#include <stdio.h>
#include <stdlib.h>

#include <errno.h>
#include <string.h>

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>

#include "settings.h"

#include "base85.h"
#include "split.h"
#include "die.h"

#define INFILE		"infile"
#define CHUNKSIZE	(SMTP_MAX_FILESIZE * 4 / 5)

int do_dm_read_invis(dm_sessid_t sid, u8 *handle, size_t hlen, char *buf, int len, dm_off_t start)
{
	int ret;
	int off = 0;

	do {
		ret = dm_read_invis(sid, handle, hlen, DM_NO_TOKEN, start + off, len - off, buf + off);
		if (ret > 0)
			off += ret;
		if (ret <= 0)
			break;
	} while(off < len);

	return (ret < 0 ? ret : off);
}

void dump_buffer(FILE *sendmail, char *buf, char *obuf, int len)
{
	int i;

	len = base85_encode((u8*)buf, (u8*)obuf, len);

	for(i = 0; i < len; ) {
		fprintf(sendmail, "%c", obuf[i++]);
		if (i % 76 == 0)
			fprintf(sendmail, "\n");
	}
	fprintf(sendmail, "\n\n");
}

static inline char bin2hex(u8 u)
{
	if (u >= 10)
		return u - 10 + 'a';
	return u + '0';
}

static void printable_handle(u8 *handle, size_t hlen, char *ascii)
{
	size_t i;

	for(i=0; i<hlen; i++) {
		ascii[i*2]   = bin2hex(handle[i] >> 4);
		ascii[i*2+1] = bin2hex(handle[i] & 0xf);
	}

	ascii[i*2] = '\0';
}

int save_filedata(dm_sessid_t sid, u8 *handle, size_t hlen, dm_size_t fsize)
{
	FILE *sendmail;
	int mbox;
	char *buf, *obuf;
	char asciihandle[HANDLE_MAX_SIZE];
	int len;

	buf = malloc(CHUNKSIZE);
	obuf = malloc(CHUNKSIZE * 5 / 4);
	if (!buf || !obuf) {
		warn("could not allocate buffers");
		return 1;
	}

	printable_handle(handle, hlen, asciihandle);

	for(mbox=0; ; mbox++) {
		/*
		 * Read first to break out of the loop in case we're done
		 */
		len = do_dm_read_invis(sid, handle, hlen, buf, CHUNKSIZE, CHUNKSIZE * mbox);
		if (len <= 0)
			break;

		sendmail = popen(SENDMAIL_PATH " -t \"" SMTP_USER "\"", "w");
		if (!sendmail) {
			warn("could not spawn sendmail");
			return 1;
		}

		fprintf(sendmail, "From " FROM_ADDRESS " / %s\n", asciihandle);
		fprintf(sendmail, "From: " FROM_ADDRESS "\n");
		fprintf(sendmail, "To: " SMTP_USER "\n");
		fprintf(sendmail, "Subject: %s, part %d\n", asciihandle, mbox);
		fprintf(sendmail, "X-DM-Handle: %s\n", asciihandle);
		fprintf(sendmail, "X-DM-Part: %d\n", mbox);
		fprintf(sendmail, "X-DM-Part-Length: %d\n", len);
		fprintf(sendmail, "\n");

		dump_buffer(sendmail, buf, obuf, len);
		fclose(sendmail);
	}

	return 0;
}