#!/bin/bash

# Package Availability Checker for Live Systems
# Checks what packages are available before attempting installation

set -e

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

log() { echo -e "${BLUE}[INFO]${NC} $1"; }
success() { echo -e "${GREEN}[FOUND]${NC} $1"; }
warning() { echo -e "${YELLOW}[MISSING]${NC} $1"; }

echo -e "${GREEN}=== Package Availability Checker ===${NC}"
echo "Checking package availability for LVM migration..."
echo

# Detect distribution
if [ -f /etc/os-release ]; then
    . /etc/os-release
    echo "Distribution: $PRETTY_NAME"
    echo "ID: $ID"
    echo "Version: $VERSION_ID"
    echo
fi

# Function to check if a package exists in repositories
check_package() {
    local pkg="$1"
    if apt-cache show "$pkg" >/dev/null 2>&1; then
        success "$pkg"
        return 0
    else
        warning "$pkg"
        return 1
    fi
}

# Function to check multiple package alternatives
check_alternatives() {
    local desc="$1"
    shift
    local packages=("$@")
    
    echo -e "${BLUE}$desc:${NC}"
    local found=0
    for pkg in "${packages[@]}"; do
        if check_package "$pkg"; then
            ((found++))
        fi
    done
    
    if [ $found -eq 0 ]; then
        echo -e "  ${RED}⚠ No packages found for $desc${NC}"
    fi
    echo
}

echo "Updating package cache..."
apt update >/dev/null 2>&1 || warning "Could not update package cache"
echo

# Check critical packages
total_missing=0

check_alternatives "LVM Tools" "lvm2" "lvm"
check_alternatives "Device Mapper" "dmsetup" "device-mapper"
check_alternatives "Cryptsetup" "cryptsetup" "cryptsetup-bin"
check_alternatives "Filesystem Tools" "e2fsprogs" "dosfstools" "parted"
check_alternatives "Backup Tools" "rsync" "pv"
check_alternatives "GRUB EFI" "grub-efi-amd64" "grub-efi" "grub-efi-amd64-bin"
check_alternatives "GRUB PC" "grub-pc-bin" "grub-pc"
check_alternatives "GRUB Common" "grub-common" "grub2-common"
check_alternatives "Initramfs" "initramfs-tools" "dracut"
check_alternatives "System Tools" "util-linux" "coreutils" "bc"

echo -e "${BLUE}=== Summary ===${NC}"
echo -e "${GREEN}✓ Package availability checked${NC}"
echo "Most packages should be available for installation."

echo
echo "To install packages, run:"
echo "  sudo ./emergency_install.sh"
echo
echo "To check individual commands after installation:"
echo "  command -v lvm && echo 'LVM available'"
echo "  command -v cryptsetup && echo 'Cryptsetup available'"
echo "  command -v grub-install && echo 'GRUB available'"