treewide: begin restructuring the module tree

modules/plugins/languages/clang.nix

@@ -0,0 +1,163 @@
+{
+  config,
+  pkgs,
+  lib,
+  ...
+}: let
+  inherit (builtins) attrNames;
+  inherit (lib.lists) isList;
+  inherit (lib.strings) optionalString;
+  inherit (lib.options) mkEnableOption mkOption;
+  inherit (lib.types) bool enum package either listOf str nullOr;
+  inherit (lib.modules) mkIf mkMerge;
+  inherit (lib.nvim.lua) expToLua;
+  inherit (lib.nvim.types) mkGrammarOption;
+  inherit (lib.nvim.dag) entryAnywhere;
+
+  packageToCmd = package: defaultCmd:
+    if isList cfg.lsp.package
+    then expToLua cfg.lsp.package
+    else ''{ "${cfg.lsp.package}/bin/${defaultCmd}" }'';
+
+  cfg = config.vim.languages.clang;
+
+  defaultServer = "ccls";
+  servers = {
+    ccls = {
+      package = pkgs.ccls;
+      lspConfig = ''
+        lspconfig.ccls.setup{
+          capabilities = capabilities;
+          on_attach=default_on_attach;
+          cmd = ${packageToCmd cfg.lsp.package "ccls"};
+          ${optionalString (cfg.lsp.opts != null) "init_options = ${cfg.lsp.opts}"}
+        }
+      '';
+    };
+    clangd = {
+      package = pkgs.clang-tools_16;
+      lspConfig = ''
+        local clangd_cap = capabilities
+        -- use same offsetEncoding as null-ls
+        clangd_cap.offsetEncoding = {"utf-16"}
+        lspconfig.clangd.setup{
+          capabilities = clangd_cap;
+          on_attach=default_on_attach;
+          cmd = ${packageToCmd cfg.lsp.package "clangd"};
+          ${optionalString (cfg.lsp.opts != null) "init_options = ${cfg.lsp.opts}"}
+        }
+      '';
+    };
+  };
+
+  defaultDebugger = "lldb-vscode";
+  debuggers = {
+    lldb-vscode = {
+      package = pkgs.lldb;
+      dapConfig = ''
+        dap.adapters.lldb = {
+          type = 'executable',
+          command = '${cfg.dap.package}/bin/lldb-vscode',
+          name = 'lldb'
+        }
+        dap.configurations.cpp = {
+          {
+            name = 'Launch',
+            type = 'lldb',
+            request = 'launch',
+            program = function()
+              return vim.fn.input('Path to executable: ', vim.fn.getcwd() .. '/', 'file')
+            end,
+            cwd = "''${workspaceFolder}",
+            stopOnEntry = false,
+            args = {},
+          },
+        }
+
+        dap.configurations.c = dap.configurations.cpp
+      '';
+    };
+  };
+in {
+  options.vim.languages.clang = {
+    enable = mkEnableOption "C/C++ language support";
+
+    cHeader = mkOption {
+      description = ''
+        C syntax for headers. Can fix treesitter errors, see:
+        https://www.reddit.com/r/neovim/comments/orfpcd/question_does_the_c_parser_from_nvimtreesitter/
+      '';
+      type = bool;
+      default = false;
+    };
+
+    treesitter = {
+      enable = mkEnableOption "C/C++ treesitter" // {default = config.vim.languages.enableTreesitter;};
+      cPackage = mkGrammarOption pkgs "c";
+      cppPackage = mkGrammarOption pkgs "cpp";
+    };
+
+    lsp = {
+      enable = mkEnableOption "clang LSP support" // {default = config.vim.languages.enableLSP;};
+
+      server = mkOption {
+        description = "The clang LSP server to use";
+        type = enum (attrNames servers);
+        default = defaultServer;
+      };
+
+      package = mkOption {
+        description = "clang LSP server package, or the command to run as a list of strings";
+        example = ''[lib.getExe pkgs.jdt-language-server " - data " " ~/.cache/jdtls/workspace "]'';
+        type = either package (listOf str);
+        default = servers.${cfg.lsp.server}.package;
+      };
+
+      opts = mkOption {
+        description = "Options to pass to clang LSP server";
+        type = nullOr str;
+        default = null;
+      };
+    };
+
+    dap = {
+      enable = mkOption {
+        description = "Enable clang Debug Adapter";
+        type = bool;
+        default = config.vim.languages.enableDAP;
+      };
+      debugger = mkOption {
+        description = "clang debugger to use";
+        type = enum (attrNames debuggers);
+        default = defaultDebugger;
+      };
+      package = mkOption {
+        description = "clang debugger package.";
+        type = package;
+        default = debuggers.${cfg.dap.debugger}.package;
+      };
+    };
+  };
+
+  config = mkIf cfg.enable (mkMerge [
+    (mkIf cfg.cHeader {
+      vim.configRC.c-header = entryAnywhere "let g:c_syntax_for_h = 1";
+    })
+
+    (mkIf cfg.treesitter.enable {
+      vim.treesitter.enable = true;
+      vim.treesitter.grammars = [cfg.treesitter.cPackage cfg.treesitter.cppPackage];
+    })
+
+    (mkIf cfg.lsp.enable {
+      vim.lsp.lspconfig.enable = true;
+
+      vim.lsp.lspconfig.sources.clang-lsp = servers.${cfg.lsp.server}.lspConfig;
+    })
+
+    (mkIf cfg.dap.enable {
+      vim.debugger.nvim-dap.enable = true;
+      vim.debugger.nvim-dap.sources.clang-debugger = debuggers.${cfg.dap.debugger}.dapConfig;
+    })
+  ]);
+}