#!/bin/bash
#  $HeadURL$ $LastChangedRevision$

#  Modules
. $(miniade) || { echo "${0##*/}: ERROR: miniade failed (hint: run 'miniade' to see error)" >&2; exit 1; }
. <(rdw2-config --format=shell) || { echo "${0##*/}: INTERNAL ERROR: failed to run rdw2-config" >&2; exit 3; }

#  Configurable stuff

#  Other globals

main()
{
    local MY_ARGS
    local MODE LABEL_TYPE LABELEE PROGNAME

    #  Defaults for options
    HOST=
    FORCE_FLAG=false

    #  Process options
    special_opts_handler()
    {
        case $1 in
            --host=*) HOST=${1#*=} ;;
            --force)  FORCE_FLAG=true ;;
            *)        return 1 ;;
        esac
    }
    miniade_process_options --help-handler=help --special-opts-handler=special_opts_handler MY_ARGS "$@" && set -- "${MY_ARGS[@]}"

    #  Process arguments
    [ $# -ge 3 ] || miniade_bad_usage
    MODE=$1
    LABEL_TYPE=$2
    LABELEE=$3
    shift 3
    miniade_debug 2 "main: MODE=$MODE, LABEL_TYPE=$LABEL_TYPE, LABELEE=$LABELEE"

    #  Sanity checks and derivations
    [[ $MODE =~ ^(add|verify|is-labelled|read|delete|touch)$ ]] || miniade_bad_usage
    [[ $LABEL_TYPE =~ ^(medium|client|server|session|dle)$ ]] || miniade_bad_usage
    miniade_get_progname PROGNAME
    DB_FILE=$HOME/.$PROGNAME.sqlite

    #  Guts
    #  (delegated)
    mode_${MODE//-/_} "$@"
}

help()
{
    local PROGNAME

    miniade_get_progname PROGNAME
    echo "Usage: $PROGNAME [ <options> ] add    <label-type> <labelee> <desired-label>"
    echo "       $PROGNAME [ <options> ] verify <label-type> <labelee> <expected-label>"
    echo "       $PROGNAME [ <options> ] is-labelled <label-type> <labelee>"
    echo "       $PROGNAME [ <options> ] read <label-type> <labelee>"
    echo "       $PROGNAME [ <options> ] delete <label-type> <labelee> <expected-label>"
    echo "       $PROGNAME [ <options> ] touch <label-type> <labelee> <expected-label>"
    echo
    echo "<label-type>: client, dle, medium, session"
    echo
    exit 0
}

mode_add()
{
    [ $# = 1 ] || miniade_bad_usage 
    DESIRED_LABEL=$1
    [[ $DESIRED_LABEL =~ ^.{8}-.{4}-.{4}-.{4}-.{12}$ ]] || miniade_error "$DESIRED_LABEL: invalid label (hint: run 'uuidgen' to see what valid labels look like)"

    create_tables
    sqlite3 $DB_FILE "INSERT OR FAIL INTO labels VALUES ('$LABEL_TYPE', '$LABELEE', '$DESIRED_LABEL', $(date +%s));"
}

mode_verify()
{
    local EXPECTED_LABEL ACTUAL_LABEL

    [ $# = 1 ] || miniade_bad_usage 
    EXPECTED_LABEL=$1
    [[ $EXPECTED_LABEL =~ ^.{8}-.{4}-.{4}-.{4}-.{12}$ ]] || miniade_error "$EXPECTED_LABEL: invalid label (hint: run 'uuidgen' to see what valid labels look like)"

    create_tables
    mode_read > /dev/null
    ACTUAL_LABEL=$(sqlite3 $DB_FILE "SELECT label FROM labels WHERE type = '$LABEL_TYPE' AND labelee = '$LABELEE';")

    [ "X$EXPECTED_LABEL" = "X$ACTUAL_LABEL" ] || miniade_error "$LABEL_TYPE has wrong label (expected: $EXPECTED_LABEL; found: $ACTUAL_LABEL)"
}

mode_is_labelled()
{
    [ $# = 0 ] || miniade_bad_usage 

    mode_read > /dev/null
    ACTUAL_LABEL=$(sqlite3 $DB_FILE "SELECT label FROM labels WHERE type = '$LABEL_TYPE' AND labelee = '$LABELEE';")
    [[ $ACTUAL_LABEL =~ ^.{8}-.{4}-.{4}-.{4}-.{12}$ ]] || miniade_error "$LABEL_TYPE: has corrupted label"
}

mode_read()
{
    local ACTUAL_LABEL

    [ $# = 0 ] || miniade_bad_usage 

    create_tables
    ACTUAL_LABEL=$(sqlite3 $DB_FILE "SELECT label FROM labels WHERE type = '$LABEL_TYPE' AND labelee = '$LABELEE';") || miniade_error "failed to read label"
    [ "X$ACTUAL_LABEL" != X ] || miniade_error "unlabelled"
    echo "$ACTUAL_LABEL"
}

mode_delete()
{
    [ $# = 1 ] || miniade_bad_usage 
    EXPECTED_LABEL=$1

    mode_verify "$EXPECTED_LABEL"
    sqlite3 $DB_FILE "DELETE FROM labels WHERE type = '$LABEL_TYPE' AND labelee = '$LABELEE';"
}

mode_touch()
{
    [ $# = 1 ] || miniade_bad_usage 
    EXPECTED_LABEL=$1

    mode_verify "$EXPECTED_LABEL"
    sqlite3 $DB_FILE "UPDATE labels SET touch_timestamp = $(date +%s) WHERE type = '$LABEL_TYPE' AND labelee = '$LABELEE';"
}

create_tables()
{
    sqlite3 $DB_FILE <<EOF
CREATE TABLE IF NOT EXISTS labels (
    type            CHAR,
    labelee         CHAR,
    label           CHAR,
    touch_timestamp INT,
    PRIMARY KEY (type, labelee),
    -- don't bother checking type as main() does this
    -- don't bother checking label format ias main() does this but do check unique
    UNIQUE (label),
    CHECK (touch_timestamp NOT NULL AND touch_timestamp >= 0)
);
EOF
}

main "$@"