import XCTest
@testable import MyPassCore

final class TOTPGeneratorTests: XCTestCase {
    // RFC 6238 Section 8 test vectors for SHA-1
    // secret = "12345678901234567890" (ASCII), base32 = "GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ"
    let sha1Secret = "GEZDGNBVGY3TQOJQGEZDGNBVGY3TQOJQ"

    func test_sha1_at59s() {
        let config = TOTPConfig(secret: sha1Secret, period: 30, digits: 8, algorithm: .sha1)
        let date = Date(timeIntervalSince1970: 59)
        XCTAssertEqual(TOTPGenerator.generate(config: config, at: date), "94287082")
    }

    func test_sha1_at1111111109s() {
        let config = TOTPConfig(secret: sha1Secret, period: 30, digits: 8, algorithm: .sha1)
        let date = Date(timeIntervalSince1970: 1111111109)
        XCTAssertEqual(TOTPGenerator.generate(config: config, at: date), "07081804")
    }

    func test_secondsRemaining_isWithinPeriod() {
        let config = TOTPConfig(secret: sha1Secret, period: 30)
        let remaining = TOTPGenerator.secondsRemaining(config: config, at: Date())
        XCTAssertGreaterThan(remaining, 0)
        XCTAssertLessThanOrEqual(remaining, 30)
    }

    func test_generate_defaultSixDigits() {
        let config = TOTPConfig(secret: sha1Secret)
        let code = TOTPGenerator.generate(config: config, at: Date())
        XCTAssertEqual(code.count, 6)
        XCTAssertNotNil(Int(code))
    }
}