import Foundation
import Testing

@testable import Persistence

@Suite(
    "Sale model",
    .tags(.model)
)
struct SaleTests {

    // MARK: Computed tests

    @Test
    func `walks the handshake one step at a time`() {
        #expect(sale().completed == .agreed)
        #expect(sale().next == .paid)
        #expect(sale(paid: true).completed == .paid)
        #expect(sale(paid: true, sent: true).completed == .sent)
        #expect(sale(paid: true, sent: true, received: true).completed == .received)
        #expect(sale(paid: true, sent: true, received: true, buyerRating: 5).completed == .received)
        #expect(sale(paid: true, sent: true, received: true, buyerRating: 5, sellerRating: 4).completed == .rated)
        #expect(sale(paid: true, sent: true, received: true, buyerRating: 5, sellerRating: 4).next == nil)
    }

    @Test
    func `adds the shipping to the price`() {
        #expect(sale().totalCents == 22_100)
    }

    // MARK: Methods tests

    @Test
    func `gives each step to its party, once, in order`() {
        #expect(sale().allows(.markPaid(note: ""), by: .buyer))
        #expect(!sale().allows(.markPaid(note: ""), by: .seller))
        #expect(!sale(paid: true).allows(.markPaid(note: ""), by: .buyer))

        #expect(!sale().allows(.markSent(note: ""), by: .seller))
        #expect(sale(paid: true).allows(.markSent(note: ""), by: .seller))
        #expect(!sale(paid: true).allows(.markSent(note: ""), by: .buyer))

        #expect(!sale(paid: true).allows(.markReceived, by: .buyer))
        #expect(sale(paid: true, sent: true).allows(.markReceived, by: .buyer))
        #expect(!sale(paid: true, sent: true).allows(.markReceived, by: .seller))
    }

    @Test
    func `unlocks ratings only once the copy is received, one per party, out of five`() {
        let received = sale(paid: true, sent: true, received: true)

        #expect(!sale(paid: true, sent: true).allows(.rate(stars: 5), by: .buyer))
        #expect(received.allows(.rate(stars: 5), by: .buyer))
        #expect(received.allows(.rate(stars: 1), by: .seller))
        #expect(!received.allows(.rate(stars: 0), by: .buyer))
        #expect(!received.allows(.rate(stars: 6), by: .buyer))
        #expect(!sale(paid: true, sent: true, received: true, buyerRating: 5).allows(.rate(stars: 4), by: .buyer))
        #expect(sale(paid: true, sent: true, received: true, buyerRating: 5).allows(.rate(stars: 4), by: .seller))
    }

    @Test
    func `knows its parties`() {
        let sale = sale()

        #expect(sale.role(of: sale.buyer.id) == .buyer)
        #expect(sale.role(of: sale.seller.id) == .seller)
        #expect(sale.role(of: .init()) == nil)
    }

    // MARK: Offer tests

    @Test(arguments: zip(
        [24_000, 1_400, 4_500, 100],
        [19_200, 1_200, 3_600, 100]
    ))
    func `floors offers at four fifths of the asking price, in whole euros`(
        asking: Int,
        expects floor: Int
    ) {
        #expect(Offer.floor(forAsking: asking) == floor)
    }

}

// MARK: - Helpers

private extension SaleTests {

    /// A sale of the first demo listing at €215 + €6, as far along as told.
    func sale(
        paid: Bool = false,
        sent: Bool = false,
        received: Bool = false,
        buyerRating: Int? = nil,
        sellerRating: Int? = nil
    ) -> Sale {
        let stamp = Date(timeIntervalSince1970: 0)

        return .init(
            number: 48_213,
            conversationID: .init(),
            listing: Seed.listings[0],
            buyer: .init(id: .init(), email: "mara.v@example.com", displayName: "Mara Visser"),
            seller: .init(id: .init(), email: "joost@kestrelrow.example", displayName: "Joost de Wit"),
            priceCents: 21_500,
            askedCents: 24_000,
            shippingCents: 600,
            declared: .init(grade: "CGC 9.8", pageQuality: "White", printing: "First printing", notes: ""),
            agreedAt: stamp,
            paidAt: paid ? stamp : nil,
            sentAt: sent ? stamp : nil,
            receivedAt: received ? stamp : nil,
            buyerRating: buyerRating,
            sellerRating: sellerRating
        )
    }

}