//
//  SceneGraphTests.swift
//  FirebladeECSTests
//
//  Created by Christian Treffs on 30.09.19.
//

import FirebladeECS
import XCTest

@available(*, deprecated, message: "This will be removed in the next minor update.")
class SceneGraphTests: XCTestCase {
    var nexus: Nexus!

    override func setUp() {
        super.setUp()
        nexus = Nexus()
    }

    override func tearDown() {
        super.tearDown()
        nexus = nil
    }

    func testAddChild() {
        let nttParrent = nexus.createEntity()
        let nttChild1 = nexus.createEntity()
        XCTAssertEqual(nttParrent.numChildren, 0)
        XCTAssertTrue(nttParrent.addChild(nttChild1))
        XCTAssertEqual(nttParrent.numChildren, 1)
        XCTAssertFalse(nttParrent.addChild(nttChild1))
        XCTAssertEqual(nttParrent.numChildren, 1)
    }

    func testRemoveChild() {
        let nttParrent = nexus.createEntity()
        let nttChild1 = nexus.createEntity()

        XCTAssertEqual(nttParrent.numChildren, 0)
        XCTAssertTrue(nttParrent.addChild(nttChild1))
        XCTAssertEqual(nttParrent.numChildren, 1)
        XCTAssertTrue(nttParrent.removeChild(nttChild1))
        XCTAssertEqual(nttParrent.numChildren, 0)
        XCTAssertFalse(nttParrent.removeChild(nttChild1))
        XCTAssertEqual(nttParrent.numChildren, 0)
        XCTAssertTrue(nttParrent.addChild(nttChild1))
        XCTAssertEqual(nttParrent.numChildren, 1)
    }

    func testRemoveAllChildren() {
        let nttParrent = nexus.createEntity()
        let nttChild1 = nexus.createEntity()
        let nttChild2 = nexus.createEntity()

        XCTAssertEqual(nttParrent.numChildren, 0)
        nttParrent.addChild(nttChild1)
        nttParrent.addChild(nttChild2)
        XCTAssertEqual(nttParrent.numChildren, 2)

        nttParrent.removeAllChildren()
        XCTAssertEqual(nttParrent.numChildren, 0)
    }

    func testDescendRelativesSimple() {
        let nttParrent = nexus.createEntity(with: Position(x: 1, y: 1))
        let child1Pos = Position(x: 2, y: 2)
        let nttChild1 = nexus.createEntity(with: child1Pos)

        nttParrent.addChild(nttChild1)

        let family = nexus.family(requires: Position.self)

        var counter: Int = 0

        XCTAssertEqual(child1Pos.x, 2)
        XCTAssertEqual(child1Pos.y, 2)

        family
            .descendRelatives(from: nttParrent)
            .forEach { (parent: Position, child: Position) in
                defer { counter += 1 }

                child.x += parent.x
                child.y += parent.y
        }

        XCTAssertEqual(counter, 1)
        XCTAssertEqual(child1Pos.x, 3)
        XCTAssertEqual(child1Pos.y, 3)
    }

    func testDescendRelativesOnlyFamilyMembers() {
        let otherComponents: [Component] = [Position(x: 0, y: 0), Velocity(a: 0), Party(partying: true), Color(), Name(name: "")]

        func addChild(to parent: Entity, index: Int) -> Entity {
            let randComp = otherComponents.randomElement()!
            let badChild = nexus.createEntity(with: randComp)
            let child = nexus.createEntity(with: Index(index: index))
            parent.addChild(child)
            parent.addChild(badChild)
            return child
        }

        let root = nexus.createEntity(with: Index(index: 0))

        var parent: Entity = root
        for i in 1..<10 {
            parent = addChild(to: parent, index: i)
        }

        XCTAssertEqual(nexus.numEntities, 19)

        var parentSum: Int = 0
        var childSum: Int = 0

        var lastIndex: Int = -1

        nexus
            .family(requires: Index.self)
            .descendRelatives(from: root)
            .forEach { (parent: Index, child: Index) in
                XCTAssertEqual(parent.index + 1, child.index)
                XCTAssertGreaterThan(parent.index, lastIndex)
                lastIndex = parent.index
                parentSum += parent.index
                childSum += child.index
        }

        XCTAssertEqual(parentSum, 36)
        XCTAssertEqual(childSum, 45)
    }
}