#!/usr/bin/env bash

# Usage: ./frequented.sh [number=5]
# Lists your top `number` most frequented channels
# Single threaded, still does 1.22 milliseconds per channel
# (on a 5600X with 2289 channels and 385952 messages)

# set this to your id to not print your id in dms/group chats
SELF_ID="${SELF_ID:-276363003270791168}"

n=$((${1:-5}))

repeat() {
    local n=${2?}
    for ((i=0; i<n; i++)); do echo "${1?}"; done
}

# shellcheck disable=SC2207
counts=($(repeat '0' $n))
# shellcheck disable=SC2207
channels=($(repeat 'none' $n))

# insert $1 and $2 into index $3 and drop last element
insert() {
    local value1=${1?}
    local value2=${2?}
    local idx=${3:-0}

    counts=("${counts[@]:0:$idx}" "$value1" "${counts[@]:$idx:$((n - idx - 1))}")
    channels=("${channels[@]:0:$idx}" "$value2" "${channels[@]:$idx:$((n - idx - 1))}")
}

total_messages=0
total_channels=0

word_count() {
    local total=0
    while read -r; do
        total=$((total + 1))
    done
    echo $total
}

time for dir in c*; do
    channel=${dir#c}
    count=$(("$(word_count < "$dir"/messages.csv)" - 1))
    total_messages=$((total_messages + count))
    total_channels=$((total_channels + 1))
    for ((i=0; i<n; i++)); do
        if ((count > ${counts[$i]})); then
            insert $count "$channel" $i
            break
        fi
    done
done

echo "total channels: $total_channels"
echo "total messages: $total_messages"
echo "most frequented $n channels:"
for ((i=0; i<n; i++)); do
    # 1 and 3 are DM and GROUP_DM respectively
    # https://discord.com/developers/docs/resources/channel#channel-object-channel-types
    # if you want to understand the following `jq` filter,
    # start reading here: https://jqlang.github.io/jq/manual/#basic-filters
    channel_text=$(jq 'if .type == 1 // .type == 3 then
	    .id + " (" + if (.recipients | length) > 2 then
	        "GC with "
	    else
	        "DM with "
	    end + (.recipients | map(select(. != "'"$SELF_ID"'")) | join(", ")) + ")"
	else
	    if has("name") then
	        "#" + .name + " (" + .guild.name + ")"
	    else
	        .id + " (unknown guild)"
	    end
	end' c"${channels[$i]}"/channel.json)
    echo "$((i + 1)). messages: ${counts[$i]}, channel: $channel_text"
done