#!/bin/bash

# For those disks like some of my SAS drives where `smartctl
# --nocheck=standby` and `hdparm -C` actually spins up the disk,
# detect whether a disk is spun down with sdparm commands, and don't
# invoke smartctl if it is.  Otherwise, some of our other disks like
# our 16TB SATA drives on Dell Perc controllers give unreliable status to `sdparm
# --command=sense`, but `smartctl --nocheck=standby` does seem to
# reliably detect their spundown state anyway, so we continue to
# supply `--nocheck=standby` to cover this case.

# While we're here, we might as well try transform the mimimal output
# smartctl gives us on SAS drives into something we can parse too, so
# we can at least get temperatures for hddtemp_smartctl's use.  We
# also detect nvme drives and pass off a request to smartctlnvme for
# it to give us smartctl style output on them.

final_arg="${@: -1}"

convert_sas() {
    read_initial=true
    read_data=false
    device_model=
    device_product=
    local exit_code=0
    while read line ; do
        case "$read_initial,$read_data,$line" in
            true,false,*DATA\ SECTION*)
                read_initial=false
                read_data=true
                echo "Device Model: $device_vendor $device_product"
                echo "$line"
                echo "ID# ATTRIBUTE_NAME          FLAG     VALUE WORST THRESH TYPE      UPDATED  WHEN_FAILED RAW_VALUE"
                ;;
            true,false,Vendor:*)
                device_vendor="$( echo "$line" | sed 's/Vendor: *//' )"
                ;;
            true,false,Product:*)
                device_product="$( echo "$line" | sed 's/Product: *//' )"
                ;;
            true*)
                echo "$line"
                ;;
            false,true,SMART\ Health\ Status:*)
                if [[ "$line" == *OK ]] ; then
                    exit_code=0
                else
                    exit_code=8
                fi
#                echo "$line"
                ;;
            false,true,Current\ Drive\ Temperature:*)
                temp="$( echo "$line" | sed 's/.*Temperature: *// ; s/ C$//' )"
                ;;
            false,true,Drive\ Trip\ Temperature:*)
                temp_threshold="$( echo "$line" | sed 's/.*Drive Trip Temperature: *// ; s/ C$//' )"
                hundred_minus_temp="$( printf "%03.f" "$( echo "100 - $temp" | bc -l )" )"
                echo "194 Temperature_Celsius null $hundred_minus_temp $hundred_minus_temp 000 Old_age Always - $temp (Min/Max 0/$temp_threshold)"
                ;;
            false,true,Accumulated\ power\ on\ time,\ hours:minutes:*)
                hours="$( echo "$line" | sed 's/.*hours:minutes // ; s/:.*//' )"
#                minutes="$( echo "$line" | sed 's/.*hours:minutes // ; s/.*://' )"
#                hours="$( echo "scale=2 ; $hours + $minutes/60" | bc -l )"
                echo "9 Power_On_Hours null 100 100 000 Old_age Always - $hours"
                ;;
            false,true,Specified\ cycle\ count\ over\ device\ lifetime:*)
                start_stop_cycles_threshold="$( echo "$line" | sed 's/.*Specified cycle count over device lifetime: *//' )"
                ;;
            false,true,Accumulated\ start-stop\ cycles:*)
                start_stop_cycles="$( echo "$line" | sed 's/.*Accumulated start-stop cycles: *//' )"
                hundred_minus_cycles="$( printf "%03.f" "$( echo "100 - 100*$start_stop_cycles/$start_stop_cycles_threshold" | bc -l )" )"
                echo "12 Power_Cycle_Count null $hundred_minus_cycles $hundred_minus_cycles 000 Pre-fail Always - $start_stop_cycles"
                ;;
            false,true,Specified\ load-unload\ count\ over\ device\ lifetime:*)
                load_unload_cycles_threshold="$( echo "$line" | sed 's/.*Specified load-unload count over device lifetime: *//' )"
                ;;
            false,true,Accumulated\ load-unload\ cycles:*)
                load_unload_cycles="$( echo "$line" | sed 's/.*Accumulated load-unload cycles: *//' )"
                hundred_minus_cycles="$( printf "%03.f" "$( echo "100 - 100*$load_unload_cycles/$load_unload_cycles_threshold" | bc -l )" )"
                echo "193 Load_Cycle_Count null $hundred_minus_cycles $hundred_minus_cycles 000 Pre-fail Always - $load_unload_cycles"
                ;;
            false,true,Elements\ in\ grown\ defect\ list:*)
                defects="$( echo "$line" | sed 's/.*Elements in grown defect list: //' )"
                echo "5 Reallocated_Sector_Ct null 100 100 001 Pre-fail Always - $defects"
                ;;
            false,true,Non-medium\ error\ count:*)
                errors="$( echo "$line" | sed 's/.*Non-medium error count: //' )"
                echo "1 Raw_Read_Error_Rate null 100 100 001 Pre-fail Always - $errors"
                ;;
        esac
    done <<< "$1"

    return $exit_code
}

if [ "1" = --version ] ; then
    # allow munin smart_ check to test for support of --nocheck=standby to ensure it doesnt' then run hdparm
    exec smartctl "$@"
fi

if sdparm --command=sense "$final_arg" 2>/dev/null | grep -e "Standby condition" -e "Idle condition" ; then
    # exit code success rather than code 2 like smartctl by default
    # Could do similar output with hdparm -C, but smartctl
    # --nocheck=standby,0 correctly detects that
    exit
fi

smart_output=$( smartctl --nocheck=idle,0 "$@" )
exit_code=$?

case "$smart_output" in
    *Transport*protocol:*SAS*)
        convert_sas "$smart_output"
        convert_exit=$?

        # FIXME: should work out a proper exit code precedence rule
        if (( $convert_exit > $exit_code )) ; then
            exit $convert_exit
        fi
        exit $exit_code
        ;;
    *NVMe*Version*)
        # to transform smartctl nvme output to more resemble
        # traditional output so existing munin plugins can monitor it
        exec /usr/local/bin/smartctlnvme "$@"
        ;;
    *)
        echo "$smart_output"
        ;;
esac

exit $exit_code
