Set-SpaceWallpapers.ps1

# Set-SpaceWallpapers.ps1
# MULTI-MONITOR wallpaper using ONLY James Webb Space Telescope (JWST) photos.
# Primary source: scraping of esawebb.org (categories sorted by ranking).
# Fallback: Wikimedia Commons (category "Images by the James Webb Space Telescope").
# Fit mode: "Fit" (whole image, no cropping). Per-monitor wallpapers via the IDesktopWallpaper COM API.
#
# Usage:
#   .\Set-SpaceWallpapers.ps1             -> changes ALL monitors (used by the scheduled task)
#   .\Set-SpaceWallpapers.ps1 -Monitor 0  -> changes only the monitor with index 0 (0-based)
#   .\Set-SpaceWallpapers.ps1 -GUI        -> opens the chooser window (used by the desktop icon)

param([int]$Monitor = -1, [switch]$GUI)

$ErrorActionPreference = 'Stop'

# Folder where this script lives (makes everything portable to any PC/path)
$baseDir = if ($PSScriptRoot) { $PSScriptRoot } else { Split-Path -Parent $MyInvocation.MyCommand.Path }
$imgDir  = Join-Path $baseDir 'images'
$logFile = Join-Path $baseDir 'nasa-wallpaper.log'

$ua          = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36'
$esaCats     = @('nebulae', 'anniversary', 'galaxies', 'stars')   # esawebb categories (sorted by ranking)
$maxDimDefault = 3840                                             # max side of the saved image (px)
$POS_FIT     = 3                                                  # 3 = DWPOS_FIT ("Fit")

$script:pool       = $null   # list of image references (esawebb ids or Commons titles)
$script:poolSource = ''      # 'esawebb' | 'commons'

function Write-Log($msg) {
    $line = '{0}  {1}' -f (Get-Date -Format 'yyyy-MM-dd HH:mm:ss'), $msg
    Add-Content -Path $logFile -Value $line
    Write-Host $line
}

# IDesktopWallpaper COM interface definition (methods must be in the exact vtable order)
$dwCode = @'
using System;
using System.Runtime.InteropServices;

[StructLayout(LayoutKind.Sequential)]
public struct RECT { public int Left, Top, Right, Bottom; }

[ComImport, Guid("B92B56A9-8B55-4E14-9A89-0199BBB6F93B"), InterfaceType(ComInterfaceType.InterfaceIsIUnknown)]
public interface IDesktopWallpaper {
    void SetWallpaper([MarshalAs(UnmanagedType.LPWStr)] string monitorID, [MarshalAs(UnmanagedType.LPWStr)] string wallpaper);
    [return: MarshalAs(UnmanagedType.LPWStr)] string GetWallpaper([MarshalAs(UnmanagedType.LPWStr)] string monitorID);
    [return: MarshalAs(UnmanagedType.LPWStr)] string GetMonitorDevicePathAt(uint monitorIndex);
    uint GetMonitorDevicePathCount();
    void GetMonitorRECT([MarshalAs(UnmanagedType.LPWStr)] string monitorID, out RECT displayRect);
    void SetBackgroundColor(uint color);
    uint GetBackgroundColor();
    void SetPosition(int position);
}

[ComImport, Guid("C2CF3110-460E-4fc1-B9D0-8A1C0C9CC4BD")]
public class DesktopWallpaperClass { }

public static class DW {
    static IDesktopWallpaper _i;
    static IDesktopWallpaper I() { if (_i == null) _i = (IDesktopWallpaper)new DesktopWallpaperClass(); return _i; }
    public static uint Count() { return I().GetMonitorDevicePathCount(); }
    public static string Id(uint i) { return I().GetMonitorDevicePathAt(i); }
    public static int Width(string id)  { RECT r; I().GetMonitorRECT(id, out r); return r.Right - r.Left; }
    public static int Height(string id) { RECT r; I().GetMonitorRECT(id, out r); return r.Bottom - r.Top; }
    public static void Set(string id, string path) { I().SetWallpaper(id, path); }
    public static void Pos(int p) { I().SetPosition(p); }
}
'@

