#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "astg.h"

void getBrackets(char *in, int bpos, char *out){ // gets the content of the brackets that open at bpos
	if (in[0] != '(' && in[0] != '[')
		out = NULL;

	char *input = malloc(strlen(in) + 1);
	char *Pinput = input;
	memcpy(input, in, strlen(in) + 1);

	int i = 0;
	while (i != bpos){
		input++;
		i++;
	}
	i = 0;
	int depth = 0;
	while (input[0] != '\0'){
		out[i] = input[0];
		if (input[0] == '(' || input[0] == '[')
			depth++;
		if (input[0] == ')' || input[0] == ']')
			depth--;
		if (depth == 0){
			i++;
			break;
		}

		input++;
		i++;
	}

	out[i] = '\0';
	free(Pinput);
}

int getContents(char *brackets){
	int i = 0;
	char *num = malloc(strlen(brackets));
	while (brackets[0] != '\0'){
		if (brackets[0] != '[' && brackets[0] != ']'){
			num[i] = brackets[0];
			i++;
		}
		brackets++;
	}
	num[i] = '\0';
	int out = atoi(num);
	free(num);
	return out;
}

ast_node *genAst(char *expression){
	ast_node *out = malloc(sizeof(ast_node));
	
	/* take the expression
	 * get the first operation from it
	 * get the first number from after the expression
	 * if that number is another expression{
	 * 	grab everything inside its braket and then call this function on it
	 * }
	 * get the second number from the expression
	 * if that number is another expression{
	 * 	grab everything inside its braket and then call this function on it
	 * }
	 */

	int i = 0, j = 0;
	int currentTokenVal = -1;

	char *currentToken = malloc(strlen(expression)+1);
	while (expression[i] != '\0'){
		if (expression[i] == '(' || expression[i] == '['){
			getBrackets(expression, i, currentToken);
			currentTokenVal++;
			
			int depth = 0;

			if (i != 0){
				while (expression[i] != '\0'){
					if (expression[i] == '(' || expression[i] == '[')
						depth++;
					if (expression[i] == ')' || expression[i] == ']')
						depth--;
					if (depth == 0){
						break;
					}
					i++;
				}
			}
			
			if (currentTokenVal == 0){
				switch (currentToken[1]) {
					case '+':
						out->operation= ADD;
						break;
					case '-':
						out->operation = SUB;
						break;
					case '*':
						out->operation = MUL;
						break;
					case '/':
						out->operation = DIV;
						break;
				}
			}

			if (currentTokenVal == 1){
				if (currentToken[0] == '(')
					out->left = genAst(currentToken);
				else {
					out->realLeft = getContents(currentToken);
					out->left = NULL;
				}
			} else if (currentTokenVal == 2){ 
				if (currentToken[0] == '(')
					out->right= genAst(currentToken);
				else {
					out->realRight = getContents(currentToken);
					out->right = NULL;
				}
			}
		} 
	i++;
	}
	free(currentToken);	

	return out;
}


int main(int argc, char **argv){
	if (argc < 2)
		exit(1);

	ast_node *head = genAst(argv[1]);

	printf("%d\n", exec(head));

	freeAst(head);
}