From 4dd606a60b9a94037cca2eb0fa8db7523f0da27e Mon Sep 17 00:00:00 2001
From: Niklas Sirch <sirniklax@gmail.com>
Date: Sun, 12 Jan 2025 23:59:32 +0100
Subject: [PATCH] feat(pageColor): add option to invert pdf pageColor

---
 assets/main.mjs                  | 26 ++++++++++++++++++++++++++
 package.json                     | 23 ++++++++++++++++++++++-
 src/pdf_viewer_provider.d.ts.map |  2 +-
 src/pdf_viewer_provider.ts       |  6 ++++++
 4 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/assets/main.mjs b/assets/main.mjs
index 9c9ac48..7e57655 100644
--- a/assets/main.mjs
+++ b/assets/main.mjs
@@ -30,6 +30,32 @@ PDFViewerApplicationOptions.set("defaultUrl", "");
 PDFViewerApplicationOptions.set("disablePreferences", true);
 PDFViewerApplicationOptions.set("workerSrc", config.workerSrc);
 
+function invertOrResetPageColor(doInvert) {
+  const invertFilter = doInvert
+    ? "invert(64%) contrast(228%) brightness(80%) hue-rotate(180deg)"
+    : null;
+
+  document.getElementById("viewer").style.filter = invertFilter;
+  document.getElementById("thumbnailView").style.filter = invertFilter;
+}
+
+switch (config.pageColorTheme) {
+  case "Follow system":
+    const darkModePreference = window.matchMedia(
+      "(prefers-color-scheme: dark)"
+    );
+    invertOrResetPageColor(darkModePreference.matches);
+    darkModePreference.addEventListener("change", (e) => {
+      invertOrResetPageColor(e.matches);
+    });
+    break;
+  case "Unchanged":
+    break;
+  case "Invert":
+    invertOrResetPageColor(true);
+    break;
+}
+
 void (async () => {
   await window.PDFViewerApplication.initializedPromise;
   window.PDFViewerApplication.open(config);
diff --git a/package.json b/package.json
index d64666f..20b3c91 100644
--- a/package.json
+++ b/package.json
@@ -33,7 +33,28 @@
           }
         ]
       }
-    ]
+    ],
+    "configuration": {
+      "type": "object",
+      "title": "vscode-pdf",
+      "properties": {
+        "vscode-pdf.pageColorTheme": {
+          "type": "string",
+          "default": "Unchanged",
+          "enum": [
+            "Follow system",
+            "Unchanged",
+            "Invert"
+          ],
+          "enumDescriptions": [
+            "Dark system theme: invert; Light system theme: unchanged",
+            "Don't change the page color theme",
+            "Invert the page color theme"
+          ],
+          "description": "Change the page color theme"
+        }
+      }
+    }
   },
   "scripts": {
     "vscode:prepublish": "npm run package",
diff --git a/src/pdf_viewer_provider.d.ts.map b/src/pdf_viewer_provider.d.ts.map
index f38379f..b1f7ac5 100644
--- a/src/pdf_viewer_provider.d.ts.map
+++ b/src/pdf_viewer_provider.d.ts.map
@@ -1 +1 @@
-{"version":3,"file":"pdf_viewer_provider.d.ts","sourceRoot":"","sources":["pdf_viewer_provider.ts"],"names":[],"mappings":"AAiBA,OAAO,EACL,KAAK,4BAA4B,EACjC,UAAU,EACV,KAAK,gBAAgB,EACrB,GAAG,EAEH,KAAK,YAAY,EAElB,MAAM,QAAQ,CAAC;AAKhB,OAAO,EAAE,WAAW,EAAE,MAAM,gBAAgB,CAAC;AAiB7C,qBAAa,iBAAkB,YAAW,4BAA4B;IACpE,gBAAuB,QAAQ,cAAc;WAE/B,QAAQ,CAAC,OAAO,EAAE,gBAAgB;IAUhD,gCAAgC;IAChC,OAAO,CAAC,QAAQ,CAAC,QAAQ,CAA2B;IAEpD,OAAO,CAAC,aAAa,CAAM;gBAEf,OAAO,EAAE,gBAAgB;IAI/B,kBAAkB,CAAC,GAAG,EAAE,GAAG;IAmBjC,OAAO,CAAC,WAAW;IAKb,mBAAmB,CACvB,QAAQ,EAAE,WAAW,EACrB,YAAY,EAAE,YAAY,GACzB,OAAO,CAAC,IAAI,CAAC;IAmBhB,OAAO,CAAC,iBAAiB;CAsC1B"}
\ No newline at end of file
+{"version":3,"file":"pdf_viewer_provider.d.ts","sourceRoot":"","sources":["pdf_viewer_provider.ts"],"names":[],"mappings":"AAiBA,OAAO,EACL,KAAK,4BAA4B,EACjC,UAAU,EACV,KAAK,gBAAgB,EACrB,GAAG,EAEH,KAAK,YAAY,EAGlB,MAAM,QAAQ,CAAC;AAKhB,OAAO,EAAE,WAAW,EAAE,MAAM,gBAAgB,CAAC;AAkB7C,qBAAa,iBAAkB,YAAW,4BAA4B;IACpE,gBAAuB,QAAQ,cAAc;WAE/B,QAAQ,CAAC,OAAO,EAAE,gBAAgB;IAUhD,gCAAgC;IAChC,OAAO,CAAC,QAAQ,CAAC,QAAQ,CAA2B;IAEpD,OAAO,CAAC,aAAa,CAAM;gBAEf,OAAO,EAAE,gBAAgB;IAI/B,kBAAkB,CAAC,GAAG,EAAE,GAAG;IAmBjC,OAAO,CAAC,WAAW;IAKb,mBAAmB,CACvB,QAAQ,EAAE,WAAW,EACrB,YAAY,EAAE,YAAY,GACzB,OAAO,CAAC,IAAI,CAAC;IAmBhB,OAAO,CAAC,iBAAiB;CA2C1B"}
\ No newline at end of file
diff --git a/src/pdf_viewer_provider.ts b/src/pdf_viewer_provider.ts
index 3f1f831..039beec 100644
--- a/src/pdf_viewer_provider.ts
+++ b/src/pdf_viewer_provider.ts
@@ -23,6 +23,7 @@ import {
   type Webview,
   type WebviewPanel,
   window,
+  workspace,
 } from "vscode";
 
 import rawViewerHtml from "../assets/pdf.js/web/viewer.html";
@@ -122,9 +123,14 @@ export class PDFViewerProvider implements CustomReadonlyEditorProvider {
 
     const cspSource = webview.cspSource;
 
+    const pageColorTheme = workspace
+      .getConfiguration("vscode-pdf")
+      .get("pageColorTheme");
+
     const settings = {
       url: `${webview.asWebviewUri(document.uri)}`,
       workerSrc: `${resolvePdfJsURI("build", "pdf.worker.mjs")}`,
+      pageColorTheme,
     };
 
     return viewerHtml