From 6bab3da52647b34e8d7aaab5d3a680dd1375bebc Mon Sep 17 00:00:00 2001
From: daniel-j <daniel.j.hede@gmail.com>
Date: Sun, 21 Jul 2024 17:18:31 +0200
Subject: [PATCH] Integrate pdfCropMargins for cropping PDFs (#29)

---
 Dockerfile         |  6 ++++++
 index.js           | 52 +++++++++++++++++++++++++++++++++++++++++++++-
 static/upload.html |  3 ++-
 3 files changed, 59 insertions(+), 2 deletions(-)

diff --git a/Dockerfile b/Dockerfile
index 5c67c33..c16ac37 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -16,6 +16,12 @@ RUN wget https://web.archive.org/web/20150803131026if_/https://kindlegen.s3.amaz
     chmod +x /usr/local/bin/kindlegen && \
     rm -rf kindlegen
 
+RUN apk add --no-cache pipx
+
+ENV PATH="$PATH:/root/.local/bin"
+
+RUN pipx install pdfCropMargins
+
 # Copy files needed by npm install
 COPY package*.json ./
 
diff --git a/index.js b/index.js
index 7901275..ebca70b 100644
--- a/index.js
+++ b/index.js
@@ -10,7 +10,8 @@ const serve = require('koa-static')
 const { mkdirp } = require('mkdirp')
 const fs = require('fs')
 const { spawn } = require('child_process')
-const { extname, basename, dirname } = require('path')
+const { join, extname, basename, dirname } = require('path')
+const resolvepath = require('path').resolve
 const FileType = require('file-type')
 const { transliterate } = require('transliteration')
 const sanitize = require('sanitize-filename')
@@ -418,6 +419,55 @@ router.post('/upload', async (ctx, next) => {
         })
         return
       }
+
+    } else if (mimetype == 'application/pdf' && ctx.request.body.pdfcropmargins) {
+      const dir = dirname(ctx.request.file.path)
+      const base = basename(ctx.request.file.path, '.pdf')
+      const outfile = resolvepath(join(dir, `${base}_cropped.pdf`))
+      let p = new Promise((resolve, reject) => {
+        let stderr = ''
+        const pdfcropmargins = spawn('pdfcropmargins', ['-s', '-u', '-o', outfile, basename(ctx.request.file.path)], {
+          // stdio: 'inherit',
+          cwd: dirname(ctx.request.file.path)
+        })
+        pdfcropmargins.once('error', function (err) {
+          fs.unlink(ctx.request.file.path, (err) => {
+            if (err) console.error(err)
+            else console.log('Removed file', ctx.request.file.path)
+          })
+          reject('pdfcropmargins error: ' + err)
+        })
+        pdfcropmargins.once('close', (code) => {
+          fs.unlink(ctx.request.file.path, (err) => {
+            if (err) console.error(err)
+            else console.log('Removed file', ctx.request.file.path)
+          })
+          if (code !== 0) {
+            reject('pdfcropmargins error code: ' + code + '\n' + stderr)
+            return
+          }
+
+          resolve(outfile)
+        })
+        pdfcropmargins.stdout.on('data', function (str) {
+          stderr += str
+          console.log('pdfcropmargins: ' + str)
+        })
+        pdfcropmargins.stderr.on('data', function (str) {
+          stderr += str
+          console.log('pdfcropmargins: ' + str)
+        })
+      })
+      try {
+        data = await p
+      } catch (err) {
+        flash(ctx, {
+          success: false,
+          message: err.replaceAll(basename(ctx.request.file.path), "infile.pdf").replaceAll(outfile, "outfile.pdf")
+        })
+        return
+      }
+
     } else {
       // No conversion
       data = ctx.request.file.path
diff --git a/static/upload.html b/static/upload.html
index e1f6589..07f5f5d 100644
--- a/static/upload.html
+++ b/static/upload.html
@@ -18,6 +18,7 @@
 			<tr><td class="right"><label for="urlinput"><strong>Send url</strong></label></td><td><input type="url" name="url" id="urlinput" autocomplete="off" style="width: 100%"></td></tr>
 			<tr><td class="right"><input type="checkbox" name="kepubify" id="kepubify" checked /></td><td><label for="kepubify"><strong>Kepubify</strong> <em>Kobo only</em></label></td></tr>
 			<tr><td class="right"><input type="checkbox" name="kindlegen" id="kindlegen" checked /></td><td><label for="kindlegen"><strong>KindleGen</strong> <em>Kindle only</em></label></td></tr>
+			<tr><td class="right"><input type="checkbox" name="pdfcropmargins" id="pdfcropmargins" /></td><td><label for="pdfcropmargins"><strong>Crop margins of pdfs</strong></label></td></tr>
 			<tr><td class="right"><input type="checkbox" name="transliteration" id="transliteration" /></td><td><label for="transliteration"><strong>Transliteration of filename</strong></label></td></tr>
 			<tr class="center"><td colspan="2"><input type="submit" value="Upload and send" /></td></tr>
 		</table>
@@ -31,7 +32,7 @@
 	</div>
 	<hr/>
 	<div class="center">
-		Created by djazz. Powered by <a href="https://koajs.com/" target="_blank">Koa</a>, <a href="https://pgaskin.net/kepubify/" target="_blank">Kepubify</a> and <a href="https://www.amazon.com/gp/feature.html?ie=UTF8&docId=1000765211" target="_blank">KindleGen</a><br/>
+		Created by djazz. Powered by <a href="https://koajs.com/" target="_blank">Koa</a>, <a href="https://pgaskin.net/kepubify/" target="_blank">Kepubify</a>, <a href="https://www.amazon.com/gp/feature.html?ie=UTF8&docId=1000765211" target="_blank">KindleGen</a> and <a href="https://github.com/abarker/pdfCropMargins" target="_blank">pdfCropMargins</a><br/>
 		Source code on <a href="https://github.com/daniel-j/send2ereader" target="_blank">Github</a> - <a id="siteurl">https://send.djazz.se</span>
 	</div>
 </div>