#!/bin/sh
# speedwm-sxp

# some functions we can use on demand
print_text() { printf "%s\n%s\nClear\nRemove\nExit" "$(grep -ve '^$' $CUSTOM_HISTFILE)" "------"; } # function which returns history
print_menu() { OP="$(print_text | "$RUNLAUNCHER" -g 1 -l 40 -p "$*")"; } # function which prints the menu

# basic variables
[ -z "$CUSTOM_HISTFILE" ] && CUSTOM_HISTFILE="$HOME/.config/speedwm/.custom_history"
[ -z "$RUNLAUNCHER" ] && RUNLAUNCHER="spmenu"

# make sure $CUSTOM_HISTFILE exists
mkdir -p "$(dirname "$CUSTOM_HISTFILE")"; touch "$CUSTOM_HISTFILE"

# parse current expression
parse() {
    print_menu "$@"
    case "$OP" in
        "Clear") rm -f "$CUSTOM_HISTFILE"; mkdir -p "$(dirname "$CUSTOM_HISTFILE")"; touch "$CUSTOM_HISTFILE"; main "$@" ;;
        "Exit") exit 0 ;;
        "------") exit 0 ;;
        "") exit 0 ;;
    esac
}

main() {
    parse "Enter an S expression:"
    [ "$OP" = "Remove" ] && \
        remove_entry "$@" || \
        perf_entry "$@"

    return 0
}

# write expression
perf_entry() {
    file_contents="$(grep -v "$OP" "$CUSTOM_HISTFILE")"
    printf "%s\n" "$file_contents" > "$CUSTOM_HISTFILE" # prevent duplicates

    # add entry
    printf "%s\n" "$OP" >> "$CUSTOM_HISTFILE"
    printf "%s\n" "$OP"
}

# write expression
remove_entry() {
    # print menu again so we can choose an entry to remove
    parse "Remove:"
    [ "$OP" = "Remove" ] && remove_entry "$@"

    # add everything except the entry to $file_contents and write that back to the file
    file_contents="$(grep -v "$OP" "$CUSTOM_HISTFILE")" || return 1
    printf "%s\n" "$file_contents" > "$CUSTOM_HISTFILE" || return 1
}

main "$@"