/* (C) Copyright 1993,1994 by Carnegie Mellon University
 * All Rights Reserved.
 *
 * Permission to use, copy, modify, distribute, and sell this software
 * and its documentation for any purpose is hereby granted without
 * fee, provided that the above copyright notice appear in all copies
 * and that both that copyright notice and this permission notice
 * appear in supporting documentation, and that the name of Carnegie
 * Mellon University not be used in advertising or publicity
 * pertaining to distribution of the software without specific,
 * written prior permission.  Carnegie Mellon University makes no
 * representations about the suitability of this software for any
 * purpose.  It is provided "as is" without express or implied
 * warranty.
 *
 * CARNEGIE MELLON UNIVERSITY DISCLAIMS ALL WARRANTIES WITH REGARD TO
 * THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS, IN NO EVENT SHALL CARNEGIE MELLON UNIVERSITY BE LIABLE
 * FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */
#include <stdio.h>
#include <string.h>
#include <stdlib.h>

extern char *magic_look();
extern char *os_genid();
extern char *md5digest();

#define NUMREFERENCES 4

/*
 * Encode a file into one or more MIME messages, each
 * no larger than 'maxsize'.  A 'maxsize' of zero means no size limit.
 * If 'applefile' is non-null, it is the first part of a multipart/appledouble
 * pair.
 */
int encode(FILE *infile, FILE *applefile, char *fname, FILE *descfile, char *subject, char *headers, long maxsize, char *typeoverride, char *outfname)
{
    char *type;
    FILE *outfile;
    char *cleanfname, *p;
    char *digest, *appledigest;
    long filesize, l, written;
    int thispart, numparts = 1;
    int wrotefiletype = 0;
    char *multipartid, *msgid, *referenceid[NUMREFERENCES];
    char buf[1024];
    int i;

    /* Clean up fname for printing */
    cleanfname = fname;
#ifdef __riscos
    /* This filename-cleaning knowledge will probably
     * be moved to the os layer in a future version.
     */
    if (p = strrchr(cleanfname, '.')) cleanfname = p+1;
#else
    if (p = strrchr(cleanfname, '/')) cleanfname = p+1;
    if (p = strrchr(cleanfname, '\\')) cleanfname = p+1;
#endif
    if (p = strrchr(cleanfname, ':')) cleanfname = p+1;

    /* Find file type */
    if (typeoverride) {
        type = typeoverride;
    }
    else {
        type = magic_look(infile);
    }

    /* Compute MD5 digests */
    digest = md5digest(infile, &filesize);
    if (applefile) {
        appledigest = md5digest(applefile, &l);
        filesize += l;
    }

    /* See if we have to do multipart */
    if (maxsize) {
        filesize = (filesize / 54) * 73; /* Allow for base64 expansion */

        /* Add in size of desc file */
        if (descfile) {
            free(md5digest(descfile, &l));      /* XXX */
            filesize += l;
        }

        numparts = (filesize-1000)/maxsize + 1;
        if (numparts < 1) numparts = 1;
    }

    multipartid = os_genid();
    for (i=0; i<NUMREFERENCES; i++) {
        referenceid[i] = 0;
    }

    for (thispart=1; thispart <= numparts; thispart++) {
        written = 0;

        /* Open output file */
        if (numparts == 1) {
            outfile = fopen(outfname, "w");
            if (!outfile) os_perror(outfname);
        }
        else {
#ifdef __riscos
            /* Arrgh, riscos uses '.' as directory separator */
            sprintf(buf, "%s/%02d", outfname, thispart);
#else
            sprintf(buf, "%s.%02d", outfname, thispart);
#endif
            outfile = fopen(buf, "w");
            if (!outfile) os_perror(buf);
        }
        if (!outfile) return 1;
        
