/*
 * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
 * Copyright (c) 2023, Matthew Olsson <mattco@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <LibJS/Heap/GCPtr.h>
#include <LibWeb/Forward.h>
#include <LibWeb/WebIDL/ExceptionOr.h>
#include <LibWeb/WebIDL/Promise.h>

namespace Web::Streams {

using SizeAlgorithm = JS::SafeFunction<JS::Completion(JS::Value)>;
using PullAlgorithm = JS::SafeFunction<WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>>()>;
using CancelAlgorithm = JS::SafeFunction<WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>>(JS::Value)>;
using StartAlgorithm = JS::SafeFunction<WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>>()>;
using AbortAlgorithm = JS::SafeFunction<WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>>(JS::Value)>;
using CloseAlgorithm = JS::SafeFunction<WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>>()>;
using WriteAlgorithm = JS::SafeFunction<WebIDL::ExceptionOr<JS::GCPtr<WebIDL::Promise>>(JS::Value)>;

WebIDL::ExceptionOr<JS::NonnullGCPtr<ReadableStreamDefaultReader>> acquire_readable_stream_default_reader(ReadableStream&);
bool is_readable_stream_locked(ReadableStream const&);

void readable_stream_close(ReadableStream&);
void readable_stream_error(ReadableStream&, JS::Value error);
void readable_stream_add_read_request(ReadableStream&, ReadRequest const&);
WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> readable_stream_cancel(ReadableStream&, JS::Value reason);
void readable_stream_fulfill_read_request(ReadableStream&, JS::Value chunk, bool done);
size_t readable_stream_get_num_read_requests(ReadableStream&);
bool readable_stream_has_default_reader(ReadableStream&);

JS::NonnullGCPtr<WebIDL::Promise> readable_stream_reader_generic_cancel(ReadableStreamGenericReaderMixin&, JS::Value reason);
void readable_stream_reader_generic_initialize(ReadableStreamGenericReaderMixin&, ReadableStream&);
WebIDL::ExceptionOr<void> readable_stream_reader_generic_release(ReadableStreamGenericReaderMixin&);

void readable_stream_default_reader_error_read_requests(ReadableStreamDefaultReader&, JS::Value error);
void readable_stream_default_reader_read(ReadableStreamDefaultReader&, ReadRequest&);
WebIDL::ExceptionOr<void> readable_stream_default_reader_release(ReadableStreamDefaultReader&);
WebIDL::ExceptionOr<void> set_up_readable_stream_default_reader(ReadableStreamDefaultReader&, ReadableStream&);
void readable_stream_default_controller_close(ReadableStreamDefaultController&);
WebIDL::ExceptionOr<void> readable_stream_default_controller_enqueue(ReadableStreamDefaultController&, JS::Value chunk);
WebIDL::ExceptionOr<void> readable_stream_default_controller_can_pull_if_needed(ReadableStreamDefaultController&);
bool readable_stream_default_controller_should_call_pull(ReadableStreamDefaultController&);
void readable_stream_default_controller_clear_algorithms(ReadableStreamDefaultController&);

void readable_stream_default_controller_error(ReadableStreamDefaultController&, JS::Value error);
Optional<float> readable_stream_default_controller_get_desired_size(ReadableStreamDefaultController&);
bool readable_stream_default_controller_can_close_or_enqueue(ReadableStreamDefaultController&);
WebIDL::ExceptionOr<void> set_up_readable_stream_default_controller(ReadableStream&, ReadableStreamDefaultController&, StartAlgorithm&&, PullAlgorithm&&, CancelAlgorithm&&, double high_water_mark, SizeAlgorithm&&);
WebIDL::ExceptionOr<void> set_up_readable_stream_default_controller_from_underlying_source(ReadableStream&, JS::Value underlying_source_value, UnderlyingSource, double high_water_mark, SizeAlgorithm&&);

Optional<double> readable_byte_stream_controller_get_desired_size(ReadableByteStreamController const&);

