Basic: fix errors, reader, if form. Self-host 0-3

[jackhill/mal.git] / basic / qb2cbm.sh

#!/bin/bash

set -e

DEBUG=${DEBUG:-}
KEEP_REM=${KEEP_REM:-1}
# 0 - drop all REMs
# 1 - keep LABEL and INCLUDE REMs (and blank lines)
# 2 - keep LABEL, INCLUDE, and GOTO REMs
# 3 - keep LABEL, INCLUDE, GOTO, and whole line REMs
# 4 - keep all REMS (end of line REMs too)

infile=$1

die () {
    echo >&2 "$*"
    exit 1
}

[ "${infile}" ] || die "Usage: <infile>"

input=$(cat ${infile})

[ "${DEBUG}" ] && echo >&2 "Processing includes"

full="${input}"
declare -A included

while [[ ${input} =~ REM\ \$INCLUDE:\ \'.*\' ]]; do
    full=""
    while read -r line; do
        if [[ ${line} =~ REM\ \$INCLUDE:\ \'.*\' ]]; then
            include=${line#REM \$INCLUDE: \'}
            include=${include%\'}
            # Only include it once
            if [ "${included[${include}]}" ];then
                [ "${DEBUG}" ] && echo >&2 "already included: ${include}"
                continue
            fi
            [ "${DEBUG}" ] && echo >&2 "including: ${include}"
            included[${include}]="done"
            if [ "${KEEP_REM}" -ge 1 ]; then
                full="${full}\nREM vvv BEGIN '${include}' vvv\n$(cat ${include})\nREM vvv END '${include}' vvv\n"
            else
                full="${full}\n$(cat ${include})\n"
            fi
        else
            full="${full}${line}\n"
        fi
    done < <(echo -e "${input}")
    input="${full}"
done


[ "${DEBUG}" ] && echo >&2 "Renumbering"

data=""
declare -A labels

lnum=1
while read -r line; do
    if [[ ${line} =~ ^\ *# ]]; then
        [ "${DEBUG}" ] && echo >&2 "ignoring # style comment at $lnum"
        continue
    elif [[ "${KEEP_REM}" -lt 3 && ${line} =~ ^\ *REM && \
            ! ${line} =~ REM\ vvv && ! ${line} =~ REM\ ^^^ ]]; then
        [ "${DEBUG}" ] && echo >&2 "dropping REM comment: ${line}"
        continue
    elif [[ ${line} =~ ^\ *$ ]]; then
        if [ "${KEEP_REM}" -ge 1 ]; then
            [ "${DEBUG}" ] && echo >&2 "found blank line at $lnum"
            data="${data}\n"
        else
            [ "${DEBUG}" ] && echo >&2 "ignoring blank line at $lnum"
        fi
        continue
    elif [[ ${line} =~ ^[A-Za-z_][A-Za-z0-9_]*:$ ]]; then
        label=${line%:}
        [ "${DEBUG}" ] && echo >&2 "found label ${label} at $lnum"
        labels[${label}]=$lnum
        if [ "${KEEP_REM}" -ge 1 ]; then
            data="${data}${lnum} REM ${label}:\n"
        else
            continue
        fi
    else
        data="${data}${lnum} ${line}\n"
    fi
    lnum=$(( lnum + 1 ))
done < <(echo -e "${input}")

if [[ "${KEEP_REM}" -lt 4 ]]; then
    [ "${DEBUG}" ] && echo >&2 "Dropping line ending REMs"
    data=$(echo -e "${data}" | sed "s/: REM [^\n]*$//")
fi

for label in "${!labels[@]}"; do
    [ "${DEBUG}" ] && echo >&2 "Updating label: ${label}"
    lnum=${labels[${label}]}
    if [ "${KEEP_REM}" -ge 2 ]; then
        data=$(echo "${data}" | sed "s/\(THEN\|GOTO\|GOSUB\) ${label}\>/\1 ${lnum}: REM ${label}/g")
    else
        data=$(echo "${data}" | sed "s/\(THEN\|GOTO\|GOSUB\) ${label}\>/\1 ${lnum}/g")
    fi
done

echo -e "${data}"