import { cleanup, fireEvent, render, screen, waitFor } from '@testing-library/svelte';
import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest';
import { createMessageEnvelope } from '@vela/protocol';
import VoiceSessionShell from '../src/lib/VoiceSessionShell.svelte';

class MockWebSocket {
	static CONNECTING = 0;
	static OPEN = 1;
	static CLOSING = 2;
	static CLOSED = 3;
	static instances = [];

	constructor(url) {
		this.url = url;
		this.readyState = MockWebSocket.CONNECTING;
		this.sent = [];
		this.onopen = null;
		this.onmessage = null;
		this.onerror = null;
		this.onclose = null;
		MockWebSocket.instances.push(this);
	}

	send(message) {
		this.sent.push(message);
	}

	open() {
		this.readyState = MockWebSocket.OPEN;
		this.onopen?.();
	}

	message(payload) {
		this.onmessage?.({ data: JSON.stringify(payload) });
	}

	close(code = 1000, reason = 'client disconnect', wasClean = true) {
		this.readyState = MockWebSocket.CLOSED;
		this.onclose?.({ code, reason, wasClean });
	}

	static latest() {
		return MockWebSocket.instances.at(-1);
	}

	static reset() {
		MockWebSocket.instances = [];
	}
}

function getByTestId(id) {
	return screen.getByTestId(id);
}

describe('voice session shell', () => {
	beforeEach(() => {
		MockWebSocket.reset();
		vi.stubGlobal('WebSocket', MockWebSocket);
	});

	afterEach(() => {
		cleanup();
		vi.unstubAllGlobals();
	});

	it('keeps mocked turn unavailable while disconnected and after disconnect', async () => {
		render(VoiceSessionShell);

		expect(getByTestId('connection-state').textContent).toBe('not connected');
		expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(true);
		expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(true);

		await fireEvent.click(getByTestId('connect-button'));
		const socket = MockWebSocket.latest();
		socket.open();
		socket.message(createMessageEnvelope('session.ready', { sessionId: 'session-123' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('connection-state').textContent).toBe('connected');
			expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(false);
			expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(false);
		});

		await fireEvent.click(getByTestId('disconnect-button'));
		socket.close(1000, 'client disconnect', true);

		await waitFor(() => {
			expect(getByTestId('connection-state').textContent).toBe('disconnected');
			expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(true);
			expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(true);
			expect(getByTestId('session-id').textContent).toBe('session-123');
		});
	});

	it('runs a placeholder mic-control cycle, streams mocked assistant text, and keeps mocked turn usable on the same socket', async () => {
		render(VoiceSessionShell);

		await fireEvent.click(getByTestId('connect-button'));
		const socket = MockWebSocket.latest();
		socket.open();

		await waitFor(() => {
			expect(getByTestId('connection-state').textContent).toBe('connected');
		});

		expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(true);

		socket.message(createMessageEnvelope('session.ready', { sessionId: 'session-mic' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(false);
		});

		await fireEvent.mouseDown(getByTestId('mic-control-button'));

		expect(socket.sent).toHaveLength(1);
		expect(JSON.parse(socket.sent[0])).toEqual({
			type: 'input_audio.append',
			payload: { chunk: 'placeholder-control-shell-chunk' }
		});
		expect(getByTestId('mic-control-status').textContent).toBe('holding');

		socket.message(createMessageEnvelope('session.state', { value: 'listening' }));
		socket.message(
			createMessageEnvelope('transcript.partial', {
				text: '[mocked partial] Placeholder push-to-talk transcript in progress.'
			})
		);

		await waitFor(() => {
			expect(getByTestId('gateway-session-state').textContent).toBe('listening');
			expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(true);
			expect(getByTestId('user-transcript').textContent).toBe(
				'[mocked partial] Placeholder push-to-talk transcript in progress.'
			);
			expect(getByTestId('partial-transcript').textContent).toBe(
				'[mocked partial] Placeholder push-to-talk transcript in progress.'
			);
		});

		await fireEvent.mouseUp(getByTestId('mic-control-button'));

		expect(socket.sent).toHaveLength(2);
		expect(JSON.parse(socket.sent[1])).toEqual({
			type: 'input_audio.commit',
			payload: {}
		});
		expect(getByTestId('mic-control-status').textContent).toBe('idle');

