import XCTest
@testable import CommandNotch

final class TerminalScrollCoordinatorTests: XCTestCase {
    func testScrollAwayFromBottomDisablesOutputFollow() {
        let coordinator = TerminalScrollCoordinator()

        coordinator.terminalDidScroll(to: 0.42, canScroll: true)

        XCTAssertFalse(coordinator.followsOutput)
        XCTAssertEqual(coordinator.outputRestorePosition(canScroll: true) ?? .nan, 0.42, accuracy: 0.0001)
    }

    func testTypingReEnablesFollowAndRequestsJumpToBottom() {
        let coordinator = TerminalScrollCoordinator()
        coordinator.terminalDidScroll(to: 0.42, canScroll: true)

        let shouldJump = coordinator.userDidStartTyping()

        XCTAssertTrue(shouldJump)
        XCTAssertTrue(coordinator.followsOutput)
        XCTAssertNil(coordinator.outputRestorePosition(canScroll: true))
    }

    func testScrollingBackToBottomReEnablesOutputFollow() {
        let coordinator = TerminalScrollCoordinator()
        coordinator.terminalDidScroll(to: 0.42, canScroll: true)

        coordinator.terminalDidScroll(to: 1, canScroll: true)

        XCTAssertTrue(coordinator.followsOutput)
        XCTAssertNil(coordinator.outputRestorePosition(canScroll: true))
    }

    func testSuppressedTrackingIgnoresProgrammaticScrollUpdates() {
        let coordinator = TerminalScrollCoordinator()
        coordinator.terminalDidScroll(to: 0.42, canScroll: true)

        coordinator.suppressTracking {
            coordinator.terminalDidScroll(to: 1, canScroll: true)
        }

        XCTAssertFalse(coordinator.followsOutput)
        XCTAssertEqual(coordinator.outputRestorePosition(canScroll: true) ?? .nan, 0.42, accuracy: 0.0001)
    }
}