Neovim, refactor to use modules, lua, and LSP

Refactors the neovim config to use nix modules, and changes the plugins
to favor the builtin neovim LSP over COC. Changes all code to use lua
code instead of vimscript.

hmModules/apps/neovim/default.nix

@@ -3,84 +3,91 @@
 {
   options.neovim = {
     enable = lib.mkEnableOption "Enables neovim";
+    languages = {
+      nix.enable = lib.mkEnableOption "Enables nix support";
+    };
+    plugins = {
+      comments.enable = lib.mkEnableOption "Enables nvim-comment";
+      fugitive.enable = lib.mkEnableOption "Enables git-fugitive";
+      lualine.enable = lib.mkEnableOption "Enables lualine";
+      luasnip.enable = lib.mkEnableOption "Enables luasnip snippets";
+      nvimcmp.enable = lib.mkEnableOption "Enables nvim completion";
+      telescope = {
+        enable = lib.mkEnableOption "Enables telescope";
+        fzf.enable = lib.mkEnableOption "Enables telescope-fzf";
+      };
+      treesitter.enable = lib.mkEnableOption "Enables treesitter";
+    };
   };
 
+  imports = [
+    ./plugin/lsp.nix
+    ./plugin/nvimcmp.nix
+    ./plugin/telescope.nix
+    ./plugin/treesitter.nix
+  ];
+
   config = lib.mkIf config.neovim.enable {
     home.sessionVariables = {
       EDITOR = "nvim";
       VISUAL = "nvim";
     };
+
     programs.neovim = {
       enable = true;
-      extraConfig = ''
-        ${builtins.readFile ./init.vim}
+      viAlias = true;
+      vimAlias = true;
+      vimdiffAlias = true;
+
+      extraLuaConfig = ''
+        ${builtins.readFile ./options.lua}
       '';
-      plugins = with pkgs.vimPlugins; [
-        { # Personal Wiki
-          plugin = vimwiki;
-          config = ''
-            let g:vimwiki_list = [{'path': '~/dox/wiki', 'links_space_char': '_',
-                         \ 'ext': '.md', 'syntax': 'markdown'}]
-          '';
-        }
-        { # NNN in vim
-          plugin = nnn-vim;
-          config = ''
-            let g:nnn#layout = { 'window': {
-                \ 'width': 0.35,
-                \ 'height': 0.5,
-                \ 'xoffset': 1.0,
-                \ 'highlight': 'Debug' } } " hover window
-            let g:nnn#action = {
-                \ '<c-t>': 'tab split',
-                \ '<c-s>': 'split',
-                \ '<c-v>': 'vsplit' }
-            let g:nnn#command = 'nnn -HoeT v'
-            let g:nnn#replace_netrw = 1
-            '';
-        }
-        { # Fuzzy searches
-          plugin = fzf-vim;
-          config = ''
-            map <C-f> :Files<CR>
-            map <C-a> :Ag<CR>
-          '';
-        }
-        { # Auto completions
-          plugin = coc-nvim;
-          config = ''
-            function! s:check_back_space() abort
-              let col = col('.') - 1
-              return !col || getline('.')[col - 1]  =~# '\s'
-            endfunction
 
-            inoremap <silent><expr> <TAB>
-                  \ pumvisible() ? "\<C-n>" :
-                  \ <SID>check_back_space() ? "\<TAB>" :
-                  \ coc#refresh()
-            inoremap <expr><S-TAB> pumvisible() ? "\<C-p>" : "\<C-h>"
-          '';
-        }
-        vim-commentary # multi-line comments
-        vim-fugitive # Git Plugin
-        vimtex # Latex support
-        tagbar # File tagging
-
-        # === LOOK AND FEEL ===
-        { # Status Bar
-          plugin = vim-airline;
-          config = ''
-            let g:airline#extensions#tagbar#flags = 'fs'
-          '';
-        }
-        { # Rainbow Parenthesis
-          plugin = rainbow;
-          config = ''
-            let g:rainbow_actve = 1
-          '';
-        }
-        vim-polyglot # Syntax Highlighting
+      extraPackages = with pkgs; [
+        (lib.mkIf config.neovim.languages.nix.enable nil)
       ];
+
+      # Additional packages are added through imports
+      plugins = let
+        lopts = lib.lists.optionals;
+        cfgp = config.neovim.plugins;
+        cfgl = config.neovim.languages;
+
+        comments = lopts cfgp.comments.enable (with pkgs.vimPlugins; [
+          {
+            plugin = comment-nvim;
+            type = "lua";
+            config = "require(\"Comment\").setup()";
+          }
+        ]);
+
+        fugitive = lopts cfgp.fugitive.enable (with pkgs.vimPlugins; [
+          vim-fugitive
+        ]);
+
+        luasnip-pkg = lopts cfgp.luasnip.enable (with pkgs.vimPlugins; [
+          luasnip
+          friendly-snippets
+          (lib.mkIf cfgp.nvimcmp.enable cmp_luasnip)
+        ]);
+
+        lualine = lopts cfgp.lualine.enable (with pkgs.vimPlugins; [
+          {
+            plugin = lualine-nvim;
+            type = "lua";
+            config = ''
+              require("lualine").setup({
+                icons_enabled = true,
+              })
+            '';
+          }
+          nvim-web-devicons
+        ]);
+
+        nix-pkg = lopts cfgl.nix.enable (with pkgs.vimPlugins; [
+          vim-nix
+        ]);
+      in comments ++ fugitive ++ luasnip-pkg ++ lualine ++ nix-pkg;
     };
   };
 }