#!/bin/bash

[[ -e ${HOME}/.bashtools/bashtools.sh ]] && . ${HOME}/.bashtools/bashtools.sh
if [[ -n $HAVE_BASHTOOLS ]]; then
    print1="csecho"
    print2="inform"
else
    print1="echo"
    print2="echo"
fi

function usage() {
    echo "usage:  $0 [-n] mode v1 [v2] ... [v3]"
    echo
    echo "   -n:   plaintext mode, no ansi colours"
    echo
    echo "Valid modes:"
    echo "    s = systems in series"
    echo "        v1 = system1 availability%"
    echo "        v2 = system1 availability%"
    echo "        ..."
    echo "    p = systems in parallel"
    echo "        v1 = one system's availability%"
    echo "        v2 = number of systems"
    echo "    i = individual system"
    echo "        v1 = mtbr (mean time between failures)"
    echo "        v2 = mttr (mean time to repair)"
    echo ""
}

function line() {
    local len fmt out
    len=$1
    cmd="printf %0.s- {1..${len}}"
    out=$(bash -c "$cmd")
    echo "$out"
}


if [[ $1 == "-n" ]]; then
    HAVE_BASHTOOLS=""
    shift
fi

mode=$1
shift

if [[ $mode == "s" ]]; then
    if [[ $# -lt 1 ]]; then
        error "usage:  $0 s sys1uptime sys2uptime ... sysXuptime"
        exit 1
    fi
    diagram="[client]\n"
    diagram="${diagram}   |\n"
    diagram="${diagram}[^b${1}%^p uptime]\n"
    eq="(${1}/100)"
    shift
    while [[ $# -ge 1 ]]; do
        diagram="${diagram}   |\n"
        diagram="${diagram}[^b${1}%^p uptime]\n"
        eq="${eq} * (${1}/100)"
        shift
    done
    diagram="${diagram}   |\n"
    diagram="${diagram}[server]\n"
    eq="${eq} * 100"
    answer=$(echo "scale=9; $eq" | bc)
    answershort=$(echo "$answer" | tr -dc '9.')
    nines=$(echo $answershort | tr -d -C 9 | wc -c | tr -d ' ')
    [[ $nines -eq 1 ]] && ess="" || ess="s"
    ninestext="${nines} nine${ess}"


    if [[ -n $HAVE_BASHTOOLS ]]; then
        csecho -e "$WHITE" "^b${UNDERLINE}Architecture^p\n"
        csecho "$GREEN" "${diagram}"
        echo
        csecho -e "$WHITE" "^b${UNDERLINE}Availability^p\n"
        inform "^bEquation:^p     ${eq}"
        inform "^bAvailability:^p ${answershort}% (^b\"$ninestext\"^p)"
        echo
    else
        echo "Architecture"
        echo "------------"
        diagram=$(echo "$diagram" | sed 's/\^.//g')
        echo -e "${diagram}"
        echo
        echo "Availability"
        echo "------------"
        echo "* Equation:     ${eq}"
        echo "* Availability: ${answershort}% (\"$ninestext\")"
        echo
    fi
elif [[ $mode == "p" ]]; then
    if [[ $# -ne 2 ]]; then
        error "usage:  $0 s sysuptime nsystems"
        exit 1
    fi
    sysuptime=${1}
    shift
    nsites=${1}
    shift

    text="[${sysuptime}% uptime]"
    textansi="[^b${sysuptime}%^p uptime]"
    len=${#text}
    biglen=$(( $len * $nsites ))
    biglen=$(echo "$biglen + ($nsites * 3)" | bc)

    len=$((len + 3))

    if [[ $((len % 2)) -eq 0 ]]; then
        s1=$(( $len / 2 ))
        s2=$(( $s1 - 1 ))
        linktext=$(printf "%${s1}s|%${s2}s" " " " ")
    else
        s1=$(( $len / 2 ))
        linktext=$(printf "%${s1}s|%${s1}s" " " " ")
    fi