# esawebb.org scraping: returns the image ids of the categories, in ranking order (deduped).
function Get-EsawebbPool {
    $ids = New-Object System.Collections.ArrayList
    $skip = @('archive', 'search', 'potm', 'viewall', 'categories')
    foreach ($c in $esaCats) {
        try {
            $html = (Invoke-WebRequest -Uri "https://esawebb.org/images/archive/category/$c/?sort=-priority" -UserAgent $ua -TimeoutSec 60 -UseBasicParsing).Content
            foreach ($m in [regex]::Matches($html, 'href="/images/([\w-]+)/"')) {
                $id = $m.Groups[1].Value
                if ($id -notin $skip -and $ids -notcontains $id) { [void]$ids.Add($id) }
            }
        }
        catch { Write-Log "Scraping of category '$c' failed: $($_.Exception.Message)" }
    }
    return $ids
}

# Wikimedia Commons fallback: image file titles of the JWST category.
function Get-CommonsPool {
    $api = 'https://commons.wikimedia.org/w/api.php'
    $cat = 'Category:Images by the James Webb Space Telescope'
    $u = "$api`?action=query&format=json&list=categorymembers&cmtitle=$([uri]::EscapeDataString($cat))&cmtype=file&cmlimit=500"
    $r = Invoke-RestMethod -Uri $u -TimeoutSec 60
    return @($r.query.categorymembers | Where-Object { $_.title -match '\.(jpg|jpeg|png)$' } | ForEach-Object { $_.title })
}

# URL of the Commons thumbnail resized to $width px wide.
function Get-CommonsThumbUrl($title, $width) {
    $api = 'https://commons.wikimedia.org/w/api.php'
    $u = "$api`?action=query&format=json&prop=imageinfo&iiprop=url&iiurlwidth=$([int]$width)&titles=$([uri]::EscapeDataString($title))"
    $r = Invoke-RestMethod -Uri $u -TimeoutSec 60
    return (($r.query.pages.PSObject.Properties.Value).imageinfo[0]).thumburl
}

# Builds the pool only once: esawebb first, otherwise Commons.
function Initialize-Pool {
    if ($script:pool -and $script:pool.Count -gt 0) { return }
    $ids = Get-EsawebbPool
    if ($ids.Count -ge 10) {
        $script:pool = $ids; $script:poolSource = 'esawebb'
        Write-Log "ESA/Webb pool (ranking): $($ids.Count) images."
    }
    else {
        Write-Log "ESA/Webb scraping insufficient ($($ids.Count)) -> Wikimedia Commons fallback."
        $script:pool = Get-CommonsPool; $script:poolSource = 'commons'
        Write-Log "Commons pool: $($script:pool.Count) images."
    }
}

# Downloads $url, resizes it if the longest side exceeds $maxDim, saves JPEG to $destPath.
# Returns the ORIGINAL dimensions as a hashtable @{Width;Height}.
function Get-PreparedImage($url, $destPath, $maxDim) {
    Add-Type -AssemblyName System.Drawing
    $tmp = [System.IO.Path]::GetTempFileName()
    try {
        Invoke-WebRequest -Uri $url -UserAgent $ua -OutFile $tmp -TimeoutSec 300 -UseBasicParsing
        $img = [System.Drawing.Image]::FromFile($tmp)
        $w = $img.Width; $h = $img.Height
        $maxSide = [math]::Max($w, $h)
        if ($maxSide -gt $maxDim) {
            $scale = $maxDim / $maxSide
            $nw = [int]($w * $scale); $nh = [int]($h * $scale)
            $bmp = New-Object System.Drawing.Bitmap $nw, $nh
            $g = [System.Drawing.Graphics]::FromImage($bmp)
            $g.InterpolationMode = [System.Drawing.Drawing2D.InterpolationMode]::HighQualityBicubic
            $g.DrawImage($img, 0, 0, $nw, $nh)
            $g.Dispose(); $img.Dispose()
            $bmp.Save($destPath, [System.Drawing.Imaging.ImageFormat]::Jpeg)
            $bmp.Dispose()
        }
        else {
            $img.Dispose()
            Copy-Item $tmp $destPath -Force
        }
        return @{ Width = $w; Height = $h }
    }
    finally { Remove-Item $tmp -Force -ErrorAction SilentlyContinue }
}

