1 files changed, 116 insertions, 0 deletions
diff --git a/parser.c b/parser.c
new file mode 100644
index 0000000..9bbc50b
--- /dev/null
+++ b/parser.c
@@ -0,0 +1,116 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdbool.h>
+#include <ctype.h>
+#include "stack.h"
+#include "parser.h"
+#include "eval.h"
+
+static unsigned int jumpdist;
+
+static char *readexpr(char *expr){
+	char *out = malloc(strlen(expr+1));
+	char *c = expr;	
+	stack *s = push(NULL, *c);
+	int i;
+
+	for (i = 0; s->len != 0; i++){
+		out[i] = *c;
+		c++;
+		if (*c == '(') s = push(s, '(');
+		else if (*c == ')' && peek(s) == '(') pop(s);
+	}
+	cleanstack(s);
+
+	out[i] = ')';
+	out[i+1] = 0;
+	out = realloc(out, strlen(out));
+	jumpdist = i+1;
+	return out;
+}
+
+static char *readval(char *expr){
+	char *out = strdup(expr);
+	char *gap = strchr(out, ' ');
+	if (gap == NULL) gap = strchr(out, ')');
+	jumpdist = (gap - out)+1;
+	*gap = 0;
+	out = realloc(out, strlen(out));
+	return out;
+}
+
+static luckyval *readargs(char *expr){
+	luckyval *head = malloc(sizeof(luckyval));
+
+	if (*expr != ')' && expr[0] != 0){
+		if (expr[0] == '(' ){ // nested function
+			char *subexpr = readexpr(expr);
+			expr += jumpdist + 1;
+			head->tree = parse(subexpr);
+			head->type = LUCKYTREE;
+			free(subexpr);
+		}
+		else if (strchr(expr, '.') != NULL){ // float
+			char *val = readval(expr);
+			expr += jumpdist;
+			head->f = atof(val);
+			head->type = LUCKYFLOAT;
+			free(val);
+		}
+		else if (isdigit(expr[0])){ // int
+			char *val = readval(expr);
+			expr += jumpdist;
+			head->i = atoi(val);
+			head->type = LUCKYINT;
+			free(val);
+		} 
+		else { // var name
+			char *val = readval(expr);
+			expr += jumpdist;
+			head->var = strdup(val);
+			head->type = LUCKYVAR;
+		}
+	} else return NULL;
+
+	head->nextelement = readargs(expr);
+	return head;
+}
+
+luckytree *parse(char *expr){
+	char *c = expr;	
+	stack *s = push(NULL, *c);
+	while (*c != 0){
+		c++;
+		if (*c == '(') s = push(s, '(');
+		else if (*c == ')' && peek(s) == '(') pop(s);
+	}
+	if (s->len != 0){
+		printf("%s\n", expr);
+		for (int i = 0; i < (c - expr) - 1; i++) printf(" ");
+		printf("^\n");
+		printf("bracket mismatch!\n");
+		exit(1);
+	}
+	cleanstack(s);
+
+	luckytree *tree = malloc(sizeof(luckytree));
+
+	int funcnamelen;
+	if (strchr(expr+1, ' ') == NULL) 
+		funcnamelen = (strchr(expr+1, ')') - expr) - 1;
+	else
+		funcnamelen = (strchr(expr+1, ' ') - expr) - 1;
+
+	tree->function = malloc(funcnamelen + 1);
+
+	memcpy(tree->function, expr + 1, funcnamelen);
+	tree->function[funcnamelen] = 0;
+
+	expr += funcnamelen + 2;
+
+	tree->arguments = readargs(expr);
+
+	return tree;
+}
+