path: root/src/man.c

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

#include "config.h"
#include "cmark.h"
#include "node.h"
#include "buffer.h"

// Functions to convert cmark_nodes to groff man strings.

static void escape_man(strbuf *dest, const unsigned char *source, int length)
{
    int i;
    unsigned char c;

    for (i = 0; i < length; i++) {
        c = source[i];
        if (c == '.' && i == 0) {
            strbuf_puts(dest, "\\&.");
        } else if (c == '\'' && i == 0) {
            strbuf_puts(dest, "\\&'");
        } else if (c == '-') {
            strbuf_puts(dest, "\\-");
        } else if (c == '\\') {
            strbuf_puts(dest, "\\e");
        } else {
            strbuf_putc(dest, source[i]);
        }
    }
}

static inline void cr(strbuf *man)
{
    if (man->size && man->ptr[man->size - 1] != '\n')
        strbuf_putc(man, '\n');
}

struct render_state {
    strbuf* man;
    cmark_node *plain;
};

static int
S_render_node(cmark_node *node, cmark_event_type ev_type, void *vstate)
{
    struct render_state *state = vstate;
    cmark_node *tmp;
    strbuf *man = state->man;
    int list_number;
    bool entering = (ev_type == CMARK_EVENT_ENTER);

    if (state->plain == node) { // back at original node
        state->plain = NULL;
    }

    if (state->plain != NULL) {
        switch(node->type) {
        case CMARK_NODE_TEXT:
        case CMARK_NODE_INLINE_CODE:
        case CMARK_NODE_INLINE_HTML:
            escape_man(man, node->as.literal.data,
                    node->as.literal.len);
            break;

        case CMARK_NODE_LINEBREAK:
        case CMARK_NODE_SOFTBREAK:
            strbuf_putc(man, ' ');
            break;

        default:
            break;
        }
        return 1;
    }

    switch (node->type) {
    case CMARK_NODE_BLOCK_QUOTE:
        if (entering) {
            cr(man);
            strbuf_puts(man, ".RS");
            cr(man);
        } else {
            cr(man);
            strbuf_puts(man, ".RE");
            cr(man);
        }
        break;

    case CMARK_NODE_LIST:
        break;

    case CMARK_NODE_LIST_ITEM:
        if (entering) {
            cr(man);
            strbuf_puts(man, ".IP ");
            if (cmark_node_get_list_type(node->parent) ==
                CMARK_BULLET_LIST) {
                strbuf_puts(man, "\\[bu] 2");
            } else {
                list_number = cmark_node_get_list_start(node->parent);
                tmp = node;
                while (tmp->prev) {
                    tmp = tmp->prev;
                    list_number += 1;
                }
                strbuf_printf(man, "\"%d.\" 4", list_number);
            }
            cr(man);
        } else {
            cr(man);
        }
        break;

    case CMARK_NODE_HEADER:
        if (entering) {
            cr(man);
            strbuf_puts(man,
                    cmark_node_get_header_level(node) == 1 ?
                    ".SH" : ".SS");
            cr(man);
        } else {
            cr(man);
        }
        break;

    case CMARK_NODE_CODE_BLOCK:
        cr(man);
        strbuf_puts(man, ".IP\n.nf\n\\f[C]\n");
        escape_man(man, node->string_content.ptr,
               node->string_content.size);
        cr(man);
        strbuf_puts(man, "\\f[]\n.fi");
        cr(man);
        break;

    case CMARK_NODE_HTML:
        break;

    case CMARK_NODE_HRULE:
        cr(man);
        strbuf_puts(man, ".PP\n  *  *  *  *  *");
        cr(man);
        break;

    case CMARK_NODE_PARAGRAPH:
        if (entering) {
            // no blank line if first paragraph in list:
            if (node->parent &&
                node->parent->type == CMARK_NODE_LIST_ITEM &&
                node->prev == NULL) {
                // no blank line or .PP
            } else {
                cr(man);
                strbuf_puts(man, ".PP\n");
            }
        } else {
            cr(man);
        }
        break;

    case CMARK_NODE_TEXT:
        escape_man(man, node->as.literal.data,
                node->as.literal.len);
        break;

    case CMARK_NODE_LINEBREAK:
        strbuf_puts(man, ".PD 0\n.P\n.PD");
        cr(man);
        break;

    case CMARK_NODE_SOFTBREAK:
        strbuf_putc(man, '\n');
        break;

    case CMARK_NODE_INLINE_CODE:
        strbuf_puts(man, "\\f[C]");
        escape_man(man, node->as.literal.data, node->as.literal.len);
        strbuf_puts(man, "\\f[]");
        break;

    case CMARK_NODE_INLINE_HTML:
        break;

    case CMARK_NODE_STRONG:
        if (entering) {
            strbuf_puts(man, "\\f[B]");
        } else {
            strbuf_puts(man, "\\f[]");
        }
        break;

    case CMARK_NODE_EMPH:
        if (entering) {
            strbuf_puts(man, "\\f[I]");
        } else {
            strbuf_puts(man, "\\f[]");
        }
        break;

    case CMARK_NODE_LINK:
        if (!entering) {
            strbuf_printf(man, " (%s)",
                      cmark_node_get_url(node));
        }
        break;

    case CMARK_NODE_IMAGE:
        if (entering) {
            strbuf_puts(man, "[IMAGE: ");
            state->plain = node;
        } else {
            strbuf_puts(man, "]");
        }
        break;

    default:
        assert(false);
        break;
    }

    // strbuf_putc(man, 'x');
    return 1;
}

char *cmark_render_man(cmark_node *root)
{
    char *result;
    strbuf man = GH_BUF_INIT;
    struct render_state state = { &man, NULL };
    cmark_node *cur;
    cmark_event_type ev_type;
    cmark_iter *iter = cmark_iter_new(root);

    while ((ev_type = cmark_iter_next(iter)) != CMARK_EVENT_DONE) {
        cur = cmark_iter_get_node(iter);
        S_render_node(cur, ev_type, &state);
    }
    result = (char *)strbuf_detach(&man);

    cmark_iter_free(iter);
    strbuf_free(&man);
    return result;
}