// Copyright 2026 twonly contributors. BSD-style license; see LICENSE.

import AVFoundation
import XCTest

@testable import camera_avfoundation

final class CameraImageStreamScalerTests: XCTestCase {
  func testReducesBGRAFrameWithoutChangingPreviewBuffer() throws {
    var pixelBuffer: CVPixelBuffer?
    XCTAssertEqual(
      CVPixelBufferCreate(
        kCFAllocatorDefault, 1920, 1080, kCVPixelFormatType_32BGRA, nil, &pixelBuffer),
      kCVReturnSuccess)
    let buffer = try XCTUnwrap(pixelBuffer)
    CVPixelBufferLockBaseAddress(buffer, [])
    defer { CVPixelBufferUnlockBaseAddress(buffer, []) }
    let address = try XCTUnwrap(CVPixelBufferGetBaseAddress(buffer))
    memset(address, 127, CVPixelBufferGetBytesPerRow(buffer) * 1080)

    let plane = try XCTUnwrap(CameraImageStreamScaler.scaleBGRA(buffer, maximumDimension: 640))
    XCTAssertEqual(plane.width, 640)
    XCTAssertEqual(plane.height, 360)
    XCTAssertEqual(plane.bytesPerRow, 2560)
    XCTAssertEqual(plane.bytes.data.count, 640 * 360 * 4)
    XCTAssertEqual(plane.bytes.data.first, 127)
    XCTAssertEqual(CVPixelBufferGetWidth(buffer), 1920)
    XCTAssertEqual(CVPixelBufferGetHeight(buffer), 1080)
    XCTAssertEqual(address.load(as: UInt8.self), 127)
  }

  func testDoesNotUpscaleSmallFrames() throws {
    var pixelBuffer: CVPixelBuffer?
    XCTAssertEqual(
      CVPixelBufferCreate(
        kCFAllocatorDefault, 320, 240, kCVPixelFormatType_32BGRA, nil, &pixelBuffer),
      kCVReturnSuccess)
    let buffer = try XCTUnwrap(pixelBuffer)
    CVPixelBufferLockBaseAddress(buffer, [])
    defer { CVPixelBufferUnlockBaseAddress(buffer, []) }
    XCTAssertNil(CameraImageStreamScaler.scaleBGRA(buffer, maximumDimension: 640))
  }
}