#!/bin/bash

# --- Main Script ---

# This script presents a menu of software packages defined in a remote
# configuration file. The user can select a package, and the script
# will download the corresponding files. It includes a feature to show
# a diff and ask for confirmation before overwriting existing config files.
# It can also check for updates to already-installed scripts.

# --- Functions ---

# A simple function to log messages with a consistent format.
log() {
    echo "[$1] $2"
}

# New function to get the version from a local script file.
# It reads the first 5 lines and extracts the version number.
get_local_version() {
    local file_path="$1"
    if [[ -f "${file_path}" ]]; then
        # Grep for the version line, then use awk to get the last field.
        head -n 5 "${file_path}" | grep -m 1 "^# Version:" | awk '{print $NF}'
    else
        echo "0.0.0" # Return a base version if file doesn't exist.
    fi
}

# New function to compare two version strings (e.g., "1.2.0" vs "1.10.0").
# Returns 0 if v1 is newer, 1 if they are the same or v2 is newer.
is_version_greater() {
    local v1=$1
    local v2=$2
    # Use sort's version sorting capability to find the "highest" version.
    # If the highest version is v1, then v1 > v2.
    if [[ "$(printf '%s\n' "$v1" "$v2" | sort -V | head -n 1)" != "$v1" ]]; then
        return 0 # v1 is greater
    else
        return 1 # v1 is not greater (equal or less)
    fi
}

# --- Main Logic ---

# Generate a unique temporary filename with a timestamp.
conf_file="packages.conf.$(date +%Y%m%d%H%M%S)"

# Set up a trap to delete the temporary file on exit.
trap 'rm -f "${conf_file}"' EXIT

# Download the configuration file.
log "🔄" "Downloading configuration file..."
if ! curl -fsSL -o "${conf_file}" "https://git.technopunk.space/tomi/Scripts/raw/branch/main/packages.conf"; then
    log "❌" "Error: Failed to download packages.conf. Exiting."
    exit 1
fi
log "✅" "Configuration file downloaded successfully."

# Source the configuration file to load the SCRIPT_PACKAGES associative array.
source "${conf_file}"

# --- Update Check & User Interface ---

echo "-------------------------------------"
echo "        Script Downloader            "
echo "-------------------------------------"

# Create an array of options from the package names.
# We will modify this array to show installation and update status.
declare -a options
package_keys=("${!SCRIPT_PACKAGES[@]}")

log "🔎" "Checking for updates..."
for key in "${package_keys[@]}"; do
    # The config format is now "VERSION|URL1 URL2..."
    config_value="${SCRIPT_PACKAGES[$key]}"
    remote_version=$(echo "${config_value}" | cut -d'|' -f1)
    
    # Get just the URLs and assume the first URL is the main script to check.
    urls=$(echo "${config_value}" | cut -d'|' -f2-)
    read -r -a url_array <<< "$urls"
    main_script_filename=$(basename "${url_array[0]}")

    # Get the local version of the main script file.
    local_version=$(get_local_version "${main_script_filename}")

    status=""
    if [[ -f "${main_script_filename}" ]]; then
        status=" (Installed: v${local_version})"
        # Compare versions
        if is_version_greater "$remote_version" "$local_version"; then
            status+=" [Update available: v${remote_version}]"
        fi
    fi
    options+=("${key}${status}")
done
echo

options+=("Quit") # Add a Quit option to the menu.

# Set the prompt for the select menu.
PS3="Please enter your choice: "

# Display the menu and handle user input.
# Setting COLUMNS=1 forces the select menu to display vertically.
COLUMNS=1
select choice_with_status in "${options[@]}"; do
    # Strip the status message from the choice for key lookup
    choice=$(echo "${choice_with_status}" | sed 's/ (.*//')
    
    case "${choice}" in
        "Quit")
            log "👋" "Exiting."
            break # Exit the select loop.
            ;;
        *)
            # Check if the user's choice is a valid package name.
            if [[ -n "${SCRIPT_PACKAGES[$choice]}" ]]; then
                echo
                log "⬇️" "Processing package: '${choice}'..."
                
                # Get the config value and split it into version and URLs
                config_value="${SCRIPT_PACKAGES[$choice]}"
                remote_version=$(echo "${config_value}" | cut -d'|' -f1)
                urls_to_download=$(echo "${config_value}" | cut -d'|' -f2-)
                
                read -r -a urls_to_download_array <<< "$urls_to_download"

                for url in "${urls_to_download_array[@]}"; do
                    filename=$(basename "${url}")
                    # If it's a .conf file AND it already exists, ask to overwrite.
                    if [[ "${filename}" == *.conf && -f "${filename}" ]]; then
                        log "->" "Found existing config file: '${filename}'."
                        tmp_file=$(mktemp)

                        if curl -fsSL -o "${tmp_file}" "${url}"; then
                            log "🔎" "Comparing versions..."
                            echo "-------------------- DIFF START --------------------"
                            if command -v colordiff &> /dev/null; then
                                colordiff -u "${filename}" "${tmp_file}"
                            else
                                # Attempt to use diff's color option, which is common.
                                diff --color=always -u "${filename}" "${tmp_file}" 2>/dev/null || diff -u "${filename}" "${tmp_file}"
                            fi
                            echo "--------------------- DIFF END ---------------------"
                            
                            read -p "Do you want to overwrite '${filename}'? (y/N) " -n 1 -r REPLY
                            echo

                            if [[ $REPLY =~ ^[Yy]$ ]]; then
                                mv "${tmp_file}" "${filename}"
                                log "✅" "Updated '${filename}'."
                            else
                                rm "${tmp_file}"
                                log "🤷" "Kept existing version of '${filename}'."
                            fi
                        else
                            log "❌" "Error: Failed to download new version of '${filename}' for comparison."
                            rm -f "${tmp_file}"
                        fi
                    else
                        # Original download logic for all other files.
                        log "->" "Downloading '${filename}'..."
                        if curl -fsSL -o "${filename}" "${url}"; then
                            log "✅" "Successfully downloaded '${filename}'."
                            if [[ "${filename}" == *.sh ]]; then
                                chmod +x "${filename}"
                                log "🤖" "Made '${filename}' executable."
                            fi
                        else
                            log "❌" "Error: Failed to download '${filename}'."
                        fi
                    fi
                done
                echo
                log "📦" "Package processing complete."
                break
            else
                echo "Invalid selection. Please try again."
            fi
            ;;
    esac
done