    diagram="$(line $biglen)"
    diagram="${diagram}\n"
    if [[ $((biglen % 2)) -eq 0 ]]; then
        s1=$(( $biglen / 2 ))
        s2=$(( $s1 - 1 ))
        upd=$(printf "[%${s1}s%${s2}s]" "client")
    else
        s1=$(( $biglen / 2 ))
        upd=$(printf "[%${s1}s%${s1}s]" "client")
    fi
    diagram="${diagram}${upd}"
    diagram="${diagram}\n"
    diagram="${diagram}$(line $biglen)"
    diagram="${diagram}\n"
    # intentially skip element 0
    for ((i=0;i<nsites;i++)); do
        diagram="${diagram}${linktext}"
    done
    diagram="${diagram}\n"

    sysline="$(line ${#text})"
    syslines="${sysline}"
    for ((i=1;i<nsites;i++)); do
        syslines="${syslines}    ${sysline}"
    done
    diagram="${diagram}${syslines}\n"


    diagram="${diagram}${textansi}"
    # intentially skip element 0
    for ((i=1;i<nsites;i++)); do
        diagram="${diagram}    ${textansi}"
    done
    diagram="${diagram}\n"
    diagram="${diagram}${syslines}\n"

    # intentially skip element 0
    for ((i=0;i<nsites;i++)); do
        diagram="${diagram}${linktext}"
    done
    diagram="${diagram}\n"

    if [[ $((biglen % 2)) -eq 0 ]]; then
        s1=$(( $biglen / 2 ))
        s2=$(( $s1 - 1 ))
        upd=$(printf "[%${s1}s%${s2}s]" "server")
    else
        s1=$(( $biglen / 2 ))
        upd=$(printf "[%${s1}s%${s1}s]" "server")
    fi

    diagram="${diagram}$(line $biglen)"
    diagram="${diagram}\n"
    diagram="${diagram}${upd}\n"
    diagram="${diagram}$(line $biglen)"
    diagram="${diagram}\n"


    eq="(1 - (1 - (${sysuptime}/100))^${nsites})*100"
    answer=$(echo "scale=15; $eq" | bc)
    answershort=$(echo "$answer" | tr -dc '9.')
    nines=$(echo $answershort | tr -d -C 9 | wc -c | tr -d ' ')
    [[ $nines -eq 1 ]] && ess="" || ess="s"
    ninestext="${nines} nine${ess}"


    if [[ -n $HAVE_BASHTOOLS ]]; then
        csecho -e "$WHITE" "^b${UNDERLINE}Architecture^p\n"
        csecho "$GREEN" "${diagram}"
        echo
        csecho -e "$WHITE" "^b${UNDERLINE}Availability^p\n"
        inform "^bEquation:^p     ${eq}"
        inform "^bAvailability:^p ${answershort}% (^b\"$ninestext\"^p)"
    else
        echo "Architecture"
        echo "------------"
        diagram=$(echo "$diagram" | sed 's/\^.//g')
        echo -e "${diagram}"
        echo
        echo "Availability"
        echo "------------"
        echo "Equation:     ${eq}"
        echo "Availability: ${answershort}% (\"$ninestext\")"
    fi
    echo
elif [[ $mode == "i" ]]; then
    if [[ $# -ne 2 ]]; then
        error "usage:  $0 i mtbf mttr"
        exit 1
    fi
    mtbf=${1}
    shift
    mttr=${1}
    shift

    eq="${mtbf} / (${mtbf} + ${mttr}) * 100"
    answer=$(echo "scale=15; $eq" | bc)
    answershort=$(echo "$answer" | sed 's/0\+$//')

    if [[ -n $HAVE_BASHTOOLS ]]; then
        csecho -e "$WHITE" "^b${UNDERLINE}Availability^p\n"
        inform "^bMean Time Between Failures:^p  ${mtbf} hours"
        inform "^bMean Time to Repair:^p         ${mttr} hours"
        inform "^bEquation:^p                    ${eq}"
        inform "^bAvailability:^p                $GREEN$BOLD${answershort}%^p"
    else
        echo "Availability"
        echo "------------"
        echo "Mean Time Between Failures:  ${mtbf} hours"
        echo "Mean Time to Repair:         ${mttr} hours"
        echo "Equation:                    ${eq}"
        echo "Availability:                ${answershort}%"
    fi
    echo
else
    if [[ -n $HAVE_BASHTOOLS ]]; then
        error "invalid mode."
    else
        echo "ERROR: invalid mode."
    fi
    usage
    exit 1
fi