import XCTest
@testable import LChatCore

// Pure-rule twins of web/static/ui.js displayNameFor / renameNotice (#577) —
// the same cases test/ui.test.mjs pins on the web side, so the two
// implementations can't drift apart.
final class NicknamesTests: XCTestCase {
    func testDisplayNameMyNameWins() {
        XCTAssertEqual(Nicknames.displayName(.init(name: "Dermo", seen: "Dermo"), label: "Dermot"), "Dermo")
        XCTAssertEqual(Nicknames.displayName(nil, label: "Dermot"), "Dermot")
        XCTAssertEqual(Nicknames.displayName(nil, label: nil), "")
        // Empty nickname = no nickname.
        XCTAssertEqual(Nicknames.displayName(.init(name: "", seen: ""), label: "Dermot"), "Dermot")
    }

    func testRenameNoticeFiresOncePerUnacknowledgedRename() {
        // The #577 scenario: invited as Dermo, renames to Dermot → the choice.
        let fresh = Nicknames.renameNotice(.init(name: "Dermo", seen: "Dermo"), label: "Dermot")
        XCTAssertEqual(fresh?.from, "Dermo")
        XCTAssertEqual(fresh?.to, "Dermot")
        // Acknowledged (kept my name): seen catches up, no more prompting.
        XCTAssertNil(Nicknames.renameNotice(.init(name: "Dermo", seen: "Dermot"), label: "Dermot"))
        // …until they rename AGAIN.
        let again = Nicknames.renameNotice(.init(name: "Dermo", seen: "Dermot"), label: "Diarmuid")
        XCTAssertEqual(again?.to, "Diarmuid")
        // They renamed to exactly what I call them — nothing to ask.
        XCTAssertNil(Nicknames.renameNotice(.init(name: "Dermo", seen: "x"), label: "Dermo"))
        // No nickname / no published name yet → never a notice.
        XCTAssertNil(Nicknames.renameNotice(nil, label: "Dermot"))
        XCTAssertNil(Nicknames.renameNotice(.init(name: "Dermo", seen: "Dermo"), label: ""))
    }
}