import XCTest
@testable import FocusFixer

final class WindowLocatorTests: XCTestCase {
    func testReturnsOwnerPIDWhenPointInsideWindow() {
        let windows = [
            WindowInfo(ownerPID: 111, layer: 0, bounds: CGRect(x: 0, y: 0, width: 100, height: 100))
        ]
        XCTAssertEqual(WindowLocator.ownerPID(at: CGPoint(x: 50, y: 50), in: windows), 111)
    }

    func testIgnoresNonZeroLayerWindows() {
        let windows = [
            WindowInfo(ownerPID: 999, layer: 25, bounds: CGRect(x: 0, y: 0, width: 100, height: 100))
        ]
        XCTAssertNil(WindowLocator.ownerPID(at: CGPoint(x: 50, y: 50), in: windows))
    }

    func testFallsThroughToNextWindowWhenTopWindowIsWrongLayer() {
        let windows = [
            WindowInfo(ownerPID: 1, layer: 25, bounds: CGRect(x: 0, y: 0, width: 100, height: 100)),
            WindowInfo(ownerPID: 2, layer: 0, bounds: CGRect(x: 0, y: 0, width: 100, height: 100))
        ]
        XCTAssertEqual(WindowLocator.ownerPID(at: CGPoint(x: 50, y: 50), in: windows), 2)
    }

    func testReturnsFrontmostWindowInZOrder() {
        // Overlapping layer-0 windows: front-to-back order (as returned by
        // CGWindowListCopyWindowInfo) determines which owner wins.
        let windows = [
            WindowInfo(ownerPID: 1, layer: 0, bounds: CGRect(x: 0, y: 0, width: 200, height: 200)),
            WindowInfo(ownerPID: 2, layer: 0, bounds: CGRect(x: 0, y: 0, width: 200, height: 200))
        ]
        XCTAssertEqual(WindowLocator.ownerPID(at: CGPoint(x: 50, y: 50), in: windows), 1)
    }

    func testEmptyWindowListReturnsNil() {
        XCTAssertNil(WindowLocator.ownerPID(at: CGPoint(x: 50, y: 50), in: []))
    }

    func testPointOutsideAllWindowsReturnsNil() {
        let windows = [
            WindowInfo(ownerPID: 1, layer: 0, bounds: CGRect(x: 0, y: 0, width: 100, height: 100))
        ]
        XCTAssertNil(WindowLocator.ownerPID(at: CGPoint(x: 500, y: 500), in: windows))
    }
}