/*      $OpenBSD: eqn_html.c,v 1.15 2019/03/17 18:20:07 schwarze Exp $ */
/*
 * Copyright (c) 2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
 * Copyright (c) 2017 Ingo Schwarze <schwarze@openbsd.org>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, 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 <sys/types.h>

#include <assert.h>
#include <ctype.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "mandoc.h"
#include "roff.h"
#include "eqn.h"
#include "out.h"
#include "html.h"

static void
eqn_box(struct html *p, const struct eqn_box *bp)
{
        struct tag      *post, *row, *cell, *t;
        const struct eqn_box *child, *parent;
        const char      *cp;
        size_t           i, j, rows;
        enum htmltag     tag;
        enum eqn_fontt   font;

        if (NULL == bp)
                return;

        post = NULL;

        /*
         * Special handling for a matrix, which is presented to us in
         * column order, but must be printed in row-order.
         */
        if (EQN_MATRIX == bp->type) {
                if (NULL == bp->first)
                        goto out;
                if (bp->first->type != EQN_LIST ||
                    bp->first->expectargs == 1) {
                        eqn_box(p, bp->first);
                        goto out;
                }
                if (NULL == (parent = bp->first->first))
                        goto out;
                /* Estimate the number of rows, first. */
                if (NULL == (child = parent->first))
                        goto out;
                for (rows = 0; NULL != child; rows++)
                        child = child->next;
                /* Print row-by-row. */
                post = print_otag(p, TAG_MTABLE, "");
                for (i = 0; i < rows; i++) {
                        parent = bp->first->first;
                        row = print_otag(p, TAG_MTR, "");
                        while (NULL != parent) {
                                child = parent->first;
                                for (j = 0; j < i; j++) {
                                        if (NULL == child)
                                                break;
                                        child = child->next;
                                }
                                cell = print_otag(p, TAG_MTD, "");
                                /*
                                 * If we have no data for this
                                 * particular cell, then print a
                                 * placeholder and continue--don't puke.
                                 */
                                if (NULL != child)
                                        eqn_box(p, child->first);
                                print_tagq(p, cell);
                                parent = parent->next;
                        }
                        print_tagq(p, row);
                }
                goto out;
        }

        switch (bp->pos) {
        case EQNPOS_TO:
                post = print_otag(p, TAG_MOVER, "");
                break;
        case EQNPOS_SUP:
                post = print_otag(p, TAG_MSUP, "");
                break;
        case EQNPOS_FROM:
                post = print_otag(p, TAG_MUNDER, "");
                break;
        case EQNPOS_SUB:
                post = print_otag(p, TAG_MSUB, "");
                break;
        case EQNPOS_OVER:
                post = print_otag(p, TAG_MFRAC, "");
                break;
        case EQNPOS_FROMTO:
                post = print_otag(p, TAG_MUNDEROVER, "");
                break;
        case EQNPOS_SUBSUP:
                post = print_otag(p, TAG_MSUBSUP, "");
                break;
        case EQNPOS_SQRT:
                post = print_otag(p, TAG_MSQRT, "");
                break;
        default:
                break;
        }

        if (bp->top || bp->bottom) {
                assert(NULL == post);
                if (bp->top && NULL == bp->bottom)
                        post = print_otag(p, TAG_MOVER, "");
                else if (bp->top && bp->bottom)
                        post = print_otag(p, TAG_MUNDEROVER, "");
                else if (bp->bottom)
                        post = print_otag(p, TAG_MUNDER, "");
        }

        if (EQN_PILE == bp->type) {
                assert(NULL == post);
                if (bp->first != NULL &&
                    bp->first->type == EQN_LIST &&
                    bp->first->expectargs > 1)
                        post = print_otag(p, TAG_MTABLE, "");
        } else if (bp->type == EQN_LIST && bp->expectargs > 1 &&
            bp->parent && bp->parent->type == EQN_PILE) {
                assert(NULL == post);
                post = print_otag(p, TAG_MTR, "");
                print_otag(p, TAG_MTD, "");
        }

        if (bp->text != NULL) {
                assert(post == NULL);
                tag = TAG_MI;
                cp = bp->text;
                if (isdigit((unsigned char)cp[0]) ||
                    (cp[0] == '.' && isdigit((unsigned char)cp[1]))) {
                        tag = TAG_MN;
                        while (*++cp != '\0') {
                                if (*cp != '.' &&
                                    isdigit((unsigned char)*cp) == 0) {
                                        tag = TAG_MI;
                                        break;
                                }
                        }
                } else if (*cp != '\0' && isalpha((unsigned char)*cp) == 0) {
                        tag = TAG_MO;
                        while (*cp != '\0') {
                                if (cp[0] == '\\' && cp[1] != '\0') {
                                        cp++;
                                        mandoc_escape(&cp, NULL, NULL);
                                } else if (isalnum((unsigned char)*cp)) {
                                        tag = TAG_MI;
                                        break;
                                } else
                                        cp++;
                        }
                }
                font = bp->font;
                if (bp->text[0] != '\0' &&
                    (((tag == TAG_MN || tag == TAG_MO) &&
                      font == EQNFONT_ROMAN) ||
                     (tag == TAG_MI && font == (bp->text[1] == '\0' ?
                      EQNFONT_ITALIC : EQNFONT_ROMAN))))
                        font = EQNFONT_NONE;
                switch (font) {
                case EQNFONT_NONE:
                        post = print_otag(p, tag, "");
                        break;
                case EQNFONT_ROMAN:
                        post = print_otag(p, tag, "?", "fontstyle", "normal");
                        break;
                case EQNFONT_BOLD:
                case EQNFONT_FAT:
                        post = print_otag(p, tag, "?", "fontweight", "bold");
                        break;
                case EQNFONT_ITALIC:
                        post = print_otag(p, tag, "?", "fontstyle", "italic");
                        break;
                default:
                        abort();
                }
                print_text(p, bp->text);
        } else if (NULL == post) {
                if (NULL != bp->left || NULL != bp->right)
                        post = print_otag(p, TAG_MFENCED, "??",
                            "open", bp->left == NULL ? "" : bp->left,
                            "close", bp->right == NULL ? "" : bp->right);
                if (NULL == post)
                        post = print_otag(p, TAG_MROW, "");
                else
                        print_otag(p, TAG_MROW, "");
        }

        eqn_box(p, bp->first);

out:
        if (NULL != bp->bottom) {
                t = print_otag(p, TAG_MO, "");
                print_text(p, bp->bottom);
                print_tagq(p, t);
        }
        if (NULL != bp->top) {
                t = print_otag(p, TAG_MO, "");
                print_text(p, bp->top);
                print_tagq(p, t);
        }

        if (NULL != post)
                print_tagq(p, post);

        eqn_box(p, bp->next);
}

void
print_eqn(struct html *p, const struct eqn_box *bp)
{
        struct tag      *t;

        if (bp->first == NULL)
                return;

        t = print_otag(p, TAG_MATH, "c", "eqn");

        p->flags |= HTML_NONOSPACE;
        eqn_box(p, bp);
        p->flags &= ~HTML_NONOSPACE;

        print_tagq(p, t);
}