#!/bin/bash

# Color definitions for terminal output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
BLUE='\033[0;34m'
PURPLE='\033[0;35m'
CYAN='\033[0;36m'
WHITE='\033[1;37m'
NC='\033[0m' # No Color

# Logging functions
log_info() {
    echo -e "${BLUE}[INFO]${NC} $1"
}

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

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

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

log_step() {
    echo -e "${PURPLE}[STEP]${NC} $1"
}

log_config() {
    echo -e "${CYAN}[CONFIG]${NC} $1"
}

# Default values
service_name="komari-agent"
target_dir="/opt/komari"
github_proxy=""
install_version="" # New parameter for specifying version

# Parse install-specific arguments
komari_args=""
while [[ $# -gt 0 ]]; do
    case $1 in
        --install-dir)
            target_dir="$2"
            shift 2
            ;;
        --install-service-name)
            service_name="$2"
            shift 2
            ;;
        --install-ghproxy)
            github_proxy="$2"
            shift 2
            ;;
        --install-version)
            install_version="$2"
            shift 2
            ;;
        --install*)
            log_warning "Unknown install parameter: $1"
            shift
            ;;
        *)
            # Non-install arguments go to komari_args
            komari_args="$komari_args $1"
            shift
            ;;
    esac
done

# Remove leading space from komari_args if present
komari_args="${komari_args# }"

komari_agent_path="${target_dir}/agent"

if [ "$EUID" -ne 0 ]; then
    log_error "Please run as root"
    exit 1
fi

echo -e "${WHITE}===========================================${NC}"
echo -e "${WHITE}    Komari Agent Installation Script     ${NC}"
echo -e "${WHITE}===========================================${NC}"
echo ""
log_config "Installation configuration:"
log_config "  Service name: ${GREEN}$service_name${NC}"
log_config "  Install directory: ${GREEN}$target_dir${NC}"
log_config "  GitHub proxy: ${GREEN}${github_proxy:-"(direct)"}${NC}"
log_config "  Binary arguments: ${GREEN}$komari_args${NC}"
if [ -n "$install_version" ]; then
    log_config "  Specified agent version: ${GREEN}$install_version${NC}"
else
    log_config "  Agent version: ${GREEN}Latest${NC}"
fi
echo ""

# Function to uninstall the previous installation
uninstall_previous() {
    log_step "Checking for previous installation..."
    
    # Stop and disable service if it exists
    if command -v systemctl >/dev/null 2>&1 && systemctl list-unit-files | grep -q "${service_name}.service"; then
        log_info "Stopping and disabling existing systemd service..."
        systemctl stop ${service_name}.service
        systemctl disable ${service_name}.service
        rm -f "/etc/systemd/system/${service_name}.service"
        systemctl daemon-reload
    elif command -v rc-service >/dev/null 2>&1 && [ -f "/etc/init.d/${service_name}" ]; then
        log_info "Stopping and disabling existing OpenRC service..."
        rc-service ${service_name} stop
        rc-update del ${service_name} default
        rm -f "/etc/init.d/${service_name}"
    fi
    
    # Remove old binary if it exists
    if [ -f "$komari_agent_path" ]; then
        log_info "Removing old binary..."
        rm -f "$komari_agent_path"
    fi
}

# Uninstall previous installation
uninstall_previous

install_dependencies() {
    log_step "Checking and installing dependencies..."

    local deps="curl"
    local missing_deps=""
    for cmd in $deps; do
        if ! command -v $cmd >/dev/null 2>&1; then
            missing_deps="$missing_deps $cmd"
        fi
    done

    if [ -n "$missing_deps" ]; then
        # Check package manager and install dependencies
        if command -v apt >/dev/null 2>&1; then
            log_info "Using apt to install dependencies..."
            apt update
            apt install -y $missing_deps
        elif command -v yum >/dev/null 2>&1; then
            log_info "Using yum to install dependencies..."
            yum install -y $missing_deps
        elif command -v apk >/dev/null 2>&1; then
            log_info "Using apk to install dependencies..."
            apk add $missing_deps
        else
            log_error "No supported package manager found (apt/yum/apk)"
            exit 1
        fi
        