        msgid = os_genid();
        fprintf(outfile, "Message-ID: <%s>\n", msgid);
        fprintf(outfile, "Mime-Version: 1.0\n");
        if (headers) fputs(headers, outfile);
        if (numparts > 1) {
            fprintf(outfile, "Subject: %s (%02d/%02d)\n", subject,
                    thispart, numparts);
            if (thispart == 1) {
                referenceid[0] = msgid;
            }
            else {
                /* Put out References: header pointing to previous parts */
                fprintf(outfile, "References: <%s>\n", referenceid[0]);
                for (i=1; i<NUMREFERENCES; i++) {
                    if (referenceid[i]) fprintf(outfile, "\t <%s>\n",
                                                referenceid[i]);
                }
                for (i=2; i<NUMREFERENCES; i++) {
                    referenceid[i-1] = referenceid[i];
                }
                referenceid[NUMREFERENCES-1] = msgid;
            }
            fprintf(outfile,
                    "Content-Type: message/partial; number=%d; total=%d;\n",
                    thispart, numparts);
            fprintf(outfile, "\t id=\"%s\"\n", multipartid);
            fprintf(outfile, "\n");
        }

        if (thispart == 1) {
            if (numparts > 1) {
                fprintf(outfile, "Message-ID: <%s>\n", multipartid);
                fprintf(outfile, "MIME-Version: 1.0\n");
            }
            fprintf(outfile, "Subject: %s\n", subject);
            fprintf(outfile,
                    "Content-Type: multipart/mixed; boundary=\"-\"\n");
            fprintf(outfile,
"\nThis is a MIME encoded message.  Decode it with \"munpack\"\n");
            fprintf(outfile,
"or any other MIME reading software.  Mpack/munpack is available\n");
            fprintf(outfile,
"via anonymous FTP in ftp.andrew.cmu.edu:pub/mpack/\n");
            written = 300;

            /* Spit out description section */
            if (descfile) {
                fprintf(outfile, "---\n\n");
                while (fgets(buf, sizeof(buf), descfile)) {
                    /* Strip multiple leading dashes as they may become MIME
                     * boundaries
                     */
                    p = buf;
                    if (*p == '-') {
                        while (p[1] == '-') p++;
                    }

                    fputs(p, outfile);
                    written += strlen(p);
                }
                fprintf(outfile, "\n");
            }
    
            fprintf(outfile, "---\n");

            if (applefile) {
                fprintf(outfile,
        "Content-Type: multipart/appledouble; boundary=\"=\"; name=\"%s\"\n",
                        cleanfname);
                fprintf(outfile,
                        "Content-Disposition: inline; filename=\"%s\"\n",
                        cleanfname);
                fprintf(outfile, "\n\n--=\n");
                fprintf(outfile, "Content-Type: application/applefile\n");
                fprintf(outfile, "Content-Transfer-Encoding: base64\n");
                fprintf(outfile, "Content-MD5: %s\n\n", appledigest);
                free(appledigest);
                written += 100;
            }

        }

        if (applefile && !feof(applefile)) {
            if (written == maxsize) written--; /* avoid a nasty fencepost error */
            written += to64(applefile, outfile,
                            (thispart == numparts) ? 0 : (maxsize-written));

            if (!feof(applefile)) {
                if (outfile) fclose(outfile);
                continue;
            }

            fprintf(outfile, "\n--=\n");
        }


        if (!wrotefiletype++) {
            fprintf(outfile, "Content-Type: %s; name=\"%s\"\n", type,
                    cleanfname);
            fprintf(outfile, "Content-Transfer-Encoding: base64\n");
            fprintf(outfile, "Content-Disposition: inline; filename=\"%s\"\n",
                    cleanfname);
            fprintf(outfile, "Content-MD5: %s\n\n", digest);
            free(digest);
            written += 80;
        }

        if (written == maxsize) written--; /* avoid a nasty fencepost error */

        written += to64(infile, outfile,
                        (thispart == numparts) ? 0 : (maxsize-written));

        if (thispart == numparts) {
            if (applefile) fprintf(outfile, "\n--=--\n");
            fprintf(outfile, "\n-----\n");
        }
        
        if (outfile) fclose(outfile);
    }

    return 0;
}