megapixels-next: fix so it can save images as .jpg instead of just .dnf

hosts/common/programs/megapixels-next.nix

@@ -9,7 +9,10 @@
 # - when run against linux mainline: launch hangs at "[libmegapixels] ".
 #   i seem to recall this from 2024-05-11: the patch i disabled during the megapixels-next update to 2024-09-03 was a memory safety issue,
 #   which was causing a crash during the error message printing. so rebasing that would get me an error message, but still no fix.
-{ pkgs, ... }:
+{ config, pkgs, ... }:
+let
+  cfg = config.sane.programs.megapixels-next;
+in
 {
   sane.programs.megapixels-next = {
     packageUnwrapped = pkgs.megapixels-next.overrideAttrs (base: {
@@ -53,11 +56,15 @@
       "/sys/class/leds"  #< for flash, presumably
     ];
     sandbox.whitelistAvDev = true;
-    gsettingsPersist = [
-      # pretty sure one of these is the new directory, one the old, not sure which
-      "me/gapixels/megapixels"  #< needs to set `postprocessor` else it will segfault during post-process
-      "org/postmarketos/megapixels"
-    ];
+    gsettings."me/gapixels/megapixels" = {
+      # **required** for it to find its postprocess script
+      postprocessor = "${cfg.package}/share/megapixels/postprocess.sh";
+      save-raw = false;
+    };
+    gsettings."org/sigxcpu/feedbackd/application/me-gapixels-megapixels" = {
+      # optional, to disable shutter sound
+      profile = "silent";
+    };
 
     env.CAMERA = "me.gapixels.Megapixels.desktop";
   };

hosts/common/programs/megapixels.nix

@@ -42,14 +42,12 @@
     ];
     sandbox.whitelistAvDev = true;
     gsettingsPersist = [
-      # pretty sure one of these is the new directory, one the old, not sure which
-      "me/gapixels/megapixels"  #< needs to set `postprocessor` else it will segfault during post-process
-      "org/postmarketos/megapixels"
+      "org/postmarketos/megapixels"  #< needs to set `postprocessor` else it will segfault during post-process
     ];
     # source code references /proc/device-tree/compatible, but it seems to be alright either way
     # sandbox.keepPidsAndProc = true;
 
-    mime.priority = 200;  #< fallback
+    mime.priority = 200;  #< fallback; prefer `megapixels-next` if it's installed
     env.CAMERA = lib.mkDefault "org.postmarketos.Megapixels.desktop";
   };
 }

pkgs/by-name/megapixels-next/package.nix

@@ -15,7 +15,14 @@
   wrapGAppsHook4,
   xorg,
   zbar,
+# optional runtime dependencies, used for post-processing .dng -> .jpg
+  exiftool,
+  graphicsmagick,
+  libraw,
 }:
+let
+  runtimePath = lib.makeBinPath [ libraw graphicsmagick exiftool ];
+in
 stdenv.mkDerivation {
   pname = "megapixels-next";
   version = "1.6.1-unstable-2024-11-04";
@@ -49,6 +56,12 @@ stdenv.mkDerivation {
     glib-compile-schemas $out/share/glib-2.0/schemas
   '';
 
+  preFixup = ''
+    gappsWrapperArgs+=(
+      --suffix PATH : ${lib.escapeShellArg runtimePath}
+    )
+  '';
+
   strictDeps = true;
 
   passthru.updateScript = unstableGitUpdater { };