#!/bin/sh


set -o errexit
set -o nounset


readonly EXIT_SUCCESS=0

readonly NOTES_DIR_BASE="${HOME}/.t"
readonly NOTES_DIR="${NOTES_DIR_BASE}/${NS:-default}"

TAB="$(printf -- '\t')"
readonly TAB


cmd_help() {
    echo "USAGE
    T script for fast notes

    t                            - Show notes in format '[INDEX] NOTE NAME (LINES)'
    t show                       - Show notes in format '[INDEX] NOTE NAME (LINES)'
    t namespaces                 - Show namespaces
    t add (X X X)                - Add note with name X X X
    t edit (INDEX)               - Edit note with INDEX by \$EDITOR
    t delete (INDEX) [INDEX] ... - Delete notes with INDEXes
    t --help                     - Show this message

    t a  - alias to add
    t e  - alias to edit
    t d  - alias to delete
    t ns - alias to namespaces


NAMESPACES
    t namespaces             # show namespaces
    NS=work t a fix bug 211  # add note in workspace 'work'
    NS=work t                # show notes in workspace 'work'"
}


die() {
    echo "$(basename "${0}"): Error: ${1}" 1>&2
    exit "${2:-$EXIT_SUCCESS}"
}

show_notes_with_indexes() {
    SAVEIFS="${IFS}"
    IFS='
'
    index=1
    for note in $(find "${NOTES_DIR}" -maxdepth 1 -type f | sort -n)
    do
        note_lines="$(wc -l < "${note}")"
        if [ "${note_lines}" -gt 70 ]; then
            note_lines="..."
        fi

        printf -- '[%d]\t%s\t(%s)\n' "${index}" "$(basename -- "${note}")" "${note_lines}"
        index="$((index+1))"
    done

    IFS="${SAVEIFS}"
}

_remove_first_and_last_element() {
    cut -d"${TAB}" -f2
}

find_note_name_by_index() {
    note_index="${1}"
    grep "^\[${note_index}\]" | _remove_first_and_last_element
}

cmd_add_note() {
    note="${NOTES_DIR}/$*"
    touch "${note}"
    exit "$EXIT_SUCCESS"
}

cmd_delete_note() {
    current_notes="$(show_notes_with_indexes)"

    for note_index in "$@"
    do
        note="$(echo "${current_notes}" | find_note_name_by_index "${note_index}")"
        note_to_remove="${NOTES_DIR}/${note}"

        if [ ! -f "${note_to_remove}" ]; then
            die "Note with index ${note_index} not found" 1
        fi

        rm "${note_to_remove}"
    done


    exit "$EXIT_SUCCESS"
}

cmd_edit_note() {
    note_index="${1}"
    note="$(show_notes_with_indexes | find_note_name_by_index "${note_index}")"
    note_to_edit="${NOTES_DIR}/${note}"

    if [ ! -f "${note_to_edit}" ]; then
        die "Note with index ${note_index} not found" 1
    fi

    $EDITOR "${note_to_edit}"
    exit "$EXIT_SUCCESS"
}

cmd_cat_note() {
    note_index="${1}"
    note="$(show_notes_with_indexes | find_note_name_by_index "${note_index}")"
    note_to_cat="${NOTES_DIR}/${note}"

    if [ ! -f "${note_to_cat}" ]; then
        die "Note with index ${note_index} not found" 1
    fi

    cat "${note_to_cat}"
    exit "$EXIT_SUCCESS"
}

prettify() {
    column -t -s "${TAB}"
}

cmd_show_namespaces() {
    (
        for ns in $(find "${NOTES_DIR_BASE}/" -mindepth 1 -maxdepth 1 -type d | sort -n)
        do
            namespace_notes_count="$(find "${ns}" -type f | wc -l)"
            printf -- '%s\t(%s)\n' "$(basename "${ns}")" "${namespace_notes_count}"
        done
    ) | prettify
}

cmd_show_notes() {
    show_notes_with_indexes | prettify
}

remove_empty_namespaces() {
    find "${NOTES_DIR_BASE}" -type d -empty -exec rm -r {} \; 2>/dev/null || true
}
trap remove_empty_namespaces EXIT


if [ ! -d "${NOTES_DIR}" ]; then
    mkdir -p "${NOTES_DIR}"
fi


if [ -z "${1+x}" ]; then
    cmd_show_notes
    exit "$EXIT_SUCCESS"
fi


case "${1}" in
    show) shift;           cmd_show_notes       ;;
    ns|namespaces) shift;  cmd_show_namespaces  ;;
    add|a) shift;          cmd_add_note    "$@" ;;
    delete|d) shift;       cmd_delete_note "$@" ;;
    e|edit) shift;         cmd_edit_note   "$@" ;;
    --help) shift;         cmd_help             ;;

    *)                     cmd_cat_note    "$@" ;;
esac
exit "$EXIT_SUCCESS"