webdice/expression.c

#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <math.h>
#include "expression.h"

union expression* webdice_const(int64_t value){
	union expression* aux = (union expression*) malloc(sizeof(union expression));

	(*aux).constant.id = WEBDICE_CONST;
	(*aux).constant.value = value;

	return aux;
}

union expression* webdice_roll(int64_t count, int64_t roll){
	union expression* aux = (union expression*) malloc(sizeof(union expression));

	(*aux).roll.id = WEBDICE_ROLL;
	(*aux).roll.count = count;
	(*aux).roll.type = roll;

	return aux;
}

union expression* webdice_binary(enum binary_type type, union expression* left, union expression* right){
	union expression* aux = (union expression*) malloc(sizeof(union expression));

	(*aux).binary.id = WEBDICE_BINARY;
	(*aux).binary.operation = type;
	(*aux).binary.left = left;
	(*aux).binary.right = right;

	return aux;
}

union expression* webdice_mul(union expression* left, union expression* right){
	return webdice_binary(WEBDICE_MUL,left,right);
}

union expression* webdice_div(union expression* left, union expression* right){
	return webdice_binary(WEBDICE_DIV,left,right);
}

union expression* webdice_add(union expression* left, union expression* right){
	return webdice_binary(WEBDICE_ADD,left,right);
}

union expression* webdice_sub(union expression* left, union expression* right){
	return webdice_binary(WEBDICE_SUB,left,right);
}

struct expression_result resolve(union expression* root){
	struct expression_result result,left,right;

	int i, j;
	int64_t *values = NULL;
	int64_t total;
	long double size;
	int64_t length = 1;

	switch((*root).id.id){
		case WEBDICE_CONST:
			size = log10l((*root).constant.value);
			length += (int64_t) ceill(size);
			result.min = (*root).constant.value;
			result.max = (*root).constant.value;
			result.expected = (*root).constant.value;
			result.actual = (*root).constant.value;
			result.text = (char*) malloc(length * sizeof(char));
			sprintf(result.text, "%lld",(*root).constant.value);
			break;
		case WEBDICE_ROLL:
			size = ((*root).roll.count + 1) * ceill(30+log10l((*root).roll.count * (*root).roll.type));
			length += (int64_t) size;
			result.min = (*root).roll.count;
			result.max = (*root).roll.count * (*root).roll.type;
			result.expected = (*root).roll.count * ((*root).roll.type + 1.0) / 2.0;
			result.text = (char*) malloc(length * sizeof(char));
			values = (int64_t*) malloc((*root).roll.count * sizeof(int64_t));
			for (i = 0, j = (*root).roll.count, total = 0; i < (*root).roll.count; i++, j--){
				values[i] = 1 + (rand() % (*root).roll.type);
				total += values[i];
				if (i == 0 && j == 1){
					sprintf(result.text,"<span title=\"%lldd%lld=%lld\">%lld</span>", (*root).roll.count, (*root).roll.type, values[i], total);
				}else if (i == 0){
					sprintf(result.text,"<span title=\"%lldd%lld=%lld,", (*root).roll.count, (*root).roll.type, values[i]);
				}else if (j == 1){
					sprintf(&(result.text[strlen(result.text)]),"%lld\">%lld</span>", values[i], total);
				}else{
					sprintf(&(result.text[strlen(result.text)]),"%lld,", values[i]);
				}
			}
			free(values);
			result.actual = total;
			break;
		case WEBDICE_BINARY:
			left = resolve((*root).binary.left);
			right = resolve((*root).binary.right);
			length += 5 + strlen(left.text) + strlen(right.text);
			result.text = (char*) malloc(length * sizeof(char));
			switch((*root).binary.operation){
				case WEBDICE_MUL:
					result.min = left.min * right.min;
					result.max = left.max * right.max;
					result.expected = left.expected * right.expected;
					result.actual = left.actual * right.actual;
					sprintf(result.text,"(%s * %s)",left.text,right.text);
					break;
				case WEBDICE_DIV:
					result.min = left.min / right.max;
					result.max = left.max / right.min;
					result.expected = left.expected / right.expected;
					result.actual = left.actual / right.actual;
					sprintf(result.text,"(%s / %s)",left.text,right.text);
					break;
				case WEBDICE_ADD:
					result.min = left.min + right.min;
					result.max = left.max + right.max;
					result.expected = left.expected + right.expected;
					result.actual = left.actual + right.actual;
					sprintf(result.text,"(%s + %s)",left.text,right.text);
					break;
				case WEBDICE_SUB:
					result.min = left.min - right.max;
					result.max = left.max - right.min;
					result.expected = left.expected - right.expected;
					result.actual = left.actual - right.actual;
					sprintf(result.text,"(%s - %s)",left.text,right.text);
					break;
				default:
					free(result.text);
					result.text = NULL;
					result.min = 0;
					result.max = 0;
					result.expected = 0;
					result.actual = 0;
					break;
			}
			free(left.text);
			free(right.text);
			break;
		default:
			result.text = NULL;
			result.min = 0;
			result.max = 0;
			result.expected = 0;
			result.actual = 0;
			break;
	}
	return result;
}

void free_expression(union expression* root){
	switch((*root).id.id){
		case WEBDICE_BINARY:
			free_expression((*root).binary.left);
			free_expression((*root).binary.right);
		case WEBDICE_CONST:
		case WEBDICE_ROLL:
		default:
			free(root);
			break;
	}
	return;
}