# frozen_string_literal: true

# Released under the MIT License.
# Copyright, 2019-2024, by Samuel Williams.

require "protocol/http2/headers_frame"

require "protocol/http2/connection_context"
require "protocol/http2/a_frame"

describe Protocol::HTTP2::HeadersFrame do
	let(:data) {"Hello World!"}
	let(:frame) {subject.new}
	
	it_behaves_like Protocol::HTTP2::AFrame do
		def before
			frame.set_flags(Protocol::HTTP2::END_HEADERS)
			frame.pack data
			
			super
		end
	end
	
	with "#pack" do
		it "adds appropriate padding" do
			frame.pack data
			
			expect(frame.length).to be == 12
			expect(frame).not.to be(:priority?)
		end
		
		it "ignores priority data" do
			frame.pack "xxxxx" + data
			frame.set_flags(Protocol::HTTP2::PRIORITY)
			
			expect(frame.length).to be == 17
			expect(frame).to be(:priority?)
			
			expect(frame.unpack).to be == data
		end
	end
	
	with "#unpack" do
		it "removes padding" do
			frame.pack data
			
			expect(frame.unpack).to be == data
		end
	end
	
	with "#continuation" do
		let(:stream) {StringIO.new}
		
		def before
			frame.pack "Hello World", maximum_size: 8
			
			super
		end
		
		it "generates chain of frames" do
			expect(frame).to be(:continued?)
			expect(frame.continuation).to be(:end_headers?)
			
			expect(frame.length).to be == 8
			expect(frame.continuation).not.to be_nil
			expect(frame.continuation.length).to be == 3
		end
		
		it "can read and write continuation frames" do
			frame.write(stream)
			stream.rewind
			
			frame2 = subject.new
			frame2.read(stream, 128)
			
			expect(frame).to be(:continued?)
			expect(frame.continuation).to be(:end_headers?)
			
			expect(frame.length).to be == 8
			expect(frame.continuation).not.to be_nil
			expect(frame.continuation.length).to be == 3
		end
		
		it "fails if the stream id of the continuation doesn't match" do
			frame.continuation.stream_id = frame.stream_id+1
			frame.write(stream)
			stream.rewind
			
			frame2 = subject.new
			expect do
				frame2.read(stream, 128)
			end.to raise_exception(Protocol::HTTP2::ProtocolError, message: be =~ /Invalid stream id/)
		end
		
		it "fails if the frame type of the continuation doesn't match" do
			frame.continuation.type = frame.type+1
			frame.write(stream)
			stream.rewind
			
			frame2 = subject.new
			expect do
				frame2.read(stream, 128)
			end.to raise_exception(Protocol::HTTP2::ProtocolError, message: be =~ /Invalid frame type/)
		end
	end
	
	with "client/server connection" do
		include_context Protocol::HTTP2::ConnectionContext
		
		def before
			client.open!
			server.open!
			
			# We force this to something low so we can exceed it without hitting the socket buffer:
			server.local_settings.current.instance_variable_set(:@maximum_frame_size, 128)
			
			super
		end
		
		let(:stream) {client.create_stream}
		
		it "rejects headers frame that exceeds maximum frame size" do
			frame.stream_id = stream.id
			frame.pack "\0" * (server.local_settings.maximum_frame_size + 1)
			
			client.write_frame(frame)
			
			expect do
				server.read_frame
			end.to raise_exception(Protocol::HTTP2::FrameSizeError)
			
			expect(client).to receive(:receive_goaway)
			
			expect do
				client.read_frame
			end.to raise_exception(Protocol::HTTP2::GoawayError)
		end
	end
	
	with "#inspect" do
		it "can generate a string representation" do
			expect(frame.inspect).to be =~ /Protocol::HTTP2::HeadersFrame stream_id=0 flags=0 0b/
		end
	end
end