/*
 * inline.c:
 * In-line markup.
 *
 *  - URLs are turned into links
 *
 *  - ___ text ___ URL is turned into a link with the given text
 *
 *  - ||| URL alt-text ||| is turned into an <img> tag with the given
 *    alt-text
 *
 *  - *** strong ***
 *
 *  - /// emphasis ///
 *
 *  - ### cite ###
 *
 *  - <>&" are turned into the appropriate HTML escapes.
 *
 *  - \\\ is turned into <br>
 *
 * Copyright (c) 2003 Chris Lightfoot. All rights reserved.
 * Email: chris@ex-parrot.com; WWW: http://www.ex-parrot.com/~chris/
 *
 */

static const char rcsid[] = "$Id: inline.c,v 1.3 2003/06/01 11:39:44 chris Exp $";

#include <assert.h>

#include <stdlib.h>
#include <string.h>

#include "htmlise.h"

static void inline_markup_words(FILE *fp, char **words, const size_t nwords) {
    size_t i;
    int in_strong = 0, in_em = 0, in_cite = 0;

    /* Go through words applying markup. XXX may generate overlapping tags. */
    for (i = 0; i < nwords; ++i) {
        size_t j;

        if (!*words[i])
            continue;
        if (strcmp(words[i], "\\\\\\") == 0)
            fprintf(fp, "<br>");
        else if (strcmp(words[i], "***") == 0) {
            if  (in_strong)
                fprintf(fp, "</strong>");
            else
                fprintf(fp, "<strong>");
            in_strong = !in_strong;
        } else if (strcmp(words[i], "///") == 0) {
            if (in_em)
                fprintf(fp, "</em>");
            else
                fprintf(fp, "<em>");
            in_em = !in_em;
        } else if (strcmp(words[i], "###") == 0) {
            if (in_cite)
                fprintf(fp, "</cite>");
            else
                fprintf(fp, "<cite>");
            in_cite = !in_cite;
        } else if (strcmp(words[i], "|||") == 0) {
            /* Image. Can't have markup inside the alt text. */
            for (j = i + 1; j < nwords && strcmp(words[j], "|||") != 0; ++j);
            if (j < nwords) {
                fprintf(fp, "<img src=\"%s\" alt=\"", words[i + 1]);
                i += 2;
                while (i < j) {
                    fprintf(fp, "%s%s", words[i], i < j ? " " : "");
                    ++i;
                }
/*                ++i;*/
                fprintf(fp, "\">");
            }
        } else if (strncmp(words[i], "http://", 7) == 0 || strncmp(words[i], "ftp://", 6) == 0) 
            fprintf(fp, "<a href=\"%s\">%s</a>", words[i], words[i]);
        else if (strcmp(words[i], "___") == 0) {
            /* Link. */
            for (j = i + 2; j < nwords - 1 && strcmp(words[j], "___") != 0; ++j);
            if (j < nwords - 1) {
                int lastc = 0;
                size_t l;
                
                fprintf(fp, "<a href=\"%s\">", words[j + 1]);

                l = strlen(words[j - 1]) - 1;
                if (strchr("\"`'.,;:()[]?!", words[j - 1][l])) {
                    lastc = words[j - 1][l];
                    words[j - 1][l] = 0;
                }
/*
                while (i < j) {
                    size_t l;
                    if (i == j - 1 && strchr("\"`'.,;:()[]", words[i][l = strlen(words[i]) - 1])) {
                        lastc = words[i][l];
                        words[i][l] = 0;
                    }
                    fprintf(fp, "%s%s", words[i++], i < j ? " " : "");
                }
                ++i;
*/

                inline_markup_words(fp, words + i + 1, j - i - 1);
                fprintf(fp, "</a>");
                if (lastc)
                    putc(lastc, fp);
                i = j + 1;
            }
        } else
            fprintf(fp, "%s", words[i]);

        if (i < nwords - 1)
            putc(' ', fp);
    }
   
}

/* emit_as_html STREAM PARAGRAPH
 * Emit PARAGRAPH to STREAM, converting its text to HTML. */
void emit_as_html(FILE *fp, const struct paragraph *P) {
    static char *buf, **words;
    static size_t buflen, nwordsalloc;
    size_t i, n, nwords = 0;
    const char *p;
    char *q, *ws, *we;

    for (i = 0, n = 0; i < P->nlines; ++i)
        n += strlen(P->lines[i]) + 1;

    /* Conservative; " (1) -> &quot; (5). */
    if (!buf || n * 6 + 1 > buflen)
        buf = realloc(buf, buflen = n * 5 + 1);
    
    for (i = 0, q = buf; i < P->nlines; ++i) {
        for (p = P->lines[i]; *p; ++p) {
            if (*p == '&') {
                strcpy(q, "&amp;");
                q += 5;
            } else if (*p == '<') {
                strcpy(q, "&lt;");
                q += 4;
            } else if (*p == '>') {
                strcpy(q, "&gt;");
                q += 4;
            } else if (*p == '\"') {
                strcpy(q, "&quot;");
                q += 6;
            } else
                *q++ = *p;
        }

        *q++ = '\n';
        
    }
    *q = 0;
    
    /* Break into words. */
    if (!words)
        words = malloc((nwordsalloc = 100) * sizeof *words);

    ws = buf;
    while (1) {
        while (*ws && strchr(" \n", *ws)) ++ws;
        if (!*ws) break;

        /* End of this word. */
        we = ws + strcspn(ws, " \n");
        words[nwords++] = ws;
        if (*we) {
            *we = 0;
            ws = we + 1;
        } else
            break;
        
        if (nwords == nwordsalloc)
            words = realloc(words, (nwordsalloc *= 2) * sizeof *words);
    }

    inline_markup_words(fp, words, nwords);
    
}