updateScript for node

---
--- Generated by EmmyLua(https://github.com/EmmyLua)
--- Created by cdbab.
--- DateTime: 11/26/2024 5:12 AM
---
-- Node Update Script

local pastebinID = "yCChhW7d" -- Pastebin ID for node startup.lua
local pastebinURL = "https://pastebin.com/raw/" .. pastebinID
local startupScriptName = "startup.lua"
local localVersionFile = "version.txt" -- File to store the local version
local maxRetries = 5
local retryDelay = 4 -- seconds
local version = "1.0.4" -- Version of the update.lua

-- Function to check if the Pastebin file exists
local function checkPastebinFileExists()
    print("Checking if Pastebin file exists...")
    local response = http.get(pastebinURL)
    if response then
        response.close()
        print("Pastebin file exists.")
        return true
    else
        print("Pastebin file does not exist or cannot be accessed.")
        return false
    end
end

-- Function to read the local version
local function readLocalVersion()
    if fs.exists(localVersionFile) then
        local file = fs.open(localVersionFile, "r")
        local version = file.readLine()
        file.close()
        return version
    else
        return nil -- No local version exists
    end
end

-- Function to write the local version
local function writeLocalVersion(version)
    local file = fs.open(localVersionFile, "w")
    file.writeLine(version)
    file.close()
end

-- Function to fetch the remote version from Pastebin
local function fetchRemoteVersion()
    print("Fetching remote version from Pastebin...")
    local response = http.get(pastebinURL)
    if response then
        local content = response.readAll()
        response.close()

        -- Extract the version from the script content
        local remoteVersion = content:match('local version%s*=%s*"(.-)"')
        if remoteVersion then
            print("Remote version found: " .. remoteVersion)
            return remoteVersion
        else
            print("Failed to extract version from remote script.")
            return nil
        end
    else
        print("Failed to fetch remote script. Check network or Pastebin ID.")
        return nil
    end
end

-- Function to compare versions
local function isUpdateRequired(localVersion, remoteVersion)
    if not localVersion then
        print("No local version found. Update required.")
        return true
    end

    if localVersion ~= remoteVersion then
        print("Version mismatch: Local (" .. localVersion .. ") vs Remote (" .. remoteVersion .. "). Update required.")
        return true
    else
        print("Local version (" .. localVersion .. ") is up-to-date.")
        return false
    end
end

-- Function to attempt downloading the startup.lua script
local function fetchStartupScript()
    for attempt = 1, maxRetries do
        print("Attempt " .. attempt .. " to download " .. startupScriptName .. "...")

        -- Remove any existing, potentially corrupt startup.lua file
        if fs.exists(startupScriptName) then
            fs.delete(startupScriptName)
        end

        -- Attempt to download the script
        local success = shell.run("pastebin get " .. pastebinID .. " " .. startupScriptName)

        -- Check if the file was successfully downloaded
        if success and fs.exists(startupScriptName) then
            print("Successfully downloaded " .. startupScriptName .. " on attempt " .. attempt)
            return true
        else
            print("Failed to download " .. startupScriptName .. ". Retrying in " .. retryDelay .. " seconds...")
            sleep(retryDelay)
        end
    end

    -- If all attempts fail, return false
    return false
end

-- Main update logic
print("Starting update process...")

-- Check if the Pastebin file exists
if not checkPastebinFileExists() then
    print("Pastebin file does not exist. Aborting update.")
    return
end

-- Read local version
local localVersion = readLocalVersion()

-- Fetch remote version
local remoteVersion = fetchRemoteVersion()

-- Check if an update is required
if remoteVersion and isUpdateRequired(localVersion, remoteVersion) then
    -- Attempt to fetch the startup.lua script
    if fetchStartupScript() then
        -- Update local version
        writeLocalVersion(remoteVersion)
        print("Update successful. Rebooting...")
        os.reboot() -- Reboot the node to apply changes
    else
        print("Update failed after " .. maxRetries .. " attempts. Please check the network or Pastebin ID.")
    end
else
    print("No update required. Exiting.")
    os.reboot()
end