WebIDL::ExceptionOr<JS::NonnullGCPtr<WritableStreamDefaultWriter>> acquire_writable_stream_default_writer(WritableStream&);
bool is_writable_stream_locked(WritableStream const&);
WebIDL::ExceptionOr<void> set_up_writable_stream_default_writer(WritableStreamDefaultWriter&, WritableStream&);
WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> writable_stream_abort(WritableStream&, JS::Value reason);
WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> writable_stream_close(WritableStream&);

WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> writable_stream_add_write_request(WritableStream&);
bool writable_stream_close_queued_or_in_flight(WritableStream const&);
WebIDL::ExceptionOr<void> writable_stream_deal_with_rejection(WritableStream&, JS::Value error);
WebIDL::ExceptionOr<void> writable_stream_finish_erroring(WritableStream&);
void writable_stream_finish_in_flight_close(WritableStream&);
WebIDL::ExceptionOr<void> writable_stream_finish_in_flight_close_with_error(WritableStream&, JS::Value error);
void writable_stream_finish_in_flight_write(WritableStream&);
WebIDL::ExceptionOr<void> writable_stream_finish_in_flight_write_with_error(WritableStream&, JS::Value error);
bool writable_stream_has_operation_marked_in_flight(WritableStream const&);
void writable_stream_mark_close_request_in_flight(WritableStream&);
void writable_stream_mark_first_write_request_in_flight(WritableStream&);
void writable_stream_reject_close_and_closed_promise_if_needed(WritableStream&);
WebIDL::ExceptionOr<void> writable_stream_start_erroring(WritableStream&, JS::Value reason);
void writable_stream_update_backpressure(WritableStream&, bool backpressure);

WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> writable_stream_default_writer_abort(WritableStreamDefaultWriter&, JS::Value reason);
WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> writable_stream_default_writer_close(WritableStreamDefaultWriter&);
void writable_stream_default_writer_ensure_closed_promise_rejected(WritableStreamDefaultWriter&, JS::Value error);
void writable_stream_default_writer_ensure_ready_promise_rejected(WritableStreamDefaultWriter&, JS::Value error);
Optional<double> writable_stream_default_writer_get_desired_size(WritableStreamDefaultWriter const&);
WebIDL::ExceptionOr<void> writable_stream_default_writer_release(WritableStreamDefaultWriter&);
WebIDL::ExceptionOr<JS::NonnullGCPtr<WebIDL::Promise>> writable_stream_default_writer_write(WritableStreamDefaultWriter&, JS::Value chunk);

WebIDL::ExceptionOr<void> set_up_writable_stream_default_controller(WritableStream&, WritableStreamDefaultController&, StartAlgorithm&&, WriteAlgorithm&&, CloseAlgorithm&&, AbortAlgorithm&&, double high_water_mark, SizeAlgorithm&&);
WebIDL::ExceptionOr<void> set_up_writable_stream_default_controller_from_underlying_sink(WritableStream&, JS::Value underlying_sink_value, UnderlyingSink&, double high_water_mark, SizeAlgorithm&& size_algorithm);
WebIDL::ExceptionOr<void> writable_stream_default_controller_advance_queue_if_needed(WritableStreamDefaultController&);
void writable_stream_default_controller_clear_algorithms(WritableStreamDefaultController&);
WebIDL::ExceptionOr<void> writable_stream_default_controller_close(WritableStreamDefaultController&);
WebIDL::ExceptionOr<void> writable_stream_default_controller_error(WritableStreamDefaultController&, JS::Value error);
WebIDL::ExceptionOr<void> writable_stream_default_controller_error_if_needed(WritableStreamDefaultController&, JS::Value error);
bool writable_stream_default_controller_get_backpressure(WritableStreamDefaultController const&);
WebIDL::ExceptionOr<JS::Value> writable_stream_default_controller_get_chunk_size(WritableStreamDefaultController&, JS::Value chunk);
double writable_stream_default_controller_get_desired_size(WritableStreamDefaultController const&);
WebIDL::ExceptionOr<void> writable_stream_default_controller_process_close(WritableStreamDefaultController&);
WebIDL::ExceptionOr<void> writable_stream_default_controller_process_write(WritableStreamDefaultController&, JS::Value chunk);
WebIDL::ExceptionOr<void> writable_stream_default_controller_write(WritableStreamDefaultController&, JS::Value chunk, JS::Value chunk_size);

bool is_non_negative_number(JS::Value);

