tetris.ps1

[System.Console]::CursorVisible = $false

Register-EngineEvent -SourceIdentifier PowerShell.Exiting -Action {
	[System.Console]::CursorVisible = $true
} | Out-Null

$width = 10
$height = 20
$script:field = New-Object 'object[]' $height
for ($i = 0; $i -lt $height; $i++) {
	$script:field[$i] = New-Object 'int[]' $width
}

$shapes = @(
	@( @(1,1,1,1) ),
	@( @(1,1), @(1,1) ),
	@( @(0,1,0), @(1,1,1) ),
	@( @(1,0), @(1,0), @(1,1) ),
	@( @(0,1), @(0,1), @(1,1) ),
	@( @(1,0), @(1,1), @(0,1) ),
	@( @(0,1), @(1,1), @(1,0) )
)

$score = 0
$gameOver = $false
$currentShape = $null
$nextShape = $null
$lastUpdate = [DateTime]::Now
$fallInterval = 800
$previousFrame = @()

for ($i = 0; $i -lt $height; $i++) {
	$previousFrame += @("")
}

function Get-NewShape {
	$index = Get-Random -Minimum 0 -Maximum $shapes.Length
	$shape = $shapes[$index]
	return @{
		Shape = $shape
		X = [math]::Floor(($width - $shape[0].Length) / 2)
		Y = 0
	}
}

function Test-Collision {
	param($shape, $x, $y)
	for ($i = 0; $i -lt $shape.Shape.Length; $i++) {
		for ($j = 0; $j -lt $shape.Shape[$i].Length; $j++) {
			if ($shape.Shape[$i][$j] -ne 0) {
				$fieldX = $x + $j
				$fieldY = $y + $i
				if ($fieldX -lt 0 -or $fieldX -ge $width -or $fieldY -ge $height) {
					return $true
				}
				if ($fieldY -ge 0 -and $script:field[$fieldY][$fieldX] -ne 0) {
					return $true
				}
			}
		}
	}
	return $false
}

function Rotate-Shape {
	param($shape)
	$newShape = @()
	$rows = $shape.Shape.Length
	$cols = $shape.Shape[0].Length

	for ($i = 0; $i -lt $cols; $i++) {
		$newRow = @()
		for ($j = $rows - 1; $j -ge 0; $j--) {
			$newRow += $shape.Shape[$j][$i]
		}
		$newShape += ,$newRow
	}

	return @{
		Shape = $newShape
		X = $shape.X
		Y = $shape.Y
	}
}

function Draw-Field {
    $output = ""
    for ($y = 0; $y -lt $height; $y++) {
        $line = ""
        for ($x = 0; $x -lt $width; $x++) {
            $cell = $script:field[$y][$x]
            $isCurrent = $false
            
            if ($currentShape) {
                $sy = $y - $currentShape.Y
                $sx = $x - $currentShape.X
                if ($sy -ge 0 -and $sy -lt $currentShape.Shape.Length -and
                    $sx -ge 0 -and $sx -lt $currentShape.Shape[$sy].Length) {
                    $isCurrent = $currentShape.Shape[$sy][$sx] -ne 0
                }
            }
            
            if ($cell -ne 0 -or $isCurrent) {
                $line += "[]"
            } else {
                $line += "  "
            }
        }
        $output += $line + "`n"
    }

    [System.Console]::SetCursorPosition(0, 0)
    [System.Console]::Write($output)
    [System.Console]::WriteLine("Score: $score")

    $remainingLines = [Console]::WindowHeight - $height - 2
    if ($remainingLines -gt 0) {
        [System.Console]::WriteLine((" " * [Console]::WindowWidth) * $remainingLines)
        [System.Console]::SetCursorPosition(0, 0)
    }
}

$currentShape = Get-NewShape
$nextShape = Get-NewShape

while (-not $gameOver) {
	if ([Console]::KeyAvailable) {
		$key = $host.UI.RawUI.ReadKey("NoEcho,IncludeKeyDown")
		switch ($key.VirtualKeyCode) {
			37 {
				if (-not (Test-Collision $currentShape ($currentShape.X - 1) $currentShape.Y)) {
					$currentShape.X--
				}
			}
			39 {
				if (-not (Test-Collision $currentShape ($currentShape.X + 1) $currentShape.Y)) {
					$currentShape.X++
				}
			}
			38 {
				$rotated = Rotate-Shape $currentShape
				if (-not (Test-Collision $rotated $rotated.X $rotated.Y)) {
					$currentShape = $rotated
				}
			}
			40 {
				$fallInterval = 50
			}
		}
	}

	if (([DateTime]::Now - $lastUpdate).TotalMilliseconds -ge $fallInterval) {
		if (-not (Test-Collision $currentShape $currentShape.X ($currentShape.Y + 1))) {
			$currentShape.Y++
		} else {
			for ($i = 0; $i -lt $currentShape.Shape.Length; $i++) {
				for ($j = 0; $j -lt $currentShape.Shape[$i].Length; $j++) {
					if ($currentShape.Shape[$i][$j] -ne 0) {
						$y = $currentShape.Y + $i
						$x = $currentShape.X + $j
						if ($y -lt 0) { 
							$gameOver = $true
							break
						}
						$script:field[$y][$x] = 1
					}
				}
			}

			$lines = 0
			$currentY = $height - 1
			while ($currentY -ge 0) {
				$isFull = $true
				for ($xCheck = 0; $xCheck -lt $width; $xCheck++) {
					if ($script:field[$currentY][$xCheck] -eq 0) {
						$isFull = $false
						break
					}
				}

				if ($isFull) {
					$lines++
					for ($shiftY = $currentY; $shiftY -gt 0; $shiftY--) {
						for ($xCopy = 0; $xCopy -lt $width; $xCopy++) {
							$script:field[$shiftY][$xCopy] = $script:field[$shiftY - 1][$xCopy]
						}
					}
					for ($xClear = 0; $xClear -lt $width; $xClear++) {
						$script:field[0][$xClear] = 0
					}
				} else {
					$currentY--
				}
			}

			$score += switch ($lines) {
				1 { 40 }
				2 { 100 }
				3 { 300 }
				4 { 1200 }
				default { 0 }
			}

			$currentShape = $nextShape
			$nextShape = Get-NewShape

			if (Test-Collision $currentShape $currentShape.X $currentShape.Y) {
				$gameOver = $true
			}
		}
		$lastUpdate = [DateTime]::Now
		$fallInterval = 800
	}

	Draw-Field
	Start-Sleep -Milliseconds 20
}

Write-Host "Game Over! Final score: $score"