#include <stdlib.h>

#include "rec_io.h"

struct rec_io {
    char input[MAX_RECORD_LENGTH];
    char * fields[MAX_RECORD_LENGTH/2 + 1];
    char separator[MAX_SEPARATOR_LENGTH];
    unsigned int separator_length;
    unsigned int fields_count;
};

struct rec_io * rec_io_new() {
    struct rec_io * this = malloc(sizeof(struct rec_io));
    if (this) {
	this->separator[0] = ' ';
	this->separator_length = 1;
	this->fields_count = 0;
    }
    return this;
}

void rec_io_destroy(struct rec_io * this) {
    free (this);
}

void rec_io_set_separator(struct rec_io * this, const char * begin, const char * end) {
    int i;
    for(i = 0; i < MAX_SEPARATOR_LENGTH && begin != end; ++i, ++begin)
	this->separator[i] = *begin;
    this->separator_length = i;
}

static int check_separator(const char * begin, const char * end,
			   const char * sep_begin, const char * sep_end) {
    if (end - begin < sep_end - sep_begin)
	return 0;
    while (sep_begin != sep_end) {
	if (*sep_begin != *begin)
	    return 0;
	++begin;
	++sep_begin;
    }
    return 1;
}

int rec_io_read_record(struct rec_io * this, const char * begin, const char * end) {
    this->fields_count = 0;
    char * input_p = this->input;
    const char * c = begin;
    while (c != end) {
	if (check_separator(c, end, this->separator, this->separator + this->separator_length)) {
	    this->fields[this->fields_count] = input_p;
	    c += this->separator_length;
	    this->fields_count += 1;
	} else {
	    *input_p++ = *c++;
	}
    }
    this->fields[this->fields_count] = input_p;
    this->fields_count += 1;
    return this->fields_count;
}

size_t rec_io_write_record(struct rec_io * this, char * out, size_t maxlen, const char * format) {
    size_t i = 0;
    while (*format != 0 && i < maxlen) {
	if (*format == '%') {
	    unsigned int n = 0;
	    for (++format; *format >= '0' and *format <= '9'; ++format)
		n = n * 10 + *format - '0';
	    if (n < this->fields_count) {
		/* ... */
	    }
	} else {
	    out[i++] = *format++;
	}
    }
    return i;
}