#!/bin/bash

# Function to display usage
usage() {
    echo "Usage: $0 -h host [-l username] [-p password] [-p percentage]"
    echo "  -h host: IP address or hostname of the iDRAC (mandatory)"
    echo "  -l username: Username for IPMI authentication"
    echo "  -p password: Password for IPMI authentication"
    echo "  -p percentage: Percentage value (0-100) to set fan speed (default: 0)"
    exit 1
}

# Check if ipmitool is installed
if ! command -v ipmitool &> /dev/null
then
    echo "Error: ipmitool is not installed. Please install ipmitool to proceed."
    exit 1
fi

# Initialize variables
username=""
password=""
host=""
percentage="0"

# Parse command-line options
while getopts "h:l:p:" opt
do
    case $opt in
        h) host="$OPTARG" ;;
        l) username="$OPTARG" ;;
        p) 
            if [[ "$OPTARG" =~ ^[0-9]+$ && "$OPTARG" -ge 0 && "$OPTARG" -le 100 ]]
            then
                percentage="$OPTARG"
            else
                echo "Error: Percentage value must be an integer between 0 and 100."
                usage
            fi
            ;;
        \?) usage ;;
    esac
done

# Check if mandatory -h option is provided
if [[ -z ${host} ]]
then
    echo "Error: -h (host) option is mandatory."
    usage
fi

# Prompt for username if not provided via getopts
if [[ -z ${username} ]]
then
    echo -n "Enter username: "
    read username
fi

# Prompt for password if not provided via getopts
if [[ -z ${password} ]]
then
    echo -n "Enter password: "
    read -s password
fi

# Disable automatic fan speed control
ipmitool -I lanplus -H "${host}" -U "${username}" -P "${password}" raw 0x30 0x30 0x01 0x00

# Set fan speed based on percentage
if [[ -n ${percentage} ]]
then
    value=$(printf "%x\n" $((percentage * 64 / 100)))
    ipmitool -I lanplus -H "${host}" -U "${username}" -P "${password}" raw 0x30 0x30 0x02 0xff 0x${value}
fi