#!/usr/bin/env bash

get_tmux_option() {
    local option_value
    option_value=$(tmux show-option -gqv "$1")
    echo "${option_value:-$2}"
}

######
# Configurable options
#
# Usage examle:
# set -g @aw-watcher-tmux-host 'my.aw-server.test'
POLL_INTERVAL=$(get_tmux_option "@aw-watcher-tmux-poll-interval" 10) # seconds
HOST=$(get_tmux_option "@aw-watcher-tmux-host" "localhost")
PORT=$(get_tmux_option "@aw-watcher-tmux-port" "5600")
PULSETIME=$(get_tmux_option "@aw-watcher-tmux-pulsetime" "120.0")

BUCKET_ID="aw-watcher-tmux"
API_URL="http://$HOST:$PORT/api"

######
# Related documentation:
#  * https://github.com/tmux/tmux/wiki/Formats
#  * https://github.com/tmux/tmux/wiki/Advanced-Use#user-content-getting-information
#

### FUNCTIONS

DEBUG=0
TMP_FILE=$(mktemp)
echo "$TMP_FILE"

init_bucket() {
    HTTP_CODE=$(curl -X GET "${API_URL}/0/buckets/$BUCKET_ID" -H "accept: application/json" -s -o /dev/null -w "%{http_code}")
    if ((HTTP_CODE == 404)); then # not found
        JSON="{\"client\":\"$BUCKET_ID\",\"type\":\"tmux.sessions\",\"hostname\":\"$(uname -n)\"}"
        HTTP_CODE=$(curl -X POST "${API_URL}/0/buckets/$BUCKET_ID" -H "accept: application/json" -H "Content-Type: application/json" -d "$JSON" -s -o /dev/null -w "%{http_code}")
        if ((HTTP_CODE != 200)); then
            echo "ERROR creating bucket"
            exit 1
        fi
    fi
}

log_to_bucket() {
    sess=$1
    DATA=$(tmux display -t "$sess" -p "{\"title\":\"#{session_name}\",\"session_name\":\"#{session_name}\",\"window_name\":\"#{window_name}\",\"pane_title\":\"#{pane_title}\",\"pane_current_command\":\"#{pane_current_command}\",\"pane_current_path\":\"#{pane_current_path}\"}")
    PAYLOAD="{\"timestamp\":\"$(date -Is)\",\"duration\":0,\"data\":$DATA}"
    echo "$PAYLOAD"
    HTTP_CODE=$(curl -X POST "${API_URL}/0/buckets/$BUCKET_ID/heartbeat?pulsetime=$PULSETIME" -H "accept: application/json" -H "Content-Type: application/json" -d "$PAYLOAD" -s -o "$TMP_FILE" -w "%{http_code}")
    if ((HTTP_CODE != 200)); then
        echo "Request failed"
        cat "$TMP_FILE"
    fi

    if [[ "$DEBUG" -eq "1" ]]; then
        cat "$TMP_FILE"
    fi
}

### MAIN POLL LOOP

declare -A act_last
declare -A act_current

init_bucket

while true; do
    #clear
    sessions=$(tmux list-sessions | awk '{print $1}')
    if ! tmux list-sessions &>/dev/null; then
        echo "tmux list-sessions ERROR: $?"
    fi
    LAST_IFS=$IFS
    IFS=$'\n'

    readarray -t session_list <<<"$sessions"
    for sess in "${session_list[@]}"; do
        act_time=$(tmux display -t "$sess" -p '#{session_activity}')
        if [[ ! -v "act_last[$sess]" ]]; then
            act_last[$sess]='0'
        fi
        if ((act_time > ${act_last[$sess]})); then
            # echo "###> "$sess' '$(date -Iseconds)'    '$act_time' '$act_last[$sess] ##  >> tmux-sess-act.log
            log_to_bucket "$sess"
        fi
        act_current[$sess]=$act_time
    done
    IFS=$LAST_IFS
    for sess in "${!act_current[@]}"; do
        act_last[$sess]=${act_current[$sess]}
    done

    sleep "$POLL_INTERVAL"
done