#include "decode.h"
#include <stdio.h>
#include <stdbool.h>

int decode_main(int argc, char* argv[])
{
    bool decoding = true;
    FILE *input_file = fopen(argv[2], "rb");
    if (input_file == NULL) {
        fprintf(stderr, "Error opening input file: %s\n", argv[2]);
        return 1;
    }
    FILE *output_file = fopen(argv[3], "wb");
    if (output_file == NULL) {
        fprintf(stderr, "Error opening output file: %s\n", argv[3]);
        fclose(input_file);
        return 1;
    }
    while (decoding)
    {
        // Read data 
        unsigned char data[1024];
        unsigned char buffer_High[sizeof(data)/2];
        unsigned char buffer_Low[sizeof(data)/2];
        size_t bytes_read = fread(&data, 1, sizeof(data), input_file);
        for (size_t i = 0; i < bytes_read; i++) {
            buffer_High[i] = data[i + (sizeof(data)/2)];
            buffer_Low[i] = data[i];
        }


        if (bytes_read == 0) {
            if (feof(input_file)) {
                decoding = false; // eof reached
            } else {
                fprintf(stderr, "Error reading from input file\n");
                fclose(input_file);
                fclose(output_file);
                return 1;
            }
        }

        // Decode data
        unsigned char decoded_data[sizeof(data)];
        decoded_data[sizeof(data)] = decode_combine_nibbles(*buffer_High, *buffer_Low);
        
        // Write data
        fwrite(decoded_data, 1, bytes_read, output_file);
    }
    return 0;
}