#!/bin/bash

# Battery Status Monitor
# Displays detailed battery information and power consumption

set -euo pipefail

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
CYAN='\033[0;36m'
NC='\033[0m' # No Color

# Function to print header
print_header() {
    echo -e "${BLUE}=================================================${NC}"
    echo -e "${BLUE}          Battery Status Monitor${NC}"
    echo -e "${BLUE}=================================================${NC}"
    echo
}

# Function to get battery information
get_battery_info() {
    local bat_path="/sys/class/power_supply"
    local ac_path="/sys/class/power_supply/A[CD]*"
    
    echo -e "${CYAN}Battery Information:${NC}"
    echo "----------------------------------------"
    
    # Find all batteries
    for battery in "$bat_path"/BAT*; do
        if [[ -d "$battery" ]]; then
            local bat_name=$(basename "$battery")
            local capacity=$(cat "$battery/capacity" 2>/dev/null || echo "N/A")
            local status=$(cat "$battery/status" 2>/dev/null || echo "N/A")
            local voltage=$(cat "$battery/voltage_now" 2>/dev/null || echo "0")
            local current=$(cat "$battery/current_now" 2>/dev/null || echo "0")
            local energy_full=$(cat "$battery/energy_full" 2>/dev/null || echo "0")
            local energy_now=$(cat "$battery/energy_now" 2>/dev/null || echo "0")
            local power_now=$(cat "$battery/power_now" 2>/dev/null || echo "0")
            
            # Convert values to human readable format
            voltage_v=$(echo "scale=2; $voltage / 1000000" | bc -l 2>/dev/null || echo "0")
            current_a=$(echo "scale=2; $current / 1000000" | bc -l 2>/dev/null || echo "0")
            energy_full_wh=$(echo "scale=2; $energy_full / 1000000" | bc -l 2>/dev/null || echo "0")
            energy_now_wh=$(echo "scale=2; $energy_now / 1000000" | bc -l 2>/dev/null || echo "0")
            power_w=$(echo "scale=2; $power_now / 1000000" | bc -l 2>/dev/null || echo "0")
            
            # Color code based on battery level
            if (( $(echo "$capacity >= 80" | bc -l) )); then
                color=$GREEN
            elif (( $(echo "$capacity >= 50" | bc -l) )); then
                color=$YELLOW
            else
                color=$RED
            fi
            
            echo -e "${BLUE}$bat_name:${NC}"
            echo -e "  Capacity:     ${color}${capacity}%${NC}"
            echo -e "  Status:       $status"
            echo -e "  Voltage:      ${voltage_v}V"
            echo -e "  Current:      ${current_a}A"
            echo -e "  Power:        ${power_w}W"
            echo -e "  Energy:       ${energy_now_wh}Wh / ${energy_full_wh}Wh"
            
            # Calculate remaining time
            if [[ "$status" == "Discharging" ]] && (( $(echo "$power_w > 0" | bc -l) )); then
                remaining_hours=$(echo "scale=2; $energy_now_wh / $power_w" | bc -l)
                remaining_minutes=$(echo "scale=0; $remaining_hours * 60" | bc -l)
                hours=$(echo "scale=0; $remaining_minutes / 60" | bc -l)
                minutes=$(echo "scale=0; $remaining_minutes % 60" | bc -l)
                echo -e "  Time left:    ${hours}h ${minutes}m"
            elif [[ "$status" == "Charging" ]] && (( $(echo "$power_w > 0" | bc -l) )); then
                charge_needed=$(echo "scale=2; $energy_full_wh - $energy_now_wh" | bc -l)
                charge_time=$(echo "scale=2; $charge_needed / $power_w" | bc -l)
                charge_minutes=$(echo "scale=0; $charge_time * 60" | bc -l)
                charge_hours=$(echo "scale=0; $charge_minutes / 60" | bc -l)
                charge_mins=$(echo "scale=0; $charge_minutes % 60" | bc -l)
                echo -e "  Time to full: ${charge_hours}h ${charge_mins}m"
            fi
            echo
        fi
    done
    
