PDF BBCode Tag to Automatically Display All PDFs

[Chip (OP)]

Implementing Mozilla's PDF Javascript Viewer by BBCode Tags
Written by Chipper (Andrew Egerszegi) with Claude.ai
Compatibility: SMF 2.0.x & SMF 2.1.x
Description and Notes
Displays both locally stored and attached PDF files in posts using [pdf][/pdf] or [pdf=n][/pdf] tags, rendered with abundled, self-hosted copy of Mozilla's PDF.js viewer in an <iframe>.

* Three ways to use the tag:

   
   * [pdf]https://example.com/file.pdf[/pdf]
    - displays a locally stored pdf file in web root   

    * [pdf=nnnn]
    - displays the database attachment by it's real  "nnnn"
 
    * [pdf=autodisplay][/pdf]
    - displays every PDF attached to this post automatically

    * [pdf=noautodisplay][/pdf]
     - stops automatic displaying (default)
   

This package never edits Subs.php, Subs-Editor.php, or any other core file, on either SMF branch. The pdf tag, its editor toolbar button, and the auto-detect lookup are all added entirely through SMF's own integration hooks (integrate_bbc_codes, integrate_bbc_buttons, integrate_pre_parsebbc)

* On SMF 2.0.x, where hook auto-loading isn't available, registration is done via a small install-time script that registers each hook by name and adds the plugin file to the pre-include list, checking for existing entries first so a reinstall never duplicates anything

Uninstalling reverses only these entries and leaves every other mod's hooks untouched.

* On SMF 2.1.x, registration uses the standard declarative <hook>
  package action. The Package Manager handles registration,a clean removal on its own.

Because nothing here is a text patch against a core file, there is no upgrade/downgrade risk against other mods that might also touch Subs.php or Subs-Editor.php, and uninstalling always cleanly restores the forum to its exact pre-install state.

PDF.js runs entirely client-side. The only network request it makes is to fetch the PDF from the URL you gave the tag and nothing is sent to a third party.

The bundled pdfjs/ folder ships with its own .htaccess, setting the correct MIME type for .mjs/.wasm/.map files, so the PDF.js module worker loads correctly out of the box.

To do:



2.0 is stable

2.1 has some bugs

1. missing button in editor
2. auto loses then pdf line !



Will display PDF files:

1. by URL to web root
2. by it's real database id numbet
3. automatically when attttached to this post

To disable auto-display

nano +690 /var/www/html/Themes/default/Display.template.php

comment this out like shown below:


//                              if (!empty($attachment[&#39;is_pdf&#39;]))
//                              {
//                                      echo &#39;
//                                                                      <iframe src="&#39;, $settings[&#39;theme_url&#39;], &#39;/pdfjs/web/$
//                              }


Modifying the PDF Viewer defaults:

To set the scroll mode (`ScrollMode.PAGE = 3` — that's "one page at a time, scroll/navigate between them" (what you want, instead of continuous vertical which is `VERTICAL = 0`).

nano +4435 /var/www/html/Themes/default/pdfjs/web/viewer.mjs

Change `-1` → `3` (shown below)

Code: [Select]

  scrollModeOnLoad: {
    value: 3,
    kind: OptionKind.VIEWER + OptionKind.PREFERENCE
  },

Leave `spreadModeOnLoad` at `-1` (that controls side-by-side two-page spreads, unrelated to what you want). Reload a PDF after saving and it should open one page at a time with prev/next navigation instead of the continuous scroll.

Debugging the mod:

nano /var/www/html/Sources/Display.php

Find:
loadAttachmentContext(), right after where $attachmentData[$i] = array( is built, before the // If something is unapproved we'll note it so we can sort them. line)

Insert:
"@file_put_contents($boarddir . '/pdfbbc_autotrace.log', date('Y-m-d H:i:s') . ' AUTO-EMBED LOOP: ' . var_export($attachment, true) . "\n", FILE_APPEND);"

If $boarddir isn't already in that list, insert in the variable into the line below:

global $modSettings, $context, $boarddir, ...

Testing:

Display by URL to its webroot filename



Display by it's database id
[pdf=4790][/pdf]

Display every attachment automatically
[pdf=autodisplay][/pdf]