From 29679840d6469d2d9bfa2494dab5e6a48a3fcbb5 Mon Sep 17 00:00:00 2001
From: Andreas Schneider <asn@cryptomilk.org>
Date: Fri, 27 Aug 2021 09:30:42 +0200
Subject: [PATCH] Add support for C-doxygen

---
 lua/neogen.lua                  |   1 +
 lua/neogen/configurations/c.lua | 132 ++++++++++++++++++++++++++++++++
 2 files changed, 133 insertions(+)
 create mode 100644 lua/neogen/configurations/c.lua

diff --git a/lua/neogen.lua b/lua/neogen.lua
index bb30a79..6c0c34f 100644
--- a/lua/neogen.lua
+++ b/lua/neogen.lua
@@ -78,6 +78,7 @@ neogen.setup = function(opts)
             lua = require("neogen.configurations.lua"),
             python = require("neogen.configurations.python"),
             javascript = require("neogen.configurations.javascript"),
+            c = require("neogen.configurations.c"),
         },
     })
 
diff --git a/lua/neogen/configurations/c.lua b/lua/neogen/configurations/c.lua
new file mode 100644
index 0000000..35c6669
--- /dev/null
+++ b/lua/neogen/configurations/c.lua
@@ -0,0 +1,132 @@
+-- hello.c:
+--
+-- #include <stdio.h>
+--
+-- int main(int argc, char *argv[])
+-- {
+--     printf("Hello world!\n");
+--     return 0;
+-- }
+--
+-- AST
+--
+-- preproc_include [0, 0] - [2, 0]
+--   path: system_lib_string [0, 9] - [0, 18]
+-- function_definition [2, 0] - [6, 1]
+--   type: primitive_type [2, 0] - [2, 3]
+--   declarator: function_declarator [2, 4] - [2, 32]
+--     declarator: identifier [2, 4] - [2, 8]
+--     parameters: parameter_list [2, 8] - [2, 32]
+--       parameter_declaration [2, 9] - [2, 17]
+--         type: primitive_type [2, 9] - [2, 12]
+--         declarator: identifier [2, 13] - [2, 17]
+--       parameter_declaration [2, 19] - [2, 31]
+--         type: primitive_type [2, 19] - [2, 23]
+--         declarator: pointer_declarator [2, 24] - [2, 31]
+--           declarator: array_declarator [2, 25] - [2, 31]
+--             declarator: identifier [2, 25] - [2, 29]
+--   body: compound_statement [3, 0] - [6, 1]
+--     expression_statement [4, 4] - [4, 29]
+--       call_expression [4, 4] - [4, 28]
+--         function: identifier [4, 4] - [4, 10]
+--         arguments: argument_list [4, 10] - [4, 28]
+--           string_literal [4, 11] - [4, 27]
+--             escape_sequence [4, 24] - [4, 26]
+--     return_statement [5, 4] - [5, 13]
+--       number_literal [5, 11] - [5, 12]
+
+local c_function_extractor = function(node)
+    local tree = {
+        {
+            retrieve = "first",
+            node_type = "function_declarator",
+            subtree = {
+                {
+                    retrieve = "first",
+                    node_type = "parameter_list",
+                    subtree = {
+                        {
+                            retrieve = "all",
+                            node_type = "parameter_declaration",
+                            subtree = {
+                                {
+                                    retrieve = "all",
+                                    node_type = "identifier",
+                                    extract = true
+                                },
+
+                                {
+                                    retrieve = "all",
+                                    node_type = "pointer_declarator",
+                                    subtree = {
+                                        {
+                                            retrieve = "all",
+                                            node_type = "identifier",
+                                            extract = true
+                                        },
+
+                                        {
+                                            retrieve = "all",
+                                            node_type = "array_declarator",
+                                            subtree = {
+                                                {
+                                                    retrieve = "all",
+                                                    node_type = "identifier",
+                                                    extract = true
+                                                },
+                                            },
+                                        },
+                                    },
+                                },
+                            },
+                        },
+                    },
+                },
+            },
+        },
+        { retrieve = "first", node_type = "return_statement", extract = true },
+    }
+
+    local nodes = neogen.utilities.nodes:matching_nodes_from(node, tree)
+    local res = neogen.utilities.extractors:extract_from_matched(nodes)
+
+    return {
+        parameters = res.identifier,
+        return_statement = res.return_statement,
+    }
+end
+
+return {
+    parent = {
+        func = { "function_declaration", "function_definition" },
+    },
+
+    data = {
+        func = {
+            ["function_declaration|function_definition"] = {
+                ["0"] = {
+                    extract = c_function_extractor,
+                },
+            },
+        },
+    },
+
+    -- Use default granulator and generator
+    granulator = nil,
+    generator = nil,
+
+    template = {
+        annotation_convention = "doxygen",
+        use_default_comment = false,
+
+        doxygen = {
+            { nil, "/* */", { no_results = true } },
+            { nil, "/**" },
+            { nil, " * @brief " },
+            { nil, " *" },
+            { "parameters", " * @param[in] %s " },
+            { "return_statement", " * @returns " },
+            { nil, " */" },
+        },
+    },
+}