From 6b0bb6a806859337b338d9a63a9659e375870362 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Kier=C3=A1n=20Meinhardt?= <kmein@posteo.de>
Date: Tue, 27 Sep 2022 22:07:03 +0200
Subject: [PATCH] feat(cloud): add script for browsing mega

---
 .bin/toposort.nix | 50 +++++++++++++++++++++++++++++++++++++++++++++++
 configs/cloud.nix | 32 ++++++++++++++++++++++++++----
 2 files changed, 78 insertions(+), 4 deletions(-)
 create mode 100644 .bin/toposort.nix

diff --git a/.bin/toposort.nix b/.bin/toposort.nix
new file mode 100644
index 0000000..c8bbf43
--- /dev/null
+++ b/.bin/toposort.nix
@@ -0,0 +1,50 @@
+let
+  lib = import <nixpkgs/lib>;
+in rec {
+  inherit lib;
+
+  input = [
+    {
+      x = ["pool" "zfs"];
+      y = ["mdadm" "raid1"];
+    }
+    {
+      x = ["pool" "zfs"];
+      y = ["disk" "sda"];
+    }
+    {
+      x = ["mdadm" "raid1"];
+      y = ["disk" "sdb"];
+    }
+    {
+      x = ["mdadm" "raid1"];
+      y = ["disk" "sdc"];
+    }
+  ];
+
+  outNodes = node: graph:
+    lib.unique
+    (builtins.map (e: e.y)
+      (builtins.filter (v: v.x == node) graph));
+
+  vertices = graph:
+    lib.unique
+    (builtins.map (x: x.y) graph ++ builtins.map (x: x.x) graph);
+
+  deleteVertex = node: graph: (builtins.filter (v: v.x != node && v.y != node) graph);
+
+  findSink = graph:
+    lib.findFirst
+    (v: outNodes v graph == [])
+    (lib.trace graph (builtins.abort "No sink found"))
+    (vertices graph);
+
+  topSort = graph:
+    if graph == []
+    then []
+    else if builtins.length graph == 1
+    then let only = builtins.head graph; in [only.y only.x]
+    else let sink = findSink graph; in [sink] ++ topSort (deleteVertex sink graph);
+
+  output = topSort input;
+}
diff --git a/configs/cloud.nix b/configs/cloud.nix
index dfd7dfc..7037298 100644
--- a/configs/cloud.nix
+++ b/configs/cloud.nix
@@ -57,11 +57,11 @@ in {
         user = "kieran";
         password = lib.fileContents <secrets/nextcloud/password>;
         endpoint = "https://cloud.xn--kiern-0qa.de";
+        target = "${config.users.users.me.home}/notes";
       };
     in ''
-      KIERAN_TARGET=${config.users.users.me.home}/notes
-      mkdir -p "$KIERAN_TARGET"
-      ${pkgs.nextcloud-client}/bin/nextcloudcmd --user ${kieran.user} --password ${lib.escapeShellArg kieran.password} --path /Notes "$KIERAN_TARGET" ${kieran.endpoint}
+      mkdir -p ${lib.escapeShellArg kieran.target}
+      ${pkgs.nextcloud-client}/bin/nextcloudcmd --user ${kieran.user} --password ${lib.escapeShellArg kieran.password} --path /Notes ${lib.escapeShellArg kieran.target} ${kieran.endpoint}
     '';
     serviceConfig = {
       Type = "oneshot";
@@ -76,8 +76,32 @@ in {
         ${pkgs.findutils}/bin/find ${config.users.users.me.home}/cloud/syncthing/library -type f
         ${pkgs.findutils}/bin/find ${config.users.users.me.home}/cloud/Seafile/Books -type f
       } | ${pkgs.fzf}/bin/fzf)"
-      ${pkgs.zathura}/bin/zathura "$book"
+      exec ${pkgs.zathura}/bin/zathura "$book"
     '')
+    (let
+      kieran = {
+        user = "kieran.meinhardt@gmail.com";
+        password = lib.fileContents <secrets/mega/password>;
+      };
+      megatools = command: "${pkgs.megatools}/bin/megatools ${command} --username ${lib.escapeShellArg kieran.user} --password ${lib.escapeShellArg kieran.password}";
+    in
+      pkgs.writers.writeDashBin "book-mega" ''
+        set -efu
+        selection="$(${megatools "ls"} | ${pkgs.fzf}/bin/fzf)"
+        test -n "$selection" || exit 1
+
+        tmpdir="$(mktemp -d)"
+        trap clean EXIT
+        clean() {
+          rm -rf "$tmpdir"
+        }
+
+        (
+          cd "$tmpdir"
+          ${megatools "get"} "$selection"
+          exec ${pkgs.zathura}/bin/zathura "$(basename "$selection")"
+        )
+      '')
   ];
 
   fileSystems."/media/moodle" = {