#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <malloc.h>
#include <sys/stat.h>
#include "mman.h"

int comparator(const void* a, const void* b)
{
    const char* s1, * s2;
    s1 = *(char**)a;
    s2 = *(char**)b;
    int i = 0;
    while (s1[i] == s2[i] && s1[i] != '\n' && s2[i] != '\n')
        i++;
    return (s1[i] - s2[i]);
}

int main()
{
    int file_in = open("input.txt", O_RDWR, 0);
    FILE* file_out = fopen("output.txt", "w");
    if (file_in == -1 || file_out == NULL)
    {
        printf("Opening error\n");
        return 1;
    }
    struct stat data;
	fstat(file_in, &data);
	int size_file = data.st_size;
    char* text = mmap(0, size_file, PROT_READ, MAP_PRIVATE, file_in, 0);
    if (text == MAP_FAILED)
    {
        printf("Opening error\n");
        return 1;
    }
    int txtLen = strlen(text);
    int count_of_string = 0;
    for (int i = 0; i < txtLen; i++)
        if (text[i] == '\n')
            count_of_string++;
    count_of_string++;
    char **strings = (char**) malloc(count_of_string * sizeof(char*));
    if (strings == NULL)
    {
        printf("Memory allocation error\n");
        return 1;
    }
    int posStr = 0, posCur = 0;
    int i = 0;
    printf("Here1\n");
    while (text[i])
    {
        if (text[i] != '\n')
        {
            int j = i + 1;
            while (text[j] != '\n' && text[j] != '\0')
                j++;
            if (text[j] == '\0')
                j++;
            strings[posStr] = (char*)malloc((j - i - 1) * sizeof(char));
            printf("%d\n", posStr);
            for (int k = 0; k < j - i - 1; k++)
                strings[posStr][k] = text[i + k];
            strings[posStr][j - i - 1] = '\n';
            posStr++;
            i = j;
        }
        i++;
    }
    printf("Here2\n");
    qsort(strings, count_of_string, sizeof(char*), comparator);
    printf("Here3\n");
    for (i = 0; i < count_of_string ; i++)
    {
        size_t pos = 0;
        while (strings[i][pos] != '\n') {
            fputc(strings[i][pos], file_out);
            pos++;
        }
        fputc('\n', file_out);
    }
    printf("Here4\n");
    munmap(text, txtLen);
    for (i = 0; i < count_of_string; i++)
		free(strings[i]);
	free(strings);
    close(file_in);
    close(file_out);
    return 0;
}