        # Verify installation
        for cmd in $missing_deps; do
            if ! command -v $cmd >/dev/null 2>&1; then
                log_error "Failed to install $cmd"
                exit 1
            fi
        done
        log_success "Dependencies installed successfully"
    else
        log_success "Dependencies already satisfied"
    fi
}

# Install dependencies
install_dependencies

arch=$(uname -m)
case $arch in
    x86_64)
        arch="amd64"
        ;;
    aarch64)
        arch="arm64"
        ;;
    *)
        log_error "Unsupported architecture: $arch"
        exit 1
        ;;
esac
log_info "Detected architecture: ${GREEN}$arch${NC}"

current_version=""
if [ -n "$install_version" ]; then
    log_info "Attempting to install specified version: ${GREEN}$install_version${NC}"
    current_version="$install_version"
else
    api_url="https://api.github.com/repos/komari-monitor/komari-agent/releases/latest"
    log_step "Fetching latest version from GitHub API..."
    current_version=$(curl -s "$api_url" | grep "tag_name" | cut -d'"' -f4)
    if [ -z "$current_version" ]; then
        log_error "Could not fetch latest version"
        exit 1
    fi
    log_success "Latest version fetched: ${GREEN}$current_version${NC}"
fi
log_success "Installing Komari Agent version: ${GREEN}$current_version${NC}"

# Construct download URL
file_name="komari-agent-linux-${arch}"
if [ -n "$github_proxy" ]; then
    # Use proxy for GitHub releases
    download_url="${github_proxy}/https://github.com/komari-monitor/komari-agent/releases/download/${current_version}/${file_name}"
else
    # Direct access to GitHub releases
    download_url="https://github.com/komari-monitor/komari-agent/releases/download/${current_version}/${file_name}"
fi

log_step "Creating installation directory: ${GREEN}$target_dir${NC}"
mkdir -p "$target_dir"

# Download binary
if [ -n "$github_proxy" ]; then
    log_step "Downloading $file_name via proxy..."
    log_info "URL: ${CYAN}$download_url${NC}"
else
    log_step "Downloading $file_name directly..."
    log_info "URL: ${CYAN}$download_url${NC}"
fi
curl -L -o "$komari_agent_path" "$download_url"
if [ $? -ne 0 ]; then
    log_error "Download failed"
    exit 1
fi

# Set executable permissions
chmod +x "$komari_agent_path"
log_success "Komari-agent installed to ${GREEN}$komari_agent_path${NC}"

# Detect init system and configure service
log_step "Configuring system service..."
if command -v systemctl >/dev/null 2>&1; then
    # Systemd service configuration
    log_info "Using systemd for service management"
    service_file="/etc/systemd/system/${service_name}.service"
    cat > "$service_file" << EOF
[Unit]
Description=Komari Agent Service
After=network.target

[Service]
Type=simple
ExecStart=${komari_agent_path} ${komari_args}
WorkingDirectory=${target_dir}
Restart=always
User=root

[Install]
WantedBy=multi-user.target
EOF

    # Reload systemd and start service
    systemctl daemon-reload
    systemctl enable ${service_name}.service
    systemctl start ${service_name}.service
    log_success "Systemd service configured and started"
elif command -v rc-service >/dev/null 2>&1; then
    # OpenRC service configuration
    log_info "Using OpenRC for service management"
    service_file="/etc/init.d/${service_name}"
    cat > "$service_file" << EOF
#!/sbin/openrc-run

name="Komari Agent Service"
description="Komari monitoring agent"
command="${komari_agent_path}"
command_args="${komari_args}"
command_user="root"
directory="${target_dir}"
pidfile="/run/${service_name}.pid"
retry="SIGTERM/30"

depend() {
    need net
    after network
}
EOF

    # Set permissions and enable service
    chmod +x "$service_file"
    rc-update add ${service_name} default
    rc-service ${service_name} start
    log_success "OpenRC service configured and started"
else
    log_error "Unsupported init system (neither systemd nor openrc found)"
    exit 1
fi

echo ""
echo -e "${WHITE}===========================================${NC}"
log_success "Komari-agent installation completed!"
log_config "Service: ${GREEN}$service_name${NC}"
log_config "Arguments: ${GREEN}$komari_args${NC}"
echo -e "${WHITE}===========================================${NC}"