#Requires -Version 5.1
<#
    JbTecWiz Support Centre -- generated fix script

    Fault : Wi-Fi disconnects every few minutes and reconnects
    Fix   : Stop Windows powering the radio down
    Source: https://jbtecwiz.com/support/win-net-wifi-drops

    Run as     : Elevated PowerShell
    Expect     : 10 minutes
    Risk       : low
    Reversible : yes

    WHEN THIS IS THE RIGHT FIX
    It drops when idle or on battery. Try this first -- it costs a few
    minutes of battery life and fixes most of these.

    HOW TO UNDO IT
    powercfg with a value of 3 restores maximum power saving, and the Device
    Manager checkbox can simply be ticked again.

    This script walks the fix one step at a time and asks before each
    one. Steps with no command are things you do yourself -- it prints
    those and waits. Run with -DryRun to print without executing.

    --------------------------------------------------------------------
    NO WARRANTY - USE AT YOUR OWN RISK

    This script is provided by JbTecWiz as-is and with no warranty of any
    kind, express or implied. You run it entirely at your own risk.

    JbTecWiz accepts no liability for any loss or damage arising from its
    use, including but not limited to data loss, downtime, or configuration
    changes that turn out to be wrong for your system.

    You are responsible for reading this script before running it, for
    satisfying yourself that it suits the machine in front of you, and for
    having a working backup first. Some steps cannot be undone.
    --------------------------------------------------------------------
#>

[CmdletBinding()]
param(
    # Print every step and command without running anything.
    [switch]$DryRun,
    # Do not ask before each step. Read the script first if you use this.
    [switch]$Unattended
)

$ErrorActionPreference = 'Stop'
$script:Failed = 0

function Write-Rule { param([string]$Text)
    Write-Host ''
    Write-Host ('-' * 70) -ForegroundColor DarkGray
    if ($Text) { Write-Host $Text -ForegroundColor Cyan }
}

function Show-Prose { param([string]$Text, [string]$Colour = "Gray")
    if (-not $Text) { return }
    $words = $Text -split "\s+"; $line = "  "
    foreach ($w in $words) {
        if (($line.Length + $w.Length) -gt 74) { Write-Host $line -ForegroundColor $Colour; $line = "  " }
        $line += "$w "
    }
    if ($line.Trim()) { Write-Host $line -ForegroundColor $Colour }
}

function Invoke-Step {
    param(
        [int]$Number, [string]$Do, [string]$Why,
        [scriptblock]$Command, [switch]$Manual, [string]$Shell = "powershell"
    )
    Write-Rule "  Step $Number of 4"
    Show-Prose $Do "White"
    if ($Why) { Write-Host ""; Show-Prose $Why "DarkGray" }

    if ($Manual) {
        Write-Host ''
        Write-Host '  -> Do this yourself, then press Enter to carry on.' -ForegroundColor Yellow
        if (-not $Unattended -and -not $DryRun) { [void](Read-Host) }
        return
    }

    Write-Host ''
    foreach ($l in ($Command.ToString().Trim() -split "`n")) {
        Write-Host ("    " + $l.Trim()) -ForegroundColor Green
    }
    Write-Host ''

    if ($DryRun) { Write-Host "  (dry run -- not executed)" -ForegroundColor DarkGray; return }
    if (-not $Unattended) {
        $a = Read-Host "  Run this step? [Y]es / [S]kip / [Q]uit"
        if ($a -match "^[Qq]") { Write-Host "  Stopped at your request."; exit 0 }
        if ($a -match "^[Ss]") { Write-Host "  Skipped." -ForegroundColor DarkGray; return }
    }
    try { & $Command }
    catch {
        $script:Failed++
        Write-Host ("  Step $Number failed: " + $_.Exception.Message) -ForegroundColor Red
        Show-Prose "The rest of the fix may depend on this. Read the write-up before carrying on." "Red"
        if (-not $Unattended) {
            $c = Read-Host "  Carry on anyway? [y/N]"
            if ($c -notmatch "^[Yy]") { exit 1 }
        }
    }
}

Write-Rule
Write-Host '  Wi-Fi disconnects every few minutes and reconnects' -ForegroundColor White
Write-Host '  Stop Windows powering the radio down' -ForegroundColor Cyan
Write-Host ''
Write-Host '  Risk: low   Reversible   10 minutes'
Write-Host ''
Show-Prose 'No warranty. Use at your own risk - JbTecWiz accepts no liability. Read it before you run it, and have a backup.' 'DarkYellow'
Write-Rule

if (-not $Unattended -and -not $DryRun) {
    $go = Read-Host '  Ready? [y/N]'
    if ($go -notmatch "^[Yy]") { Write-Host "  Nothing was changed."; exit 0 }
}

Invoke-Step -Number 1 -Do 'Find the adapter and turn off the device''s own power saving.' -Command {
    Get-NetAdapter -Physical | Where-Object MediaType -eq 'Native 802.11' | Format-Table Name,InterfaceDescription
}

Invoke-Step -Number 2 -Do 'Disable the allow-to-turn-off setting.' -Why 'The device manager checkbox and this WMI property are the same setting. Reading it here tells you whether the checkbox was ever actually applied -- Group Policy and driver updates both reset it.' -Command {
    $a = Get-NetAdapter -Name 'Wi-Fi'
    Get-CimInstance -Namespace root\wmi -ClassName MSPower_DeviceEnable | Where-Object InstanceName -like "*$($a.PnPDeviceID.Replace('\','\\'))*"
}

Invoke-Step -Number 3 -Do 'Simplest reliable route: open Device Manager, the adapter''s Properties, Power Management tab, and clear "Allow the computer to turn off this device to save power".' -Command {
    cmd.exe /c 'devmgmt.msc'
}

Invoke-Step -Number 4 -Do 'Then stop the power plan doing the same thing at a higher level.' -Why 'That GUID pair is Wireless Adapter Settings -> Power Saving Mode. Zero is maximum performance, on mains and on battery.' -Command {
    cmd.exe /c 'powercfg /setacvalueindex SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 0 & powercfg /setdcvalueindex SCHEME_CURRENT 19cbb8fa-5279-450e-9fac-8a3d5fedd0c1 12bbebe6-58d6-4636-95bb-3217ef867c1a 0 & powercfg /setactive SCHEME_CURRENT'
}

Write-Rule "  Confirm it worked"
Show-Prose 'Leave the machine idle on battery for half an hour and check the WLAN log is quiet.' 'White'
Write-Host ''
if (-not $DryRun) {
    Get-WinEvent -LogName 'Microsoft-Windows-WLAN-AutoConfig/Operational' -MaxEvents 40 | Where-Object Id -in 8003,8002,11004 | Format-Table TimeCreated,Id,Message -Wrap
}

Write-Rule
if ($script:Failed -gt 0) {
    Write-Host ("  Finished with " + $script:Failed + " failed step(s).") -ForegroundColor Yellow
    Show-Prose 'Read the full write-up at https://jbtecwiz.com/support/win-net-wifi-drops' 'Yellow'
} else {
    Write-Host '  Finished.' -ForegroundColor Green
}
Write-Host ''
Show-Prose 'To undo: powercfg with a value of 3 restores maximum power saving, and the Device Manager checkbox can simply be ticked again.' 'DarkGray'
Write-Rule