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

#define MAX_LINE 512

static int add_question(char*** arr, size_t* count, const char* text)
{
	char** tmp = realloc(*arr, (*count + 1) * sizeof(char*));
	if (!tmp)
		return EXIT_FAILURE;
	*arr = tmp;

	(*arr)[*count] = malloc(strlen(text) + 1);
	if (!(*arr)[*count])
		return EXIT_FAILURE;

	strcpy((*arr)[*count], text);
	(*count)++;
	return EXIT_SUCCESS;
}

int load_questions(const char* filename, QuestionSet* qs)
{
	if (!filename || !qs)
		return EXIT_FAILURE;

	FILE* f = fopen(filename, "r");
	if (!f)
		return EXIT_FAILURE;

	qs->general = NULL;
	qs->major = NULL;
	qs->general_count = 0;
	qs->major_count = 0;

	char line[MAX_LINE];
	enum { NONE, GENERAL, MAJOR } mode = NONE;

	while (fgets(line, sizeof(line), f)) {
		line[strcspn(line, "\n")] = '\0';
		if (line[0] == '\0')
			continue;

		if (strcmp(line, "#GENERAL") == 0) {
			mode = GENERAL;
			continue;
		}
		if (strcmp(line, "#MAJOR") == 0) {
			mode = MAJOR;
			continue;
		}

		int res = EXIT_FAILURE;
		switch (mode) {
			case GENERAL:
				res = add_question(
				    &qs->general, &qs->general_count, line);
				break;
			case MAJOR:
				res = add_question(
				    &qs->major, &qs->major_count, line);
				break;
			default:
				continue;
		}

		if (res != EXIT_SUCCESS) {
			fclose(f);
			free_questions(qs);
			return EXIT_FAILURE;
		}
	}

	fclose(f);
	return (qs->general_count && qs->major_count) ? EXIT_SUCCESS
						      : EXIT_FAILURE;
}

void free_questions(QuestionSet* qs)
{
	if (!qs)
		return;

	for (size_t i = 0; i < qs->general_count; i++)
		free(qs->general[i]);
	for (size_t i = 0; i < qs->major_count; i++)
		free(qs->major[i]);

	free(qs->general);
	free(qs->major);

	qs->general = NULL;
	qs->major = NULL;
	qs->general_count = 0;
	qs->major_count = 0;
}