import XCTest
@testable import MusicBridge

final class ProtocolTests: XCTestCase {
    private let fingerprint = String(repeating: "A", count: 64)

    func testPrivateAddresses() throws {
        for address in ["10.0.0.1", "172.16.0.1", "172.31.255.254", "192.168.1.10"] {
            XCTAssertTrue(Connection.isPrivateIPv4(address))
        }
        for address in ["127.0.0.1", "8.8.8.8", "172.32.0.1", "169.254.1.2", "192.168.1.999", "192.168.01.1", "localhost", "::1"] {
            XCTAssertFalse(Connection.isPrivateIPv4(address))
        }
    }

    func testRejectsCredentialOrPathInjection() {
        for address in ["http://192.168.1.2", "https://user@192.168.1.2", "https://192.168.1.2/path",
                        "https://192.168.1.2?token=secret", "https://192.168.1.2#fragment", "https://192.168.1.2:0"] {
            XCTAssertThrowsError(try Connection(endpoint: address, fingerprint: fingerprint))
        }
    }

    func testFingerprintValidation() throws {
        XCTAssertThrowsError(try Connection(endpoint: "https://192.168.1.2", fingerprint: String(repeating: "Z", count: 64)))
        XCTAssertThrowsError(try Connection(endpoint: "https://192.168.1.2", fingerprint: "AA"))
        XCTAssertEqual(try Connection(endpoint: "https://192.168.1.2:8765", fingerprint: fingerprint.lowercased()).fingerprint, fingerprint)
    }

    func testInvitationAndExpiry() throws {
        let now = Date(timeIntervalSince1970: 1_800_000_000)
        let payload: [String: Any] = ["version": 1, "endpoint": "https://192.168.1.10:8765",
                                      "certificateSha256": fingerprint, "code": "01234567",
                                      "expiresAt": ISO8601DateFormatter().string(from: now.addingTimeInterval(60))]
        let data = try JSONSerialization.data(withJSONObject: payload).base64EncodedString()
            .replacingOccurrences(of: "+", with: "-").replacingOccurrences(of: "/", with: "_").replacingOccurrences(of: "=", with: "")
        let text = "musicbridge://pair?data=\(data)"
        XCTAssertEqual(try Invitation.parse(text, now: now).code, "01234567")
        XCTAssertThrowsError(try Invitation.parse(text, now: now.addingTimeInterval(61)))
        XCTAssertThrowsError(try Invitation.parse(text + "&data=other", now: now))
    }

    func testCodeRequiresEightASCIIDigits() {
        XCTAssertTrue(Invitation.validCode("01234567"))
        XCTAssertFalse(Invitation.validCode("1234567"))
        XCTAssertFalse(Invitation.validCode("１２３４５６７８"))
    }

    func testWindowsInvitationTimestampAndMalformedJSON() throws {
        // System.Text.Json emits up to seven fractional digits and a numeric UTC offset.
        let json = """
        {"version":1,"endpoint":"https://192.168.1.23:8765","certificateSha256":"\(fingerprint)","code":"01234567","expiresAt":"2026-09-12T15:30:00.1234567+03:00"}
        """
        func payload(_ json: String) -> String {
            "musicbridge://pair?data=" + Data(json.utf8).base64EncodedString()
                .replacingOccurrences(of: "+", with: "-").replacingOccurrences(of: "/", with: "_").replacingOccurrences(of: "=", with: "")
        }
        let before = try XCTUnwrap(ISO8601DateFormatter().date(from: "2026-09-12T12:29:00Z"))
        XCTAssertEqual(try Invitation.parse(payload(json), now: before).code, "01234567")
        XCTAssertThrowsError(try Invitation.parse(payload(json), now: before.addingTimeInterval(120)))
        XCTAssertThrowsError(try Invitation.parse(payload("{}"), now: before)) { error in
            XCTAssertTrue(error is BridgeError)
        }
        XCTAssertThrowsError(try Invitation.parse("https://example.com"))
    }

    func testWindowsSnapshotAndTimeline() throws {
        let url = try XCTUnwrap(Bundle(for: Self.self).url(forResource: "state-v1", withExtension: "json"))
        let state = try JSONDecoder().decode(MediaState.self, from: Data(contentsOf: url))
        XCTAssertEqual(state.position(elapsed: 2), 44.5)
        XCTAssertEqual(state.position(elapsed: 9999), 180)
        XCTAssertTrue(state.capabilities.seek)
        XCTAssertEqual(state.volume, 0.5)
        XCTAssertNoThrow(try BridgeClient.validate(state))
    }

    func testCommandsCarryUniqueIDsAndOptionalValue() throws {
        let command = Command(type: "seek", value: 90.5)
        let object = try XCTUnwrap(JSONSerialization.jsonObject(with: JSONEncoder().encode(command)) as? [String: Any])
        XCTAssertEqual(object["type"] as? String, "seek")
        XCTAssertEqual(object["value"] as? Double, 90.5)
        XCTAssertNotEqual(command.id, Command(type: "seek", value: 90.5).id)
        let toggle = try XCTUnwrap(JSONSerialization.jsonObject(with: JSONEncoder().encode(Command(type: "toggle", value: nil))) as? [String: Any])
        XCTAssertNil(toggle["value"])
    }
}