		socket.message(
			createMessageEnvelope('transcript.final', {
				text: '[mocked final] Placeholder push-to-talk transcript completed from 1 appended chunk.'
			})
		);
		socket.message(createMessageEnvelope('session.state', { value: 'thinking' }));
		socket.message(createMessageEnvelope('session.state', { value: 'speaking' }));
		socket.message(createMessageEnvelope('response.text.delta', { text: '[mocked assistant] ' }));
		socket.message(
			createMessageEnvelope('response.text.delta', {
				text: 'This is a deterministic mocked response from the gateway vertical slice.'
			})
		);
		socket.message(createMessageEnvelope('response.completed', {}));

		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('gateway-session-state').textContent).toBe('idle');
			expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(false);
			expect(getByTestId('user-transcript').textContent).toBe(
				'[mocked final] Placeholder push-to-talk transcript completed from 1 appended chunk.'
			);
			expect(getByTestId('assistant-response').textContent).toBe(
				'[mocked assistant] This is a deterministic mocked response from the gateway vertical slice.'
			);
			expect(getByTestId('partial-transcript').textContent).toBe('none');
		});

		await fireEvent.click(getByTestId('mocked-turn-button'));

		expect(socket.sent).toHaveLength(3);
		expect(JSON.parse(socket.sent[2]).type).toBe('mocked.turn.trigger');
	});

	it('keeps rendered push-to-talk transcript and assistant text visible after cancel', async () => {
		render(VoiceSessionShell);

		await fireEvent.click(getByTestId('connect-button'));
		const socket = MockWebSocket.latest();
		socket.open();
		socket.message(createMessageEnvelope('session.ready', { sessionId: 'session-ptt-cancel' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(false);
		});

		await fireEvent.mouseDown(getByTestId('mic-control-button'));
		socket.message(createMessageEnvelope('session.state', { value: 'listening' }));
		socket.message(
			createMessageEnvelope('transcript.partial', {
				text: '[mocked partial] Placeholder push-to-talk transcript in progress.'
			})
		);

		await fireEvent.mouseUp(getByTestId('mic-control-button'));
		expect(JSON.parse(socket.sent[1]).type).toBe('input_audio.commit');

		socket.message(
			createMessageEnvelope('transcript.final', {
				text: '[mocked final] Placeholder push-to-talk transcript completed from 1 appended chunk.'
			})
		);
		socket.message(createMessageEnvelope('session.state', { value: 'thinking' }));
		socket.message(createMessageEnvelope('session.state', { value: 'speaking' }));
		socket.message(createMessageEnvelope('response.text.delta', { text: '[mocked assistant] ' }));

		await waitFor(() => {
			expect(getByTestId('cancel-turn-button').hasAttribute('disabled')).toBe(false);
			expect(getByTestId('assistant-response').textContent).toBe('[mocked assistant] ');
		});

		await fireEvent.click(getByTestId('cancel-turn-button'));
		expect(JSON.parse(socket.sent[2]).type).toBe('response.cancel');

		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('gateway-session-state').textContent).toBe('idle');
			expect(getByTestId('mocked-turn-status').textContent).toBe('idle');
			expect(getByTestId('cancel-turn-button').hasAttribute('disabled')).toBe(true);
			expect(getByTestId('user-transcript').textContent).toBe(
				'[mocked final] Placeholder push-to-talk transcript completed from 1 appended chunk.'
			);
			expect(getByTestId('assistant-response').textContent).toBe('[mocked assistant] ');
			expect(getByTestId('mic-control-button').hasAttribute('disabled')).toBe(false);
		});
	});

	it('renders mocked transcript before assistant response for a connected session', async () => {
		render(VoiceSessionShell);

		await fireEvent.click(getByTestId('connect-button'));
		const socket = MockWebSocket.latest();
		socket.open();
		socket.message(createMessageEnvelope('session.ready', { sessionId: 'session-456' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('connection-state').textContent).toBe('connected');
		});

		await fireEvent.click(getByTestId('mocked-turn-button'));

