#!/bin/bash

cache_dir=/tmp/clipmenu.$USER/

# It's ok that this only applies to the final directory.
# shellcheck disable=SC2174
mkdir -p -m0700 "$cache_dir"

declare -A last_data
declare -A last_filename

while sleep "${CLIPMENUD_SLEEP:-0.5}"; do
    for selection in clipboard primary; do
        if type -p xsel >/dev/null 2>&1; then
            data=$(xsel --"$selection"; printf x)
            # Take ownership of the clipboard, in case the original application
            # is unable to serve the clipboard request (due to being suspended,
            # etc).
            #
            # Primary is excluded from the change of ownership as applications
            # sometimes act up if clipboard focus is taken away from them --
            # for example, urxvt will unhilight text, which is undesirable.
            if [[ $selection != primary ]]; then
                xsel --"$selection" | xsel -i --"$selection"
            fi
        else
            data=$(xclip -o -sel "$selection"; printf x)
            # See above comments about taking ownership of the clipboard for
            # context.
            if [[ $selection != primary ]]; then
                xclip -o -sel "$selection" | xclip -i -sel "$selection"
            fi
        fi

        # We add and remove the x so that trailing newlines are not stripped.
        # Otherwise, they would be stripped by the very nature of how POSIX
        # defines command substitution.
        data=${data%x}

        [[ $data == *[^[:blank:]]* ]] || continue

        [[ ${last_data[$selection]} == "$data" ]] && continue

        # If we were in the middle of doing a selection when the previous poll
        # ran, then we may have got a partial clip.
        possible_partial=${last_data[$selection]}
        if [[ $possible_partial && $data == "$possible_partial"* ]]; then
            rm -- "${last_filename[$selection]}"
        fi

        filename="$cache_dir/$(LC_ALL=C date +%F-%T.%N)"

        last_data[$selection]=$data
        last_filename[$selection]=$filename

        printf '%s' "$data" > "$filename"
    done
done