#!/bin/bash

# Battery Life Optimizer - TLP and PowerTOP Installation Script
# For Debian/Ubuntu-based Linux distributions

set -euo pipefail

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

# Logging function
log() {
    echo -e "${BLUE}[$(date +'%Y-%m-%d %H:%M:%S')]${NC} $1"
}

success() {
    echo -e "${GREEN}[SUCCESS]${NC} $1"
}

warning() {
    echo -e "${YELLOW}[WARNING]${NC} $1"
}

error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# Check if running as root
check_root() {
    if [[ $EUID -eq 0 ]]; then
        error "This script should not be run as root!"
        error "It will use sudo when necessary."
        exit 1
    fi
}

# Check if system is supported
check_system() {
    if [[ ! -f /etc/debian_version ]] && [[ ! -f /etc/ubuntu_version ]]; then
        warning "This script is optimized for Debian/Ubuntu systems."
        read -p "Continue anyway? (y/N): " -n 1 -r
        echo
        if [[ ! $REPLY =~ ^[Yy]$ ]]; then
            exit 1
        fi
    fi
}

# Update package lists
update_packages() {
    log "Updating package lists..."
    sudo apt update
    success "Package lists updated"
}

# Install TLP
install_tlp() {
    log "Installing TLP (Advanced Power Management)..."
    
    # Check if TLP is already installed
    if command -v tlp &> /dev/null; then
        warning "TLP is already installed"
        return 0
    fi
    
    # Install TLP and additional packages
    sudo apt install -y tlp tlp-rdw
    
    # For ThinkPads, install additional tools
    if dmidecode -s system-product-name | grep -qi "thinkpad"; then
        log "ThinkPad detected, installing additional tools..."
        sudo apt install -y tp-smapi-dkms acpi-call-dkms
    fi
    
    # Enable and start TLP service
    sudo systemctl enable tlp.service
    sudo systemctl start tlp.service
    
    success "TLP installed and configured"
}

# Install PowerTOP
install_powertop() {
    log "Installing PowerTOP..."
    
    # Check if PowerTOP is already installed
    if command -v powertop &> /dev/null; then
        warning "PowerTOP is already installed"
        return 0
    fi
    
    sudo apt install -y powertop
    
    success "PowerTOP installed"
}

# Setup PowerTOP service for automatic tuning
setup_powertop_service() {
    log "Setting up PowerTOP auto-tune service..."
    
    # Create systemd service file for PowerTOP
    sudo tee /etc/systemd/system/powertop.service > /dev/null <<EOF
[Unit]
Description=PowerTOP auto tune
After=multi-user.target

[Service]
Type=oneshot
ExecStart=/usr/sbin/powertop --auto-tune
RemainAfterExit=true

[Install]
WantedBy=multi-user.target
EOF
    
    # Enable the service
    sudo systemctl daemon-reload
    sudo systemctl enable powertop.service
    
    success "PowerTOP auto-tune service configured"
}

# Backup existing TLP configuration
backup_tlp_config() {
    local tlp_config="/etc/tlp.conf"
    local backup_file="/etc/tlp.conf.backup.$(date +%Y%m%d_%H%M%S)"
    
    if [[ -f "$tlp_config" ]]; then
        log "Backing up existing TLP configuration..."
        sudo cp "$tlp_config" "$backup_file"
        success "TLP configuration backed up to $backup_file"
    fi
}

# Apply optimized TLP configuration
apply_tlp_config() {
    log "Applying optimized TLP configuration..."
    
    local config_file="../config/tlp.conf"
    if [[ -f "$config_file" ]]; then
        sudo cp "$config_file" /etc/tlp.conf
        success "TLP configuration applied"
    else
        warning "Optimized TLP config file not found. Using default configuration."
    fi
}

# Install additional power management tools
install_additional_tools() {
    log "Installing additional power management tools..."
    
    sudo apt install -y \
        laptop-mode-tools \
        thermald \
        cpufrequtils \
        smartmontools \
        ethtool
    
    success "Additional tools installed"
}

# Main installation function
main() {
    log "Starting Battery Life Optimizer installation..."
    
    check_root
    check_system
    
    update_packages
    install_tlp
    install_powertop
    setup_powertop_service
    install_additional_tools
    
    backup_tlp_config
    apply_tlp_config
    
    # Start TLP
    log "Starting TLP service..."
    sudo tlp start
    
    success "Installation completed successfully!"
    echo
    log "Next steps:"
    echo "1. Run 'tlp-stat' to check TLP status"
    echo "2. Run 'sudo powertop' to analyze power consumption"
    echo "3. Reboot your system for all changes to take effect"
    echo "4. Use the monitoring scripts in the scripts/ directory"
}

# Run main function if script is executed directly
if [[ "${BASH_SOURCE[0]}" == "${0}" ]]; then
    main "$@"
fi