From 7a84babf1e6be3ad99e31d42a677d40d53b1cae5 Mon Sep 17 00:00:00 2001
From: Danila Fedorin <danila.fedorin@gmail.com>
Date: Sat, 24 Feb 2018 20:08:17 -0800
Subject: [PATCH] Add basic function call parsing.

---
 include/tree.h  |  3 ++-
 src/libabacus.c |  4 ++++
 src/parser.c    | 47 +++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 53 insertions(+), 1 deletion(-)

diff --git a/include/tree.h b/include/tree.h
index 3ffc3bf..5d83631 100644
--- a/include/tree.h
+++ b/include/tree.h
@@ -16,7 +16,8 @@ enum libab_tree_variant_e {
     UNARY_OP,
     BLOCK,
     VOID,
-    IF
+    IF,
+    CALL
 };
 
 /**
diff --git a/src/libabacus.c b/src/libabacus.c
index 3c64e91..5780095 100644
--- a/src/libabacus.c
+++ b/src/libabacus.c
@@ -69,6 +69,10 @@ libab_result libab_register_function(libab* ab, const char* name, libab_function
         result = LIBAB_MALLOC;
     }
 
+    if(result == LIBAB_SUCCESS) {
+        result = libab_convert_lex_result(eval_config_add(&ab->lexer.config, name, TOKEN_FUN));
+    }
+
     if(result == LIBAB_SUCCESS) {
         result = libab_table_put(&ab->table, name, new_entry);
     }
diff --git a/src/parser.c b/src/parser.c
index 3440830..b8d4d39 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -219,6 +219,51 @@ libab_result _parse_if(struct parser_state* state, libab_tree** store_into) {
     return result;
 }
 
+libab_result _parse_call(struct parser_state* state, libab_tree** store_into) {
+    libab_result result =  LIBAB_SUCCESS;
+    libab_tree* temp;
+
+    if(_parser_is_type(state, TOKEN_FUN)) {
+        result = _parser_construct_node_both(state, state->current_match, store_into);
+        if(result == LIBAB_SUCCESS) {
+            (*store_into)->variant = CALL;
+        }
+        _parser_state_step(state);
+    } else {
+        result = LIBAB_UNEXPECTED;
+    }
+
+    if(result == LIBAB_SUCCESS) {
+        result = _parser_consume_char(state, '(');
+    }
+
+    while(result == LIBAB_SUCCESS && !_parser_eof(state) && !_parser_is_char(state, ')')) {
+        result = _parse_expression(state, &temp);
+        if(result == LIBAB_SUCCESS) {
+            result = libab_convert_ds_result(vec_add(&(*store_into)->children, temp));
+            if(result != LIBAB_SUCCESS) {
+                libab_tree_free_recursive(temp);
+            }
+        }
+
+        if(result == LIBAB_SUCCESS && !(_parser_is_char(state, ')') || _parser_is_char(state, ','))) {
+            result = LIBAB_UNEXPECTED;
+        } else if(_parser_is_char(state, ',')) {
+            _parser_state_step(state);
+        }
+    }
+    if(result == LIBAB_SUCCESS) {
+        result = _parser_consume_char(state, ')');
+    }
+
+    if(result != LIBAB_SUCCESS) {
+        libab_tree_free_recursive(*store_into);
+        *store_into = NULL;
+    }
+
+    return result;
+}
+
 libab_result _parse_atom(struct parser_state* state, libab_tree** store_into) {
     libab_result result;
     if(_parser_is_type(state, TOKEN_NUM) || _parser_is_type(state, TOKEN_ID)) {
@@ -231,6 +276,8 @@ libab_result _parse_atom(struct parser_state* state, libab_tree** store_into) {
         result = _parse_if(state, store_into);
     } else if(_parser_is_char(state, '{')) {
         result = _parse_block(state, store_into, 1);
+    } else if(_parser_is_type(state, TOKEN_FUN)) {
+        result = _parse_call(state, store_into);
     } else {
         result = LIBAB_UNEXPECTED;
     }