JS::Value create_close_sentinel();
bool is_close_sentinel(JS::Value);
JS::ThrowCompletionOr<JS::Handle<WebIDL::CallbackType>> property_to_callback(JS::VM& vm, JS::Value value, JS::PropertyKey const& property_key);

// https://streams.spec.whatwg.org/#value-with-size
struct ValueWithSize {
    JS::Value value;
    double size;
};

// https://streams.spec.whatwg.org/#dequeue-value
template<typename T>
JS::Value dequeue_value(T& container)
{
    // 1. Assert: container has [[queue]] and [[queueTotalSize]] internal slots.

    // 2. Assert: container.[[queue]] is not empty.
    VERIFY(!container.queue().is_empty());

    // 3. Let valueWithSize be container.[[queue]][0].
    // 4. Remove valueWithSize from container.[[queue]].
    auto value_with_size = container.queue().take_first();

    // 5. Set container.[[queueTotalSize]] to container.[[queueTotalSize]] − valueWithSize’s size.
    container.set_queue_total_size(container.queue_total_size() - value_with_size.size);

    // 6. If container.[[queueTotalSize]] < 0, set container.[[queueTotalSize]] to 0. (This can occur due to rounding errors.)
    if (container.queue_total_size() < 0.0)
        container.set_queue_total_size(0.0);

    // 7. Return valueWithSize’s value.
    return value_with_size.value;
}

// https://streams.spec.whatwg.org/#enqueue-value-with-size
template<typename T>
WebIDL::ExceptionOr<void> enqueue_value_with_size(T& container, JS::Value value, JS::Value size_value)
{
    // 1. Assert: container has [[queue]] and [[queueTotalSize]] internal slots.

    // 2. If ! IsNonNegativeNumber(size) is false, throw a RangeError exception.
    if (!is_non_negative_number(size_value))
        return WebIDL::SimpleException { WebIDL::SimpleExceptionType::RangeError, "Chunk has non-positive size"sv };

    auto size = size_value.as_double();

    // 3. If size is +∞, throw a RangeError exception.
    if (size == HUGE_VAL)
        return WebIDL::SimpleException { WebIDL::SimpleExceptionType::RangeError, "Chunk has infinite size"sv };

    // 4. Append a new value-with-size with value value and size size to container.[[queue]].
    container.queue().append({ value, size });

    // 5. Set container.[[queueTotalSize]] to container.[[queueTotalSize]] + size.
    container.set_queue_total_size(container.queue_total_size() + size);

    return {};
}

// https://streams.spec.whatwg.org/#peek-queue-value
template<typename T>
JS::Value peek_queue_value(T& container)
{
    // 1. Assert: container has [[queue]] and [[queueTotalSize]] internal slots.

    // 2. Assert: container.[[queue]] is not empty.
    VERIFY(!container.queue().is_empty());

    // 3. Let valueWithSize be container.[[queue]][0].
    auto& value_with_size = container.queue().first();

    // 4. Return valueWithSize’s value.
    return value_with_size.value;
}

// https://streams.spec.whatwg.org/#reset-queue
template<typename T>
void reset_queue(T& container)
{
    // 1. Assert: container has [[queue]] and [[queueTotalSize]] internal slots.

    // 2. Set container.[[queue]] to a new empty list.
    container.queue().clear();

    // 3. Set container.[[queueTotalSize]] to 0.
    container.set_queue_total_size(0);
}

}