		expect(socket.sent).toHaveLength(1);
		const sentMessage = JSON.parse(socket.sent[0]);
		expect(sentMessage.type).toBe('mocked.turn.trigger');

		socket.message(createMessageEnvelope('session.state', { value: 'listening' }));
		socket.message(
			createMessageEnvelope('transcript.partial', {
				text: '[mocked partial] Placeholder push-to-talk transcript in progress.'
			})
		);
		socket.message(createMessageEnvelope('transcript.final', { text: 'Turn on the office lamp.' }));
		socket.message(createMessageEnvelope('session.state', { value: 'thinking' }));
		socket.message(createMessageEnvelope('session.state', { value: 'speaking' }));
		socket.message(createMessageEnvelope('response.text.delta', { text: 'Mocked ' }));
		socket.message(createMessageEnvelope('response.text.delta', { text: 'assistant response.' }));
		socket.message(createMessageEnvelope('response.completed', { reason: 'mocked_turn_complete' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('user-transcript').textContent).toBe('Turn on the office lamp.');
			expect(getByTestId('partial-transcript').textContent).toBe('none');
			expect(getByTestId('assistant-response').textContent).toBe('Mocked assistant response.');
			expect(getByTestId('conversation-render-order').textContent).toBe('transcript>response');
			expect(getByTestId('gateway-session-state').textContent).toBe('idle');
		});
	});

	it('blocks mocked turn trigger before session.ready and allows it after session.ready', async () => {
		render(VoiceSessionShell);

		await fireEvent.click(getByTestId('connect-button'));
		const socket = MockWebSocket.latest();
		socket.open();

		await waitFor(() => {
			expect(getByTestId('connection-state').textContent).toBe('connected');
		});

		expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(true);
		await fireEvent.click(getByTestId('mocked-turn-button'));
		expect(socket.sent).toHaveLength(0);
		expect(getByTestId('last-error').textContent).toBe('mocked turn requires session.ready');

		socket.message(createMessageEnvelope('session.ready', { sessionId: 'session-789' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(false);
		});

		await fireEvent.click(getByTestId('mocked-turn-button'));

		expect(socket.sent).toHaveLength(1);
		expect(JSON.parse(socket.sent[0]).type).toBe('mocked.turn.trigger');
	});

	it('shows cancel control during an active mocked turn and preserves rendered text after cancel', async () => {
		render(VoiceSessionShell);

		await fireEvent.click(getByTestId('connect-button'));
		const socket = MockWebSocket.latest();
		socket.open();
		socket.message(createMessageEnvelope('session.ready', { sessionId: 'session-cancel' }));
		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('cancel-turn-button').hasAttribute('disabled')).toBe(true);
		});

		await fireEvent.click(getByTestId('mocked-turn-button'));

		expect(JSON.parse(socket.sent[0]).type).toBe('mocked.turn.trigger');

		socket.message(createMessageEnvelope('session.state', { value: 'listening' }));
		socket.message(createMessageEnvelope('transcript.final', { text: 'Keep this transcript.' }));
		socket.message(createMessageEnvelope('session.state', { value: 'thinking' }));
		socket.message(createMessageEnvelope('session.state', { value: 'speaking' }));
		socket.message(createMessageEnvelope('response.text.delta', { text: 'Partial response' }));

		await waitFor(() => {
			expect(getByTestId('cancel-turn-button').hasAttribute('disabled')).toBe(false);
			expect(getByTestId('assistant-response').textContent).toBe('Partial response');
		});

		await fireEvent.click(getByTestId('cancel-turn-button'));

		expect(JSON.parse(socket.sent[1]).type).toBe('response.cancel');

		socket.message(createMessageEnvelope('session.state', { value: 'idle' }));

		await waitFor(() => {
			expect(getByTestId('mocked-turn-status').textContent).toBe('idle');
			expect(getByTestId('gateway-session-state').textContent).toBe('idle');
			expect(getByTestId('cancel-turn-button').hasAttribute('disabled')).toBe(true);
			expect(getByTestId('mocked-turn-button').hasAttribute('disabled')).toBe(false);
			expect(getByTestId('user-transcript').textContent).toBe('Keep this transcript.');
			expect(getByTestId('assistant-response').textContent).toBe('Partial response');
		});
	});
});