    # Check AC adapter status
    for ac in $ac_path; do
        if [[ -d "$ac" ]] 2>/dev/null; then
            local ac_name=$(basename "$ac")
            local ac_online=$(cat "$ac/online" 2>/dev/null || echo "0")
            if [[ "$ac_online" == "1" ]]; then
                echo -e "AC Adapter:       ${GREEN}Connected${NC}"
            else
                echo -e "AC Adapter:       ${RED}Disconnected${NC}"
            fi
            break
        fi
    done
    echo
}

# Function to show TLP status
show_tlp_status() {
    if command -v tlp-stat &> /dev/null; then
        echo -e "${CYAN}TLP Status:${NC}"
        echo "----------------------------------------"
        tlp-stat -s 2>/dev/null | head -10
        echo
    fi
}

# Function to show power consumption
show_power_consumption() {
    echo -e "${CYAN}Power Consumption:${NC}"
    echo "----------------------------------------"
    
    # Try to get power consumption from various sources
    local power_consumption=""
    
    # Method 1: From battery power_now
    for battery in /sys/class/power_supply/BAT*; do
        if [[ -d "$battery" ]]; then
            local power_now=$(cat "$battery/power_now" 2>/dev/null || echo "0")
            if [[ "$power_now" != "0" ]]; then
                power_w=$(echo "scale=2; $power_now / 1000000" | bc -l)
                power_consumption="$power_w"
                break
            fi
        fi
    done
    
    if [[ -n "$power_consumption" ]]; then
        echo -e "Current draw:     ${power_consumption}W"
    else
        echo "Power consumption data not available"
    fi
    
    # CPU frequency information
    if [[ -f /proc/cpuinfo ]]; then
        local cpu_freq=$(cat /proc/cpuinfo | grep "cpu MHz" | head -1 | awk '{print $4}')
        if [[ -n "$cpu_freq" ]]; then
            echo -e "CPU frequency:    ${cpu_freq} MHz"
        fi
    fi
    
    # Load average
    local load_avg=$(cat /proc/loadavg | awk '{print $1, $2, $3}')
    echo -e "Load average:     $load_avg"
    
    # Temperature (if available)
    if command -v sensors &> /dev/null; then
        local temp=$(sensors | grep "Core 0" | awk '{print $3}' | head -1)
        if [[ -n "$temp" ]]; then
            echo -e "CPU temperature:  $temp"
        fi
    fi
    
    echo
}

# Function to show system uptime and power efficiency
show_efficiency() {
    echo -e "${CYAN}System Efficiency:${NC}"
    echo "----------------------------------------"
    
    # Uptime
    local uptime_info=$(uptime -p)
    echo -e "Uptime:           $uptime_info"
    
    # Memory usage
    local mem_info=$(free -h | grep "Mem:" | awk '{print "Used: " $3 " / " $2}')
    echo -e "Memory:           $mem_info"
    
    # Disk activity
    if command -v iostat &> /dev/null; then
        local disk_usage=$(iostat -d 1 2 | tail -n +4 | head -1 | awk '{print $4 + $5}')
        echo -e "Disk I/O:         ${disk_usage} KB/s"
    fi
    
    echo
}

# Function to provide power saving tips
show_tips() {
    echo -e "${CYAN}Power Saving Tips:${NC}"
    echo "----------------------------------------"
    echo "• Lower screen brightness"
    echo "• Close unused applications"
    echo "• Disable unused wireless devices"
    echo "• Use power saving mode"
    echo "• Enable TLP and PowerTOP optimizations"
    echo "• Consider using an SSD instead of HDD"
    echo
}

# Main function
main() {
    # Check if bc is available for calculations
    if ! command -v bc &> /dev/null; then
        echo "Installing bc for calculations..."
        sudo apt update && sudo apt install -y bc
    fi
    
    # Clear screen and show header
    clear
    print_header
    
    # Show all information
    get_battery_info
    show_tlp_status
    show_power_consumption
    show_efficiency
    show_tips
    
    echo -e "${BLUE}Last updated: $(date)${NC}"
}

# Watch mode - refresh every 5 seconds
if [[ "${1:-}" == "--watch" ]]; then
    while true; do
        main
        sleep 5
    done
else
    main
fi