#! /bin/bash

set -e

BIN=$HOME/bin
STATUS_DIR=$HOME/var/run/status
STATUS_FILE__WIFI=$STATUS_DIR/wifi
STATUS_FILE__ENERGY_NOTIFIED_BELLOW_HALF=$STATUS_DIR/notified_energy_bellow_half
while getopts ":b:d:s:i:w:" opt
do
    case "$opt" in
        b)
            SCREEN_BRIGHTNESS_DEVICE_NAME="$OPTARG"
            ;;
        d)
            DISK_IO_DEVICE="$OPTARG"
            ;;
        s)
            DISK_SPACE_DEVICE="$OPTARG"
            ;;
        i)
            PREFIXES_OF_INTERFACES_TO_SHOW="$OPTARG"
            ;;
        w)
            WEATHER_STATION_ID="$OPTARG"
            ;;
        \?)
            echo "Unknown option: $OPTARG" >&2
            exit 1
            ;;
        :)
            echo "Missing argument for option: $OPTARG" >&2
            exit 1
            ;;
    esac
done
if [ "$SCREEN_BRIGHTNESS_DEVICE_NAME" == '' ]; then echo 'Missing -b' >&2; exit 1; fi
if [ "$DISK_IO_DEVICE" == '' ];                then echo 'Missing -d' >&2; exit 1; fi
if [ "$DISK_SPACE_DEVICE" == '' ];             then echo 'Missing -s' >&2; exit 1; fi
if [ "$WEATHER_STATION_ID" == '' ];            then echo 'Missing -w' >&2; exit 1; fi
SCREEN_BRIGHTNESS_DEVICE_PATH="/sys/class/backlight/$SCREEN_BRIGHTNESS_DEVICE_NAME"


load=$(awk '{printf("%4.2f", $1)}' /proc/loadavg)

fan=$(awk '/^speed:/ {printf "%4d", $2}' /proc/acpi/ibm/fan)

#cpu=$($BIN/khatus_cpu_usage_from_proc_since_last_check)

memory=$(
    free \
    | awk '
        function round(n) {return int(n + 0.5)}

        $1 == "Mem:" {
            total=$2;
            used=$3;
            cache=$6;
            prev_file = ENVIRON["HOME"] "/var/run/status/memory_used_percentage";
            curr = round(used / total * 100);
            getline prev < prev_file;
            print curr > prev_file;
            if (curr > prev) {
                direction = ">";
            } else if (curr < prev) {
                direction = "<";
            } else {
                direction = "=";
            }
            printf("%s%d%%", direction, curr);
        }')

temp=$(awk 'NR == 1 {print $1 / 1000}' /sys/class/thermal/thermal_zone0/temp)

disk_io=$(
    awk '
        {
            bytes_per_sector = 512
            bytes_per_unit   = 1024 * 1024

            curr_sectors_read  = $3
            curr_sectors_write = $7

            prev_file_prefix        = ENVIRON["HOME"] "/var/run/status/disk_io"
            prev_sectors_read_file  = prev_file_prefix "_sectors_read"
            prev_sectors_write_file = prev_file_prefix "_sectors_write"

            getline prev_sectors_read  < prev_sectors_read_file
            getline prev_sectors_write < prev_sectors_write_file

            diff_read_sectors  = (curr_sectors_read  - prev_sectors_read)
            diff_write_sectors = (curr_sectors_write - prev_sectors_write)

            diff_read_bytes  = diff_read_sectors  * bytes_per_sector
            diff_write_bytes = diff_write_sectors * bytes_per_sector

            diff_read  = diff_read_bytes  / bytes_per_unit
            diff_write = diff_write_bytes / bytes_per_unit

            print curr_sectors_read  > prev_sectors_read_file
            print curr_sectors_write > prev_sectors_write_file

            printf("%0.3f▲ %0.3f▼\n", diff_write, diff_read);

        }
        ' "/sys/block/$DISK_IO_DEVICE/stat"
)

disk=$(
    df \
    | awk \
        -v disk_io="$disk_io" \
        -v device="$DISK_SPACE_DEVICE" \
        '
        function round(n) {return int(n + 0.5)}

