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





#include "tokenizer.h"






uint32_t get_file_size(const char *filename) {
    FILE *file = fopen(filename, "rb");
    if (!file) {
        perror("fopen");
        exit(EXIT_FAILURE);
    }

    if (fseek(file, 0, SEEK_END)!= 0) {
        perror("fseek");
        exit(EXIT_FAILURE);
    }

    uint32_t size = ftell(file);
    if (size == -1) {
        perror("ftell");
        exit(EXIT_FAILURE);
    }

    fclose(file);
    return size;
}


int main(int argc, char *argv[]) {
	if(argc < 3) {
		printf("Needs at least 2 arguments\n");
		return 1;
	}

	char *fname[2] = {argv[1], argv[2]};
	int fd[2] = {
		open(fname[0], O_RDONLY), 
		open(fname[1], O_CREAT | O_WRONLY, 0644)
	};
	
	printf("Vocab size is %d\n", tokenizer.get_vocab_size());
	printf("File names: %s, %s\n", fname[0], fname[1]);
	printf("Got file descriptor: %d, %d\n", fd[0], fd[1]);

	uint32_t size = get_file_size(fname[0]);
	uint8_t *data = (uint8_t *) malloc(size * sizeof(uint8_t));
	uint32_t n = read(fd[0], data, size * sizeof(uint8_t));

	printf("Expected file size of %d bytes\n", size);
	printf("Read %d bytes\n", n);
	if (size != n) perror(0);

	uint8_t *p = data;
	uint32_t d = 0;
	for (int i = 0; *p; ++i) {
		uint16_t tok = tokenizer.encode(&tokenizer, &p);
		write(fd[1], &tok, sizeof(uint16_t));
		
		if (i % 10000 == 0) {
			printf("Current token %d | Index position %d | Remaining %d | Tokenization delta %ld\n", tok, i, d, d - ((data + n) - p));
			d = (data + n) - p;
		}

	}

	printf("\n");
	return 0;
}