#!/bin/bash
# mpd announcer for Konversation - dewdude/Jay - dewdude@pickmy.org
# requires mpd and bc
#
# makes direct connection to mpd, polls for information
# spams it as an action to the current channel
# does some sample rate converstion - detects SACD playback

# Kompozer's always passed arguements
SERVER=$1
TARGET=$2
shift
shift
[[ -n "$@" ]] && COMMAND="$@"

# Initialize dbus
_qdbus=${KONVERSATION_DBUS_BIN:-qdbus-qt6}
if ! [ "$(which $_qdbus 2> /dev/null)" ]; then
    _qdbus=qdbus
    if ! [ "$(which $_qdbus 2> /dev/null)" ]; then
        echo "Error: The qdbus (or qdbus-qt6) utility is missing."
        exit 1
    fi
fi

# Script Functions

# Converts decimal seconds to "normal" format
# Arguments: seconds (floating point)
seconds_to_mmss() {
    local total_seconds="$1"

    # Convert to integer (truncate decimal part)
    local int_seconds=$(printf "%.0f" "$total_seconds")

    # Calculate minutes and seconds
    local minutes=$((int_seconds / 60))
    local seconds=$((int_seconds % 60))

    # Format with leading zeros
    printf "%02d:%02d" "$minutes" "$seconds"
}

# Reparses the audio format tag, converts it to khz, and does stuff for DSD/SACD
# Argument: number:number:number (44100:16:2 - usually $audio)
format_audio() {
    local audio_format="$1"

    # Split the format string on colons
    IFS=':' read -r samplerate bitdepth channels <<< "$audio_format"

    # Fix it all to stereo!
    local channel_text="Stereo"
    # DSD is silly, but I still <3 it.
    case $samplerate in
        dsd64)
            local samplerate="2.822MHz"
            local bitdepth="1"
            dsd="DSD64"
            ;;
        dsd128)
            local samplerate="5.644MHz"
            local bitdepth="1"
            dsd="DSD128"
            ;;
        dsd256)
            local samplerate="11.288MHz"
            local bitdepth="1"
            dsd="DSD256"
            ;;
        dsd512)
            local samplerate="22.576MHz"
            local bitdepth="1"
            dsd="DSD512"
            ;;
        *)
            # Converts from Hz to kHz
            local trate="$(echo "scale=1; $samplerate / 1000" | bc)"
            # Drops the trailing zero on sample rates like 192khz
            samplerate="${trate%.0}kHz"
            ;;
    esac

    # Return formatted string - we can't set global variables here so we have to split it out later. Thanks bash!
        echo "${samplerate}/${bitdepth}-bit/${channel_text}|${dsd}"
}


get_extension() {
    local filepath="$1"

    # Get just the filename without the path
    local filename="${filepath##*/}"

    # Extract extension and convert to uppercase
    local extension="${filename##*.}"
    echo "${extension^^}"
}

get_mpd_data() {
# This calls status and currentsong from mpd. writes result as a variable with it's value
# performs some sanitization. TODO: Get you a list of what's used.
    # Send commands to mpd
    printf "command_list_begin\r\nstatus\r\ncurrentsong\r\ncommand_list_end\r\n" >&3

    # Read responses until we get empty line or OK
    while IFS=': ' read -r name value <&3; do
        [[ "$name" == "" ]] && break  # Empty line = end of response
        [[ "$name" == "OK" ]] && break

        # Read each response and convert it in to variable=value
        if [[ -n "$name" && -n "$value" && "$name" =~ ^[a-zA-Z_][a-zA-Z0-9_]*$ ]]; then
            declare -g "$name=$value"  # Use -g for global scope - which works here.
        fi
    done
}

sendtokonversation() {
# Send output to channel and leave
$_qdbus org.kde.konversation /irc say $SERVER "$TARGET" "$spam"

exec 3<&-
exit
}

# We need (or I needed) non-blocking raw TCP. I don't think MPD has a command to close the client connection. I can send Quit or QUIT; and
# it works, but only ineractively. Any attempts to automatically script the commands to nc fail. It's like it doesn't care it saw 5 commands
# before quit...sent in order...or even in command list; you'll get the OK MPD banner and nothing. But this trick right here doesn't care.
# It's just raw TCP directly in shell. All I have to do is remember to read from it.
exec 3<>/dev/tcp/localhost/6600

# Clears the connection string from the buffer
read -r greeting <&3

# Control MPD
# If we're just sending a command, we can just do it here without polling for data.
#
if [[ -n "$COMMAND" ]]; then
    printf "$COMMAND\r\n" >&3
    read -r response <&3
    if [[ $response != "OK" ]]; then
    $_qdbus org.kde.konversation /irc error "mpd: $response"
    fi
    exec 3<&-
    exit
fi

# It's all a giant work around for the fact format_audio can't set globals!
#
# Get the data from MPD
get_mpd_data
case $state in
    stop)
        spam="/me mpd: Not Playing"
        sendtokonversation
        ;;
    pause)
        Artist="[Paused] $Artist"
        ;;
    *)
        ;;
    esac

# Send $audio to format_audio so it can do it's magic. Also is here now due to variable hack.
audio_result=$(format_audio $audio)
# Splits audio_result since we couldn't directly set variables from the function. For some reason. I hate bash.
format_part="${audio_result%|*}"    # Everything before the |
dsd_part="${audio_result#*|}"       # Everything after the |

# Literally determines if it should display DSD, the extension, or DSD/SuperAudioCD
fileext=$(get_extension "$file")
if [[ -z "$dsd_part" ]]; then
    codec_result="$fileext"
elif [[ -n "dsd_part" && "$fileext" == "ISO" ]]; then
    codec_result="$dsd_part/Super Audio CD"
else
    codec_result="$dsd_part"
fi


spam="/me mpd: $Artist - $Title (From: $Album) [$(seconds_to_mmss $elapsed)/$(seconds_to_mmss $duration) | $format_part | $bitrate kbps | $codec_result]"

sendtokonversation