/*

    Copyright (C) 2016 Apple Inc. All Rights Reserved.

    See LICENSE.txt for this sample’s licensing information

    Abstract:

    Tests to make sure that the `Dream` type correctly constructs a diff.

*/

import XCTest

class DreamDiffTests: XCTestCase {

    func testDiffingEqualDreams() {

        let dream1 = Dream(description: "foo", creature: .unicorn(.pink), effects: [.fireBreathing])

        let dream2 = Dream(description: "foo", creature: .unicorn(.pink), effects: [.fireBreathing])

        let diff = dream1.diffed(with: dream2)

        XCTAssertNil(diff.creatureChange)

        XCTAssertTrue(diff.insertedEffects.isEmpty)

        XCTAssertTrue(diff.removedEffects.isEmpty)

        XCTAssertNil(diff.descriptionChange)

        XCTAssertFalse(diff.hasChanges)

    }

    func testDiffsAreEqual() {

        let dream1 = Dream(description: "foo", creature: .unicorn(.pink), effects: [.fireBreathing])

        let dream2 = Dream(description: "bar", creature: .unicorn(.white), effects: [.laserFocus, .fireflies])

        let diff = dream1.diffed(with: dream2)

        XCTAssertEqual(diff,  diff)

    }

    func testDiffingDifferentDreams() {

        let dream1 = Dream(description: "foo", creature: .unicorn(.pink), effects: [.fireBreathing])

        let dream2 = Dream(description: "bar", creature: .unicorn(.white), effects: [.laserFocus, .fireflies])

        let diff = dream1.diffed(with: dream2)

        XCTAssertEqual(diff.descriptionChange?.from, "foo")

        XCTAssertEqual(diff.descriptionChange?.to, "bar")

        XCTAssertEqual(diff.creatureChange?.from, .unicorn(.pink))

        XCTAssertEqual(diff.creatureChange?.to, .unicorn(.white))

        XCTAssertEqual(diff.removedEffects, [.fireBreathing])

        XCTAssertEqual(diff.insertedEffects, [.laserFocus, .fireflies])

        XCTAssertTrue(diff.hasChanges)

    }

}