name: Generate WinUtil title screen

on:
  workflow_dispatch:

permissions:
  contents: read

concurrency:
  group: winutil-title-screen
  cancel-in-progress: true

jobs:
  generate:
    runs-on: windows-latest
    timeout-minutes: 15
    env:
      WINUTIL_CAPTURE_WIDTH: "1920"
      WINUTIL_CAPTURE_HEIGHT: "1080"

    defaults:
      run:
        shell: pwsh

    steps:
      - name: Checkout repository
        uses: actions/checkout@v7
        with:
          ref: main
          persist-credentials: false

      - name: Install uv and Python
        uses: astral-sh/setup-uv@v10.2.0
        with:
          version: "0.12.0"
          python-version: "3.13"
          enable-cache: false

      - name: Set display resolution
        run: |
          # Set-DisplayResolution is provided by Windows PowerShell's ServerCore
          # module, so this step intentionally calls powershell.exe from pwsh.
          & powershell.exe -NoLogo -NoProfile -Command @'
          Set-DisplayResolution `
              -Width $env:WINUTIL_CAPTURE_WIDTH `
              -Height $env:WINUTIL_CAPTURE_HEIGHT `
              -Force
          '@

          if ($LASTEXITCODE -ne 0) {
              throw "Failed to set the runner display resolution."
          }

          Add-Type @"
          using System.Runtime.InteropServices;

          public static class ResolutionCheck {
              [DllImport("user32.dll")]
              public static extern int GetSystemMetrics(int index);
          }
          "@

          $actualWidth = [ResolutionCheck]::GetSystemMetrics(0)
          $actualHeight = [ResolutionCheck]::GetSystemMetrics(1)
          if (
              $actualWidth -ne [int]$env:WINUTIL_CAPTURE_WIDTH -or
              $actualHeight -ne [int]$env:WINUTIL_CAPTURE_HEIGHT
          ) {
              throw (
                  "The hosted runner rejected the requested resolution. " +
                  "Requested: $env:WINUTIL_CAPTURE_WIDTH" +
                  "x$env:WINUTIL_CAPTURE_HEIGHT; " +
                  "actual: ${actualWidth}x${actualHeight}."
              )
          }

      - name: Report display environment
        run: |
          Add-Type @"
          using System.Runtime.InteropServices;

          public static class DisplayInfo {
              [DllImport("user32.dll")]
              public static extern int GetSystemMetrics(int index);
          }
          "@

          $width = [DisplayInfo]::GetSystemMetrics(0)
          $height = [DisplayInfo]::GetSystemMetrics(1)
          $sessionId = [Diagnostics.Process]::GetCurrentProcess().SessionId

          Write-Host "Resolution: ${width}x${height}"
          Write-Host "Session ID: $sessionId"
          Write-Host "User: $env:USERNAME"

      - name: Compile WinUtil
        run: |
          Set-ExecutionPolicy Bypass -Scope Process -Force
          ./Compile.ps1

      - name: Launch WinUtil
        run: |
          $scriptPath = Join-Path $env:GITHUB_WORKSPACE "winutil.ps1"
          $command = "& '$scriptPath'"
          $bytes = [Text.Encoding]::Unicode.GetBytes($command)
          $encodedCommand = [Convert]::ToBase64String($bytes)

          # Hide the console host while leaving the WPF window available.
          $process = Start-Process powershell.exe -ArgumentList @(
              "-NoLogo",
              "-NoProfile",
              "-ExecutionPolicy", "Bypass",
              "-EncodedCommand", $encodedCommand
          ) -WindowStyle Hidden -PassThru

          "WINUTIL_HOST_PID=$($process.Id)" |
              Out-File $env:GITHUB_ENV -Append -Encoding utf8

          $deadline = (Get-Date).AddSeconds(90)
          do {
              Start-Sleep -Seconds 2
              # A versioned title excludes the unversioned console host.
              $window = Get-Process |
                  Where-Object { $_.MainWindowTitle -match '^WinUtil\s+\d' } |
                  Select-Object -First 1
          } until ($window -or (Get-Date) -ge $deadline)

          if (-not $window) {
              throw "WinUtil did not expose a window within 90 seconds."
          }

          Write-Host "WinUtil HWND: $($window.MainWindowHandle)"
          Write-Host "WinUtil title: $($window.MainWindowTitle)"

          # The exact HWND avoids desktop-enumeration ambiguity. Python validates
          # the title and WPF class before using it.
          "WINUTIL_HWND=$($window.MainWindowHandle)" |
              Out-File $env:GITHUB_ENV -Append -Encoding utf8

      - name: Generate title screen
        working-directory: tools/title-screen
        run: |
          & uv run --locked python automate_title_screen.py `
              --output ..\..\docs\src\assets\branding\title-screen.png 2>&1 |
              Tee-Object -FilePath "$env:RUNNER_TEMP\title-screen-capture.log"

          if ($LASTEXITCODE -ne 0) {
              throw "Title-screen automation exited with code $LASTEXITCODE."
          }

      - name: Create title-screen update pull request
        id: cpr
        uses: peter-evans/create-pull-request@v8
        with:
          token: ${{ secrets.AUTO_MERGE }}
          add-paths: docs/src/assets/branding/title-screen.png
          base: main
          branch: title-screen-update
          delete-branch: true
          commit-message: "docs: update WinUtil title screen"
          title: "docs: update WinUtil title screen"
          body: |
            Regenerates the WinUtil Light and Dark title-screen composite from the current main branch.

            Source workflow: ${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}
          labels: |
            automated
            documentation
            skip-changelog

      - name: Report pull request
        if: steps.cpr.outputs.pull-request-url
        env:
          PR_OPERATION: ${{ steps.cpr.outputs.pull-request-operation }}
          PR_URL: ${{ steps.cpr.outputs.pull-request-url }}
        run: |
          Write-Host "Pull request $env:PR_OPERATION`: $env:PR_URL"

      - name: Inspect UI Automation on failure
        if: failure()
        continue-on-error: true
        working-directory: tools/title-screen
        run: |
          uv run --locked python inspect_winutil.py `
              "$env:RUNNER_TEMP\winutil-title-screen-inspect.txt"

      - name: Upload failure diagnostics
        if: failure()
        uses: actions/upload-artifact@v7
        with:
          name: winutil-title-screen-failure-${{ github.run_number }}
          path: |
            docs/src/assets/branding/title-screen.png
            ${{ runner.temp }}/title-screen-capture.log
            ${{ runner.temp }}/winutil-title-screen-inspect.txt
          if-no-files-found: warn
          retention-days: 14

      - name: Close WinUtil
        if: always()
        run: |
          if ($env:WINUTIL_HOST_PID) {
              Stop-Process `
                  -Id ([int]$env:WINUTIL_HOST_PID) `
                  -Force `
                  -ErrorAction SilentlyContinue
          }