        $1 == device {
            curr_perc = $5; sub("%$", "", curr_perc);
            prev_perc_file = ENVIRON["HOME"] "/var/run/status/disk_space_used";
            getline prev_perc   < prev_perc_file;
            print curr_perc > prev_perc_file;
            if (curr_perc > prev_perc) {
                direction = ">";
            } else if (curr_perc < prev_perc) {
                direction = "<";
            } else {
                direction = "=";
            }
            printf("%s[%d%% %s]", direction, curr_perc, disk_io);
        }')

# TODO: Wi-Fi status file should be a file per-wifi-device
network=$(
    ip -s addr \
    | awk \
        -v wifi_conn="$(cat $STATUS_FILE__WIFI)" \
        -v prefixes_of_interfaces_to_show="$PREFIXES_OF_INTERFACES_TO_SHOW" \
        '
        BEGIN {
            bytes_per_unit = 1024 * 1024
        }

        /^[0-9]+:/ {
            sub(":$", "", $1)
            sub(":$", "", $2)
            sequence = $1
            interface = $2
            interfaces[sequence] = interface
        }

        /^ +inet [0-9]/ {
            sub("/[0-9]+", "", $2)
            addr = $2
            addrs[interface] = addr
        }

        /^ +RX: / {transfer_direction = "r"}
        /^ +TX: / {transfer_direction = "w"}

        /^ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ +[0-9]+ *$/ {
            io[interface, transfer_direction] = $1;
        }

        END {
            for (seq=1; seq<=sequence; seq++) {
                interface = interfaces[seq]
                label = substr(interface, 1, 1)
                if (addrs[interface]) {
                    curr_read  = io[interface, "r"]
                    curr_write = io[interface, "w"]

                    prefix = ENVIRON["HOME"] "/var/run/status/io_net_" interface
                    prev_read_file  = prefix "_read"
                    prev_write_file = prefix "_write"

                    getline prev_read < prev_read_file
                    getline prev_write < prev_write_file

                    diff_read    = (curr_read  - prev_read ) / bytes_per_unit
                    diff_written = (curr_write - prev_write) / bytes_per_unit

                    print curr_read  > prev_read_file
                    print curr_write > prev_write_file

                    io_stat = sprintf("%0.3f▲ %0.3f▼", diff_written, diff_read)
                    if (interface ~ "^w") {
                        label = label ":" wifi_conn
                    }
                } else {
                    io_stat = "--"
                }
                number_of_interfaces_to_show = \
                    split(\
                        prefixes_of_interfaces_to_show,\
                        array_of_prefixes_of_interfaces_to_show,\
                        " +"\
                    )
                for (n = 1; n <= number_of_interfaces_to_show; n++) {
                    prefix = array_of_prefixes_of_interfaces_to_show[n]
                    if (interface ~ ("^" prefix)) {
                        if (++count_printed > 1) {
                            sep = "  "
                        } else {
                            sep = ""
                        }
                        printf("%s%s:%s", sep, label, io_stat)
                    }
                }
            }
        }'
)

energy=$(
    upower -e \
    | grep battery \
    | xargs upower -i \
    | awk '
        /^ +percentage: +/ {percentage=$2}
        /^ +state: +/      {state=$2}
        END {
            if (state == "discharging") {
                direction_of_change = "<"
            } else if (state == "charging") {
                direction_of_change = ">"
            } else {
                direction_of_change = "="
            };
            printf("%s%s", direction_of_change, percentage)
        }')

datetime=$(date +'%a %b %d %H:%M:%S')
#datetime=$(
#    date +'%a %u %b %d %H:%M:%S' \
#    | awk '
#        {
#            wday_name = $1
#            wday_seq  = $2
#            month     = $3
#            mday      = $4
#            time      = $5
#
#            week = ""
#            for (i=1; i<=7; i++) {
#                if (i == 6 || i == 4) {
#                    sep = " "
#                } else {
#                    sep = ""
#                }
#
#                if (i == wday_seq) {
#                    #symbol = substr(wday_name, 1, 1)
#                    symbol = "/"
#                } else if (i < wday_seq){
#                    symbol = "X"
#                } else {
#                    symbol = "_"
#                }
#                week = week sep symbol
#            }
#
#            print "["week"]", month, mday, time;
#        }
#    '
#)

