
        if ($message instanceof SearchResultMessage) {
            $channel = $message->getChannel();
            $path = $channel->getName() . '/message/' . $message->getOffset() . '#' . $message->getTimestamp();
        }

        ?>
            <a href="<?= $path ? '?path=' . esc_attr($path) : '' ?>" class="meta">
                <span class="user-display-name"><?= $user ? $user->getDisplayName() : 'Unknown' ?></span>
                <?php if ($channel) { ?>
                    in <span class="channel-link"><?= htmlspecialchars($channel->getName()) ?></span>
                <?php } ?>
                <span class="time"><?= date('Y-m-d H:i:s', $message->getTimestamp()) ?></span>
                </a>
        <?php
    }
}