From 463a4f2d43033dc75d4e84522d0ff670001622bb Mon Sep 17 00:00:00 2001
From: Dmitriy Pleshevskiy <dmitriy@pleshevski.ru>
Date: Mon, 20 May 2024 17:37:37 +0300
Subject: [PATCH] modules/luasnip: add snippets

---
 flake.lock                          |   8 +-
 modules/plugins/snippet/luasnip.nix | 194 +++++++++++++++++++++++++++-
 2 files changed, 197 insertions(+), 5 deletions(-)

diff --git a/flake.lock b/flake.lock
index 81df676..3c5a887 100644
--- a/flake.lock
+++ b/flake.lock
@@ -20,11 +20,11 @@
     },
     "nix2lua": {
       "locked": {
-        "lastModified": 1716204167,
-        "narHash": "sha256-Jo1bjYIMy0Zj4zrkcMrcG0N2Qnhc75OnxL6fnqBG+mg=",
+        "lastModified": 1716215210,
+        "narHash": "sha256-GjwpjhNGdrGH0dElAvcKSFY3nbRw4JYOKtKMmhMsEWw=",
         "ref": "refs/heads/main",
-        "rev": "654eda07372a9a2a03e746d9758f6b39de396a83",
-        "revCount": 51,
+        "rev": "4d3ae67617c2c1301a1a90601e20e15614d20319",
+        "revCount": 52,
         "type": "git",
         "url": "https://git.pleshevski.ru/mynix/nix2lua"
       },
diff --git a/modules/plugins/snippet/luasnip.nix b/modules/plugins/snippet/luasnip.nix
index 6ce6389..1997dcd 100644
--- a/modules/plugins/snippet/luasnip.nix
+++ b/modules/plugins/snippet/luasnip.nix
@@ -1,7 +1,177 @@
 { config, lib, pkgs, ... }:
 
 let
+  inherit (lib.nix2lua) LuaNil scope lset pipe1 call call1;
   cfg = config.plugins.snippet.luasnip;
+
+
+  jump = lib.mkOption {
+    type = with lib.types; nullOr number;
+    default = null;
+    description = ''
+      This determines when this node will be jumped to.
+
+      `:help luasnip-insertnode`
+      `:help luasnip-basics-jump-index`
+    '';
+  };
+  unwrapJump = index: if index == null then LuaNil else index;
+
+  nodes = lib.mkOption {
+    type = with lib.types; listOf (submodule snippetNodeOpts);
+  };
+  unwrapNodes = map (n: n.genConfig);
+
+  genConfig = lib.mkOption {
+    type = lib.types.attrs;
+    internal = true;
+  };
+
+  snippetNodeOpts = { config, ... }: {
+    options = with lib; with types; {
+      text = mkOption {
+        type = nullOr (either str (listOf str));
+        default = null;
+      };
+
+      insert = mkOption {
+        type = nullOr (either number (submodule ({ ... }: {
+          options = {
+            inherit jump;
+            text = mkOption {
+              type = nullOr (either str (listOf str));
+              default = null;
+              description = ''
+                A single string for just one line, a list with entries for multiple lines.
+                This text will be SELECTed when the `insertNode` is jumped into.
+
+                `:help luasnip-insertnode`
+              '';
+            };
+          };
+        })));
+        default = null;
+      };
+
+      choice = mkOption {
+        type = nullOr (submodule ({ ... }: {
+          options = { inherit jump nodes; };
+        }));
+        default = null;
+      };
+
+      snippet = mkOption {
+        type = nullOr (submodule ({ ... }: {
+          options = {
+            inherit jump nodes;
+            indent = mkOption {
+              type = types.str;
+              default = "";
+            };
+          };
+        }));
+        default = null;
+      };
+
+      inherit genConfig;
+    };
+
+    config = {
+      genConfig =
+        let
+          ins = config.insert;
+          ch = config.choice;
+          sn = config.snippet;
+        in
+        if config.text != null then call1 "t" config.text
+        else if ins != null then
+          if builtins.isInt ins then call "i" [ ins ]
+          else call "i" [ (unwrapJump ins.jump) ins.text ]
+        else if ch != null then
+          call "c" [ (unwrapJump ch.jump) (unwrapNodes ch.nodes) ]
+        else if sn != null then
+          if sn.indent != "" then
+            call "isn" [ (unwrapJump sn.jump) (unwrapNodes sn.nodes) sn.indent ]
+          else call "sn" [ (unwrapJump sn.jump) (unwrapNodes sn.nodes) ]
+        else null;
+    };
+  };
+
+  snippetOpts = { name, ... } @ sub: {
+    options = with lib; with types; {
+      context = mkOption {
+        type = either str attrs;
+        description = ''
+          `:help luasnip-snippets';
+        '';
+      };
+
+      nodes = nodes // { default = [ ]; };
+
+      inherit genConfig;
+    };
+
+    config = {
+      context = lib.mkDefault name;
+
+      genConfig = call "s" [ sub.config.context (unwrapNodes sub.config.nodes) ];
+    };
+  };
+
+  snippetGroupOpts = { ... } @ sub: {
+    options = with lib; {
+      filetype = mkOption {
+        type = types.str;
+      };
+
+      opts = {
+        type = mkOption {
+          type = types.nullOr (types.enum [ "snippets" "autosnippets" ]);
+          default = null;
+        };
+        key = mkOption {
+          type = types.nullOr types.str;
+          default = null;
+        };
+        override_priority = mkOption {
+          type = types.nullOr types.number;
+          default = null;
+          description = ''
+            Set priority for all snippets.
+
+            `:help luasnip-api`
+          '';
+        };
+        default_priority = mkOption {
+          type = types.nullOr types.number;
+          default = null;
+          description = ''
+            Set priority only for snippets without snippet priority.
+
+            `:help luasnip-api`
+          '';
+        };
+      };
+
+      snippets = mkOption {
+        type = types.attrsOf (types.submodule snippetOpts);
+        default = { };
+      };
+
+      inherit genConfig;
+    };
+
+    config = {
+      genConfig =
+        let plugin = config.plugin.luasnip; in
+        let inherit (sub.config) filetype snippets opts; in
+        pipe1 plugin.var (call "add_snippets" [
+          filetype
+          (map (s: s.genConfig) (builtins.attrValues snippets))
+          opts
+        ]);
+    };
+  };
 in
 {
   options.plugins.snippet.luasnip = with lib; {
@@ -13,12 +183,34 @@ in
       type = types.attrs;
       default = { };
     };
+
+    snippetGroups = mkOption {
+      type = types.listOf (types.submodule snippetGroupOpts);
+      default = [ ];
+    };
   };
 
   config = lib.mkIf cfg.enable {
-    plugin.luasnip = {
+    plugin.luasnip = rec {
       inherit (cfg) package;
+      varName = "luasnip";
       setupSettings = cfg.settings;
+      afterSetup = lib.mkIf (cfg.snippetGroups != [ ]) [
+        (scope (lib.flatten [
+          (lib.mapAttrsToList (k: v: lset k (pipe1 varName v)) {
+            s = "snippet";
+            sn = "snippet_node";
+            isn = "indent_snippet_node";
+            t = "text_node";
+            i = "insert_node";
+            f = "function_node";
+            c = "choice_node";
+            d = "dynamic_node";
+            r = "restore_node";
+          })
+          (map (sg: sg.genConfig) cfg.snippetGroups)
+        ]))
+      ];
     };
   };
 }