#volume_amixer=$(
#    amixer get Master \
#    | tail -1 \
#    | awk '
#        {
#            level = $4;
#            sub("^\\[", "", level);
#            sub("\\]$", "", level);
#            print level;
#        }' \
#    )

#volume_amixer=$(
#    amixer get Master \
#    | tail -n 1 \
#    | awk '{print $4}' \
#    | tr -d '[]'
#)

volume_pactl=$(
    pactl list sinks \
    | awk '
        /^\tMute:/ {
            printf("%s,", $0);
        }
        /^\tVolume:/ {
            for (i=2; i<=NF; i++) printf(" %s", $i);
        }' \
    | awk -v RS=',' '
        /^[ \t]*Mute:/        {mute  = $2}
        /^[ \t]*front-left:/  {left  = $4}
        /^[ \t]*front-right:/ {right = $4}
        END {
            if (mute == "yes") {
                printf("x")
            } else {
                printf("%s %s", left, right)
            }
        }
        '
)

volume="($volume_pactl)"

screen_brightness=$(
    echo -n $((
          $(cat $SCREEN_BRIGHTNESS_DEVICE_PATH/brightness)
        / $(cat $SCREEN_BRIGHTNESS_DEVICE_PATH/max_brightness)
        * 100
    ))
)

#bluetooth_status=$(
#    grep '^status:' /proc/acpi/ibm/bluetooth \
#    | awk '
#        $2 == "disabled" {printf "off"}
#        $2 == "enabled"  {printf "on"}
#        '
#)

bluetooth_power=$(
    echo -e 'show \n quit' \
    | bluetoothctl \
    | awk '
        /^Controller / {
            controller = $2;
            controllers[++ctrl_count] = controller;
        }
        /^\t[A-Z][A-Za-z]+:/ {
            key = $1;
            sub(":$", "", key);
            val = $2;
            for (i=3; i<=NF; i++) {
                val = val " " $i};
                data[controller, key] = val;
        }
        END {
            # Using the 1st seen controller. Should we select specific instead?
            power_status = data[controllers[1], "Powered"];
            if (ctrl_count > 0) {
                if (power_status == "no") {
                    power_status = "off"
                } else if (power_status == "yes") {
                    power_status = "on"
                } else {
                    printf("Unexpected bluetooth power status: %s\n", power_status)\
                        > "/dev/stderr";
                    power_status = "ERROR"
                }
            } else {
                power_status = "off"  # TODO: Perhaps use differentiated marker?
            }
            printf("%s", power_status);
        }'
)

#touchpad_status=$(
#    xinput list-props 12 \
#    | awk '
#        /^\tDevice Enabled \([0-9]+\):/ {
#            status = $4;
#            printf("%s", status);
#        }'
#)

#color_off='\033[0m'
#color_on_bg_gray='\033[m\033[40m'

energy_direction=$(echo "$energy" | cut -b 1)
energy_percentage=$(echo "$energy" | tr -d '<>=%')
if [[ "$energy_direction" = '<' ]]
then
    if [[ $energy_percentage -le 5 ]]
    then
        DISPLAY=:0.0 notify-send \
            -u critical \
            "Energy CRITICALLY low: $energy" \
            'CHARGE NOW!!! GO GO GO!!!'
    elif [[ $energy_percentage -le 10 ]]
    then
        DISPLAY=:0.0 notify-send \
            -u critical \
            "Energy VERY low: $energy" \
            'Plug it in ASAP.'
    elif [[ $energy_percentage -le 15 ]]
    then
        DISPLAY=:0.0 notify-send \
            -u critical \
            "Energy low: $energy" \
            'Get the charger.'
    elif [[ $energy_percentage -le 50 ]]
    then
        if [[ ! -a "$STATUS_FILE__ENERGY_NOTIFIED_BELLOW_HALF" ]]
        then
            DISPLAY=:0.0 notify-send \
                -u normal \
                "Energy bellow half: $energy" \
                'Where is the charger?'
            touch "$STATUS_FILE__ENERGY_NOTIFIED_BELLOW_HALF"
        fi
    fi
else
    rm -f "$STATUS_FILE__ENERGY_NOTIFIED_BELLOW_HALF"
fi

weather=$(
    awk \
        'NR == 1 {printf("%s°F", $1)}' \
        "$HOME/var/run/metar-${WEATHER_STATION_ID}-decoded-temp-fahrenheit"
)