# Sets the wallpaper of a single monitor (0-based index). Returns $true on success.
function Set-OneMonitor($index, $usedRefs) {
    $monId = [DW]::Id([uint32]$index)
    $w = [DW]::Width($monId)
    $h = [DW]::Height($monId)
    if ($w -le 0 -or $h -le 0) { Write-Log "Monitor [$index] not active: skipping."; return $false }

    $maxDim = [math]::Max($maxDimDefault, [math]::Max($w, $h))
    $candidates = @($script:pool | Where-Object { $usedRefs -notcontains $_ } | Sort-Object { Get-Random })
    if ($candidates.Count -eq 0) { $candidates = @($script:pool | Sort-Object { Get-Random }) }

    foreach ($ref in ($candidates | Select-Object -First 6)) {
        try {
            if ($script:poolSource -eq 'esawebb') {
                $url = "https://esawebb.org/media/archives/images/large/$ref.jpg"
            }
            else {
                $url = Get-CommonsThumbUrl $ref ([math]::Max($w, 2560))
            }
            $safe = ($ref -replace '[^\w\-]', '_')
            $dest = Join-Path $imgDir ("mon$index-$safe.jpg")
            $dims = Get-PreparedImage $url $dest $maxDim
            [DW]::Set($monId, $dest)
            [void]$usedRefs.Add($ref)
            Write-Log "Monitor [$index] ($($w)x$($h)) <- JWST [$($script:poolSource)] '$ref' (orig $($dims.Width)x$($dims.Height))"
            return $true
        }
        catch { Write-Log "Monitor [$index]: '$ref' failed ($($_.Exception.Message)), trying another." }
    }
    return $false
}

# Changes the wallpapers of the passed monitor indices; returns how many were updated.
function Invoke-Switch($indices) {
    Initialize-Pool
    if (-not $script:pool -or $script:pool.Count -eq 0) { Write-Log "ERROR: no images available."; return 0 }
    $used = New-Object System.Collections.ArrayList
    $ok = 0
    foreach ($i in $indices) {
        try { if (Set-OneMonitor $i $used) { $ok++ } }
        catch { Write-Log "Monitor [$i]: error ($($_.Exception.Message))." }
    }
    [DW]::Pos($POS_FIT)   # "Fit" for all monitors
    return $ok
}

# Chooser window (Windows Forms)
function Show-Chooser {
    Add-Type -AssemblyName System.Windows.Forms
    Add-Type -AssemblyName System.Drawing
    $count = [int][DW]::Count()

    $form = New-Object System.Windows.Forms.Form
    $form.Text = 'JWST Wallpapers'
    $form.StartPosition = 'CenterScreen'
    $form.FormBorderStyle = 'FixedDialog'
    $form.MaximizeBox = $false
    $form.MinimizeBox = $false
    $form.Font = New-Object System.Drawing.Font('Segoe UI', 9)

    $lbl = New-Object System.Windows.Forms.Label
    $lbl.Text = 'Which wallpaper do you want to change? (James Webb photos)'
    $lbl.AutoSize = $true
    $lbl.Location = New-Object System.Drawing.Point(15, 15)
    $form.Controls.Add($lbl)

