import Foundation
import Testing

@testable import WebsiteLibrary

@Suite(
    "Date+Stamps extension",
    .tags(.extensionTests)
)
struct DateStampsTests {

    // MARK: Methods tests

    @Test(arguments: zip(
        [0, -86_400, -172_800, -25_920_000] as [TimeInterval],
        ["today, 09:14", "yesterday, 09:14", "21 Sep, 09:14", "27 Nov 2025, 08:14"]
    ))
    func `stamps a date relative to today, on Amsterdam's clock`(
        offset: TimeInterval,
        expects stamp: String
    ) {
        #expect(Date.stub.addingTimeInterval(offset).stamp(relativeTo: .stub) == stamp)
    }

    @Test
    func `tells days apart at Amsterdam's midnight, not UTC's`() {
        // 23:30 and 01:00 in Amsterdam are 21:30 and 23:00 UTC: one day to UTC, two to Amsterdam.
        let lateEvening = Date.stub.addingTimeInterval(-35_040)
        let smallHours = Date.stub.addingTimeInterval(-29_640)

        #expect(lateEvening.stamp(relativeTo: smallHours) == "yesterday, 23:30")
    }

    @Test(arguments: zip(
        [171_000, 1_800, 180_000, 259_260] as [TimeInterval],
        ["47 h left", "under an hour left", "2 days left", "3 days left"]
    ))
    func `counts down in hours, then days`(
        interval: TimeInterval,
        expects countdown: String
    ) {
        #expect(Date.stub.addingTimeInterval(interval).countdown(from: .stub) == countdown)
    }

}