Add nix flake for desktop client

Signed-off-by: Claudio Cambra <claudio.cambra@gmail.com>

admin/nix/flake.nix

@@ -0,0 +1,115 @@
+/*
+ * Copyright (C) by Claudio Cambra <claudio.cambra@nextcloud.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+ * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
+ */
+
+{
+  description = "A flake for the Nextcloud desktop client";
+
+  inputs = {
+    nixpkgs.url = "github:NixOS/nixpkgs/nixpkgs-unstable";
+    flake-utils.url = "github:numtide/flake-utils";
+  };
+
+  outputs = { self, nixpkgs, flake-utils }:
+    with flake-utils.lib;
+    eachSystem [ "aarch64-linux" "x86_64-linux" ] (system:
+        let
+          pkgs = import nixpkgs {
+            inherit system;
+          };
+
+          inherit (pkgs.lib.lists) optional optionals;
+          inherit (pkgs.lib.strings) hasPrefix hasSuffix;
+          isMacOS = hasSuffix "darwin" system;
+          isARM = hasPrefix "aarch64" system;
+
+          nativeBuildInputs = with pkgs; [
+            cmake
+            extra-cmake-modules
+            pkg-config
+            qt5.wrapQtAppsHook
+          ];
+
+          buildInputs = with pkgs; [
+            sqlite
+            openssl
+            pcre
+            inkscape
+
+            qt5.qtbase
+            qt5.qtquickcontrols2
+            qt5.qtsvg
+            qt5.qtgraphicaleffects
+            qt5.qtdeclarative
+            qt5.qttools
+            qt5.qtwebsockets
+
+            libsForQt5.karchive
+            libsForQt5.qtkeychain
+          ] ++ optionals (!isARM) [
+            # Qt WebEngine not available on ARM
+            qt5.qtwebengine
+          ] ++ optionals (stdenv.isLinux) [
+            inotify-tools
+            libcloudproviders
+            libsecret
+
+            libsForQt5.breeze-icons
+            libsForQt5.qqc2-desktop-style
+            libsForQt5.kio
+          ];
+
+          packages.default = with pkgs; stdenv.mkDerivation rec {
+            inherit nativeBuildInputs buildInputs;
+            pname = "nextcloud-client";
+            version = "dev";
+            src = ../../.;
+            dontStrip = true;
+            enableDebugging = true;
+            separateDebugInfo = false;
+            cmakeFlags = if(stdenv.isLinux) then [
+                "-DCMAKE_INSTALL_LIBDIR=lib" # expected to be prefix-relative by build code setting RPATH
+                "-DNO_SHIBBOLETH=1" # allows to compile without qtwebkit
+            ] else [];
+            postPatch = if(stdenv.isLinux) then ''
+              for file in src/libsync/vfs/*/CMakeLists.txt; do
+                substituteInPlace $file \
+                  --replace "PLUGINDIR" "KDE_INSTALL_PLUGINDIR"
+              done
+            '' else "";
+            postFixup = if(stdenv.isLinux) then ''
+              wrapProgram "$out/bin/nextcloud" \
+                --set LD_LIBRARY_PATH ${lib.makeLibraryPath [ libsecret ]} \
+                --set PATH ${lib.makeBinPath [ xdg-utils ]} \
+                --set QML_DISABLE_DISK_CACHE "1"
+            '' else "";
+          };
+
+          apps.default = mkApp {
+            name = "nextcloud";
+            drv = packages.default;
+          };
+
+        in {
+          inherit packages apps;
+          devShell = pkgs.mkShell {
+            inherit buildInputs;
+            nativeBuildInputs = with pkgs; nativeBuildInputs ++[
+              gdb
+              qtcreator
+            ];
+            name = "nextcloud-client-dev-shell";
+          };
+        }
+    );
+}