import XCTest
@testable import RastrilloApple

final class StreamLinesTests: XCTestCase {
  func testUTF8AndAllSSELineEndings() throws {
    var parser = NativeStreamLines()
    let input = "\u{FEFF}event: update\r\ndata: café 👩🏽‍💻\r\r: ping\n\n"
    let lines = try input.utf8.compactMap { try parser.append($0) }
    XCTAssertEqual(lines, ["event: update", "data: café 👩🏽‍💻", "", ": ping", ""])
  }

  func testInvalidUTF8DoesNotReachConsumer() throws {
    var parser = NativeStreamLines()
    XCTAssertNil(try parser.append(0xff))
    XCTAssertThrowsError(try parser.append(10))
  }

  func testLineLimitRejectsBeforeUnboundedAllocation() throws {
    var parser = NativeStreamLines(lineLimit: 4)
    for byte in "data".utf8 { XCTAssertNil(try parser.append(byte)) }
    XCTAssertThrowsError(try parser.append(58))
  }

  func testEventLimitSpansLinesAndResetsAtDelimiter() throws {
    var parser = NativeStreamLines(lineLimit: 8, eventLimit: 8)
    _ = try "1234\n5678\n".utf8.compactMap { try parser.append($0) }
    XCTAssertThrowsError(try parser.append(57))
    XCTAssertEqual(try parser.append(10), "")
    XCTAssertNil(try parser.append(57))
  }

  func testUnterminatedLineIsNotDelivered() throws {
    var parser = NativeStreamLines()
    XCTAssertEqual(try "event: update\ndata: partial".utf8.compactMap { try parser.append($0) }, ["event: update"])
  }
}