#!/bin/bash

_help() {
    echo "Pass arguments to create a static version of the index, printed on stdout
    Templating will replace config values  config.style and config.source to null

    -l [snippets.txt]   Path to snippets.txt.  must be passed
    -c [config.js]   *Path to configuration js replacing config values
    -s [styles.css]  *Path to extra styles

    * can be left out
    "
    exit
}

_checkenv() {
    if [[ ! -e "$SNIPPETS" ]]; then
        echo "Snippets file '$SNIPPETS' not found."
        _help
        exit 1
    fi
    if [[ -n "$CONFIG" ]]; then
        if [[ ! -e "$CONFIG" ]]; then
            echo "Config file '$CONFIG' not found."
            exit 1
        fi
    fi
    if [[ -n "$STYLE" ]]; then
        if [[ ! -e "$STYLE" ]]; then
            echo "Styles file '$STYLE' not found."
            exit 1
        fi
    fi

    echo "
    Snippets file: $SNIPPETS
    Config file: $CONFIG
    Style file: $STYLE
    " >&2

}
_replace_snippets() {
    if [[ -e "$SNIPPETS" ]]; then
        sniptmp=$( mktemp )
        sed 's/`/\\`/g' "$SNIPPETS" > "$sniptmp"
        sed \
        -e '/TEMPLATED:SNIPPETS/a config.source=null;' \
        -e '/TEMPLATED:SNIPPETS/a config.snippets=`' \
        -e "/TEMPLATED:SNIPPETS/r $sniptmp" \
        -e '/TEMPLATED:SNIPPETS/a `;'
        #-e "/TEMPLATED:SNIPPETS/d"
        rm -f "$sniptmp"
    else
        cat -
    fi
}
_replace_config() {
    if [[ -e "$CONFIG" ]]; then
        sed \
        -e "/TEMPLATED:CONFIG/r $CONFIG" \
        -e "/^.script language.*config.js.*script.*/d"
        #-e "/TEMPLATED:CONFIG/d"
    else
        cat -
    fi
}
_replace_style() {
    if [[ -e "$STYLE" ]]; then
        sed \
        -e "/TEMPLATED:STYLE/r $STYLE" \
        -e '/TEMPLATED:CONFIG/a config.style=null;' \
        #-e "/TEMPLATED:STYLE/d"
    else
        cat -
    fi
}
_inject_dependencies() {

    sed \
        -e "/TEMPLATED:HIGHLIGHT_STYLE/r $SELFDIR/default.min.css" \
        -e "/TEMPLATED:HIGHLIGHT_STYLE/r $SELFDIR/dark.min.css" \
        -e "/TEMPLATED:HIGHLIGHT_CODE/r $SELFDIR/highlight.min.js" \
        -e "/stylesheet.*default.min.css/d" \
        -e "/stylesheet.*dark.min.css/d" \
        -e "/script.*highlight.min.js/d"

}
_replace() {
    cat "$SELFDIR"/index.html | _replace_snippets | _replace_style | _replace_config | _inject_dependencies
}

SELFDIR=$( dirname $( readlink -f "$0") )
CONFIG=
STYLE=
SNIPPETS=

for (( i=1; i<=$#; i++ )); do
  j=$(( i + 1 ))
  [[ "${!i}" = "-h" ]] && _help
  [[ "${!i}" = "--help" ]] && _help
  [[ "${!i}" = "-l" ]] && { SNIPPETS="${!j}"; shift 1; continue; }
  [[ "${!i}" = "-c" ]] && { CONFIG="${!j}"; shift 1; continue; }
  [[ "${!i}" = "-s" ]] && { STYLE="${!j}"; shift 1; continue; }
done

_checkenv
_replace