Begin an sh impl

2 files changed, 141 insertions, 1 deletions

@@ -41,7 +41,10 @@ BEGIN { # configuration
                 linefmt["header", 3] = "<h3>%s</h3>\n"
                 isblock["link"] = 0
                 linefmt["link"] = "<a href=\"%s\">%s</a>\n"
-                # escapes
+                # escapes -- TODO: rethink these.
+                ## I think the best solution is to have a pair of arrays --
+                ## esc_orig and esc_repl.  These will have keys in the
+                ## [n, block] format to keep them straight.
                 esc["verbatim", 0, "&"] = "\\&amp;"
                 esc["verbatim", 8, "<"] = "\\&lt;"
                 esc["verbatim", 9, ">"] = "\\&gt;"
@@ -0,0 +1,137 @@
+#!/bin/sh
+
+BLOCK=
+BUFFER=
+
+process() {
+        while read -r LINE
+        do
+                if test "$BLOCK" = verbatim
+                then
+                        printf '%s\n' "$LINE"
+                        continue
+                fi
+
+                set -- $LINE
+
+                case "$LINE" in
+                        ('```')
+                                if test "$BLOCK" = verbatim
+                                then BLOCK=
+                                else BLOCK=verbatim
+                                fi
+                                ;;
+                        ('')
+                                if test "$BLOCK" = verbatim
+                                then bufpush $'\n'
+                                else bufclose
+                                fi
+                                ;;
+                        ('=>'*) link "$@" ;;
+                        ('#'*) header "$@" ;;
+                        ('*'*) shift; blknew list "$*" ;;
+                        ('>'*) shift; blknew quote "$*" ;;
+                        (*) shift; blknew paragraph "$*" ;;
+                esac
+        done
+        bufclose
+}
+
+blknew() {
+        test "$BLOCK" = "$1" || bufclose
+        bufpush "$(printf "$(eval echo "\$format_$BLOCK")" "$@")"
+        BLOCK="$1"
+}
+
+bufclose() {
+        if test -z "$BLOCK"
+        then "$COLLAPSE_BLANKS" && return
+        else newline; return
+        fi
+
+        # blockp "$BLOCK" || return
+        # fillp $BLOCK && buffill "$(fillp $BLOCK)"
+
+        # TODO: escape shit
+
+        printf '%s%s%s\n' \
+               "$(echo eval "\$opener_$BLOCK")" \
+               "$BUFFER" \
+               "$(echo eval "\$closer_$BLOCK")"
+
+        BLOCK=
+}
+
+buffill() { # buffill WIDTH
+        if test $1 -lt 0
+        then BUFFER="$(printf '%s\n' "$BUFFER" | tr '\n' ' ')"
+        else
+                out=
+                nline=0
+                printf '%s\n' "$BUFFER" | sed 's/[ \t]\+/\n/g' |
+                        while read -r word
+                        do
+                                if test $((nline + ${#word})) -ge "$1"
+                                then
+                                        out="${out}"${out:+$'\n'}"${word}"
+                                        nline=${#word}
+                                else
+                                        out="${out}${out:+ }${word}"
+                                        nline=$((nline + ${#word} + 1))
+                                fi
+                        done
+                BUFFER="$out"
+        fi
+}
+
+bufpush() { BUFFER="${BUFFER}$@"; }
+
+fillp() {
+        :
+}
+
+header() {
+        bufclose
+        lvl=${#1}; shift
+        bufpush "$(printf "$(eval echo "\$format_h$lvl")" "$*")"
+        BLOCK=header
+}
+
+link() {
+        url="$2"; shift 2
+        if test "$BLOCK" = paragraph #&& ! blockp link
+        then bufpush "$(printf "$format_link" "$url" "$*")"
+        else blknew linklist "$url" "$*"
+        fi
+}
+
+newline() { printf '\n'; }
+
+html() {
+        format_link='<a href="%s">%s</a>\n'
+        format_h1='<h1>%s</h1>\n'
+        format_h2='<h2>%s</h2>\n'
+        format_h3='<h3>%s</h3>\n'
+        opener_verbatim='<pre><code>'
+        closer_verbatim='</code></pre>\n'
+        format_verbatim='%s\n'
+        opener_paragraph='<p>'
+        closer_paragraph='</p>\n'
+        format_paragraph='%s\n'
+        opener_quote='<blockquote>'
+        closer_quote='</blockquote>\n'
+        format_quote='%s\n'
+        opener_list='<ul>\n'
+        closer_list='</ul>\n'
+        format_list='<li>%s</li>'
+        opener_linklist='<ul class="linklist">'
+        closer_linklist='</ul>'
+        format_linklist="$(printf "$format_list" "$format_link")"
+}
+
+main() {
+        html
+        process "$@"
+}
+
+main "$@"