#signal_last_msg_age=$(
#    ls -lt --time-style=+%s $HOME/var/lib/signal/latest_message.json \
#    | awk -v now_seconds=$(date +%s) \
#    '{
#        mtime_seconds = $6;
#        seconds = now_seconds - mtime_seconds;
#        minutes = seconds / 60;
#        hours   = minutes / 60;
#        days    = hours / 24;
#        weeks   = days / 7;
#        months  = days / 30;
#        #fmt = "%.1f";
#        fmt = "%d";
#        printf(fmt " s\n", seconds);
#        printf(fmt " m\n", minutes);
#        printf(fmt " h\n", hours);
#        printf(fmt " d\n", days);
#        printf(fmt " w\n", weeks);
#        printf(fmt " mo\n", months);
#    }' \
#    | awk '$1 >= 1' \
#    | sort -n -k 1 \
#    | head -1 \
#    | tr -d ' '
#)

mpd_currentsong=$(
    echo 'currentsong' \
    | nc 127.0.0.1 6600 \
    | awk -v max_chars=10 '
        /^OK/ {
            next
        }

        {
            key = $1
            val = $2
            for (i=3; i<=NF; i++) {val = val " " $i}
            data[key] = val
        }

        END {
            name  = data["Name:"]
            title = data["Title:"]
            file  = data["file:"]

            if (name) {
                out = name
            } else if (title) {
                out = title
            } else if (file) {
                last = split(file, parts, "/")
                out = parts[last]
            } else {
                out = ""
            }

            printf("%s", substr(out, 1, max_chars))
        }
        '
)

mpd_state=$(
    echo 'status' \
    | nc 127.0.0.1 6600 \
    | awk \
        -v current_song="$mpd_currentsong" \
        '
        {
            status[$1] = $2
        }

        /^time: +[0-9]+:[0-9]+$/ {
            split($2, time, ":")
            seconds_current = time[1]
            seconds_total   = time[2]

            hours = int(seconds_current / 60 / 60);
            secs_beyond_hours = seconds_current - (hours * 60 * 60);
            mins = int(secs_beyond_hours / 60);
            secs = secs_beyond_hours - (mins * 60);
            if (hours > 0) {
                current_time = sprintf("%d:%.2d:%.2d", hours, mins, secs)
            } else {
                current_time = sprintf("%.2d:%.2d", mins, secs)
            }

            if (seconds_total > 0) {
                time_percentage = (seconds_current / seconds_total) * 100
                current_percentage = sprintf("%d%%", time_percentage)
            } else {
                current_percentage = "~"
            }
        }

        function print_known_state(symbol) {
            printf(\
                "%s %s %s %s",
                symbol, current_time, current_percentage, current_song \
            )
        }

        function print_unknown_state(symbol) {
            printf("%s", symbol)
        }

        END {
            state = status["state:"]

            if (state == "play") {
                print_known_state("▶")
            } else if (state == "pause") {
                print_known_state("❚❚")
            } else if (state == "stop") {
                print_known_state("⬛")
            } else {
                print_unknown_state("--")
            }
        }
        '
)

#graphics_card=$(
    #nvidia-smi \
        #--format=csv,noheader,nounits \
        #--query-gpu=memory.total,memory.used,temperature.gpu \
    #| awk -F ',' '
        #{
            #mem_total = $1;
            #mem_used  = $2;
            #temp      = $3;
            #mem_used_percent = (100 * mem_used) / mem_total;
            #printf("[%d%% %dC]", mem_used_percent, temp);
        #}
        #'
#)

echo \
"\
 E$energy\
 \
 M$memory\
 \
 C=[$load ${temp}°C ${fan}rpm]\
 \
 D$disk\
 \
 N:[$network]\
 \
 B:$bluetooth_power\
 \
 *$screen_brightness%\
 \
 $volume\
 \
 [$mpd_state]\
 \
 $weather\
 \
 $datetime \
"