q.sh/q

#!/bin/sh
#
# Distributed under the terms of the BSD License
#
# Copyright (c) 2021, Konstantin Nazarov <mail@knazarov.com>
# All rights reserved.
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are met:
#
# 1. Redistributions of source code must retain the above copyright notice, this
#    list of conditions and the following disclaimer.
#
# 2. Redistributions in binary form must reproduce the above copyright notice,
#    this list of conditions and the following disclaimer in the documentation
#    and/or other materials provided with the distribution.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
# DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
# SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
# CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
# OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

set -e

ENV_fzf=fzf
ENV_find=find
ENV_awk=awk
ENV_q=~/.config/q.sh

SELF=$(cd -P -- "$(dirname -- "$0")" && printf '%s\n' "$(pwd -P)/$(basename -- "$0")")

if [[ -z "$Q_SCRIPT_DIR" ]]; then
    Q_SCRIPT_DIR="$ENV_q"
fi

INDEX_FILE=~/.q.index
HINT_FILE=~/.q.hints

new_scripts_exist() {
    if [[ ! -d "$Q_SCRIPT_DIR" ]]; then
        return 0
    fi

    if [[ ! -s "$INDEX_FILE" ]]; then
        return 0
    fi

    NEWER_FILES="$($ENV_find "$Q_SCRIPT_DIR" -name "q-*" -newer "$INDEX_FILE")"

    if [[ -z "$NEWER_FILES" ]]; then
        return 1
    fi

    return 0
}

rebuild_index() {
    if [[ ! -d "$Q_SCRIPT_DIR" ]]; then
        return
    fi

    pushd "$Q_SCRIPT_DIR" >/dev/null
    $ENV_find . -type f -name 'q-*' | while read -r FN
    do
        FILENAME="$(echo "$FN" | sed 's/^\.\///g')"

        "$Q_SCRIPT_DIR/$FILENAME" | while read -r line
        do
            echo "/$line/ {print \"$FILENAME\"}"
        done
    done
    popd > /dev/null
}

rebuild_hints() {
    if [[ ! -d "$Q_SCRIPT_DIR" ]]; then
        return
    fi

    pushd "$Q_SCRIPT_DIR" >/dev/null
    $ENV_find . -type f -name 'q-*' | while read -r FN
    do
        FILENAME="$(echo "$FN" | sed 's/^\.\///g')"

        "$Q_SCRIPT_DIR/$FILENAME" --hint
    done
    popd > /dev/null
}

get_scripts_for_cmd() {
    if [[ ! -f "$INDEX_FILE" ]]; then
        return
    fi

    echo "$1" | $ENV_awk -f "$INDEX_FILE" | while read -r line
    do
        echo "$line"
    done
}

complete_command() {
    COMMAND="$@"
    SCRIPTS="$(get_scripts_for_cmd "$COMMAND")"
    if [ -z "$SCRIPTS" ] || \
       [ "$(echo "$SCRIPTS" | wc -w)" -gt "1" ]; then
        cat "$HINT_FILE"
        exit 0
    fi
    "$Q_SCRIPT_DIR/$SCRIPTS" --complete "$@"
}

run_command() {
    COMMAND="$@"
    FIRST=${COMMAND%%" "*}
    REST=${COMMAND#*" "}
    SCRIPTS="$(get_scripts_for_cmd "$REST")"
    if [ -z "$SCRIPTS" ] || \
       [ "$(echo "$SCRIPTS" | wc -w)" -gt "1" ]; then
        echo "Scripts matched: $SCRIPTS"
        exit 0
    fi
    "$Q_SCRIPT_DIR/$SCRIPTS" --run "$FIRST" "$REST"
}

run_command_cli() {
    COMMAND="$@"
    SCRIPTS="$(get_scripts_for_cmd "$COMMAND")"
    if [ -z "$SCRIPTS" ] || \
       [ "$(echo "$SCRIPTS" | wc -w)" -gt "1" ]; then
        echo "Scripts matched: $SCRIPTS"
        exit 0
    fi
    "$Q_SCRIPT_DIR/$SCRIPTS" --cli "$COMMAND"
}

preview_command() {
    COMMAND="$@"
    FIRST=${COMMAND%%" "*}
    REST=${COMMAND#*" "}
    SCRIPTS="$(get_scripts_for_cmd "$REST")"
    if [ -z "$SCRIPTS" ] || \
       [ "$(echo "$SCRIPTS" | wc -w)" -gt "1" ]; then
        echo "Scripts matched: $SCRIPTS"
        exit 0
    fi
    "$Q_SCRIPT_DIR/$SCRIPTS" --preview "$FIRST" "$REST"
}

if [[ ! -f "$INDEX_FILE" ]] || new_scripts_exist; then
    rebuild_index > "$INDEX_FILE"
    rebuild_hints > "$HINT_FILE"
fi

while (( "$#" )); do
    case "$1" in
        -c|--complete)
            shift
            complete_command "$@"
            exit 0
            ;;
        -r|--run)
            shift
            if [[ -z "$@" ]]; then
                exit 0
            fi
            run_command "$@"
            exit 0
            ;;
        -p|--preview)
            shift
            if [[ -z "$@" ]]; then
                exit 0
            fi
            preview_command "$@"
            exit 0
            ;;
        -u|--update)
            shift
            rebuild_index > "$INDEX_FILE"
            rebuild_hints > "$HINT_FILE"
            exit 0
            ;;
        *)
            break
            ;;
    esac
done


COMMAND="$@"

if [[ -z "$COMMAND" ]] && [[ ! -t 0 ]]; then
    COMMAND="$(cat)"
fi

if [[ -z "$COMMAND" ]]; then
    PREF="$SELF -c"
    INITIAL=""
    FZF_DEFAULT_COMMAND="$PREF '$INITIAL'" $ENV_fzf \
        --bind "change:reload-sync:$PREF {q} || true" \
        --ansi --query "$INITIAL" \
        --preview "$SELF -p {}" \
        --with-nth="2..-1" \
        --preview-window wrap \
        --tiebreak=index | xargs -o "$SELF" -r
else
    run_command_cli "$COMMAND"
fi