#!/bin/sh
# speedwm-sxp

# some functions we can use on demand
print_text() { printf "%s\n%s\nClear\nRemove\nExit\n" "$(cat "$CUSTOM_HISTFILE")" "------"; } # function which returns history
print() { 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 "$@"
    [ "$OP" = "Clear" ] && printf "" > "$CUSTOM_HISTFILE" && exit
    [ "$OP" = "Exit" ] && exit 0
    [ "$OP" = "------" ] && exit 0
    [ -z "$OP" ] && exit 0
}

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

    return 0
}

# write expression
add_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 "$@"