    $y = 45
    $radios = New-Object System.Collections.ArrayList

    $rbAll = New-Object System.Windows.Forms.RadioButton
    $rbAll.Text = "All monitors ($count)"
    $rbAll.Location = New-Object System.Drawing.Point(20, $y)
    $rbAll.AutoSize = $true
    $rbAll.Checked = $true
    $form.Controls.Add($rbAll)
    $y += 28

    for ($i = 0; $i -lt $count; $i++) {
        $monId = [DW]::Id([uint32]$i)
        $w = [DW]::Width($monId); $h = [DW]::Height($monId)
        $parts = $monId -split '#'
        $model = if ($parts.Count -ge 2) { $parts[1] } else { 'Monitor' }
        $rb = New-Object System.Windows.Forms.RadioButton
        $rb.Text = "Monitor $($i + 1) - $model ($($w)x$($h))"
        $rb.Location = New-Object System.Drawing.Point(20, $y)
        $rb.AutoSize = $true
        $rb.Tag = $i
        $form.Controls.Add($rb)
        [void]$radios.Add($rb)
        $y += 28
    }

    $y += 6
    $status = New-Object System.Windows.Forms.Label
    $status.Text = ''
    $status.AutoSize = $true
    $status.MaximumSize = New-Object System.Drawing.Size(340, 0)
    $status.Location = New-Object System.Drawing.Point(20, $y)
    $status.ForeColor = [System.Drawing.Color]::DimGray
    $form.Controls.Add($status)
    $y += 40

    $btnGo = New-Object System.Windows.Forms.Button
    $btnGo.Text = 'Change'
    $btnGo.Location = New-Object System.Drawing.Point(185, $y)
    $btnGo.Size = New-Object System.Drawing.Size(80, 28)
    $form.Controls.Add($btnGo)

    $btnClose = New-Object System.Windows.Forms.Button
    $btnClose.Text = 'Close'
    $btnClose.Location = New-Object System.Drawing.Point(275, $y)
    $btnClose.Size = New-Object System.Drawing.Size(80, 28)
    $btnClose.Add_Click({ $form.Close() })
    $form.Controls.Add($btnClose)

    $form.ClientSize = New-Object System.Drawing.Size(375, ($y + 44))
    $form.AcceptButton = $btnGo

    $btnGo.Add_Click({
        if ($rbAll.Checked) {
            $indices = 0..($count - 1)
        }
        else {
            $sel = $radios | Where-Object { $_.Checked } | Select-Object -First 1
            $indices = @([int]$sel.Tag)
        }
        $btnGo.Enabled = $false; $btnClose.Enabled = $false
        $status.ForeColor = [System.Drawing.Color]::DimGray
        $status.Text = 'Changing, please wait...'
        $form.Refresh()
        [System.Windows.Forms.Application]::DoEvents()
        try {
            $n = Invoke-Switch $indices
            $status.ForeColor = [System.Drawing.Color]::ForestGreen
            $status.Text = "Done: $n wallpaper(s) updated."
        }
        catch {
            $status.ForeColor = [System.Drawing.Color]::Firebrick
            $status.Text = "Error: $($_.Exception.Message)"
        }
        $btnGo.Enabled = $true; $btnClose.Enabled = $true
    })

    [void]$form.ShowDialog()
}

try {
    if (-not (Test-Path $imgDir)) { New-Item -ItemType Directory -Path $imgDir -Force | Out-Null }
    Add-Type -TypeDefinition $dwCode

    $count = [int][DW]::Count()
    if ($count -le 0) { Write-Log "ERROR: no monitor detected."; exit 1 }

    if ($GUI) {
        Show-Chooser
    }
    elseif ($Monitor -ge 0) {
        if ($Monitor -ge $count) { Write-Log "ERROR: monitor $Monitor does not exist (valid indices 0..$($count - 1))."; exit 1 }
        $n = Invoke-Switch @($Monitor)
        Write-Log "Completed: updated $n monitor (index $Monitor)."
    }
    else {
        $n = Invoke-Switch (0..($count - 1))
        Write-Log "Completed: wallpapers set on $n of $count monitors."
    }
}
catch {
    Write-Log "ERROR: $($_.Exception.Message)"
    exit 1
}