#!/bin/bash

# Show RAM usage for containers
# Usage: ./show-ram.sh [compose-file-name]
# Without argument: shows all containers and total server RAM
# With argument: shows containers for specific node

BASEPATH="$(dirname "$0")"
COMPOSE_NAME="$1"

# Function to calculate and print total from container IDs
calc_total() {
    local container_ids="$1"
    local total_mib=$(docker stats --no-stream --format "{{.MemUsage}}" $container_ids | \
        awk -F'/' '{
            val=$1;
            gsub(/[^0-9.]/,"",val);
            if($1 ~ /GiB/) val*=1024;
            sum+=val
        } END {printf "%.0f", sum}')

    if [ "$total_mib" -ge 1024 ] 2>/dev/null; then
        local total_gib=$(echo "scale=2; $total_mib / 1024" | bc)
        echo "${total_gib} GiB"
    else
        echo "${total_mib} MiB"
    fi
}

if [ -z "$COMPOSE_NAME" ]; then
    # No argument: show all containers grouped by compose project
    echo "RAM usage for all nodes:"
    echo "========================================"

    # Get all running containers
    ALL_CONTAINERS=$(docker ps -q 2>/dev/null)

    if [ -z "$ALL_CONTAINERS" ]; then
        echo "No running containers found"
        exit 0
    fi

    # Show stats for all containers, sorted by memory usage (descending)
    docker stats --no-stream --format "table {{.Name}}\t{{.MemUsage}}\t{{.MemPerc}}" $ALL_CONTAINERS | \
        head -1
    docker stats --no-stream --format "{{.Name}}\t{{.MemUsage}}\t{{.MemPerc}}" $ALL_CONTAINERS | \
        sort -t$'\t' -k2 -h -r

    echo "========================================"

    # Calculate total
    echo -n "Total container RAM: "
    calc_total "$ALL_CONTAINERS"

    # Show server total RAM
    total_server_ram=$(free -h | awk '/^Mem:/ {print $2}')
    used_server_ram=$(free -h | awk '/^Mem:/ {print $3}')
    echo "Server RAM: ${used_server_ram} / ${total_server_ram}"
else
    # Specific node
    COMPOSE_FILE="${BASEPATH}/${COMPOSE_NAME}.yml"

    if [ ! -f "$COMPOSE_FILE" ]; then
        echo "Error: Compose file not found: $COMPOSE_FILE"
        exit 1
    fi

    # Get container IDs for this compose project
    CONTAINER_IDS=$(docker compose -f "$COMPOSE_FILE" ps -q 2>/dev/null)

    if [ -z "$CONTAINER_IDS" ]; then
        echo "No running containers found for $COMPOSE_NAME"
        exit 0
    fi

    echo "RAM usage for $COMPOSE_NAME:"
    echo "----------------------------------------"

    # Show stats for each container
    docker stats --no-stream --format "{{.Name}}\t{{.MemUsage}}\t{{.MemPerc}}" $CONTAINER_IDS

    echo "----------------------------------------"
    echo -n "Total: "
    calc_total "$CONTAINER_IDS"
fi