/*
 * Copyright 2024 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#pragma once

#include <perfetto/config/android/android_input_event_config.pbzero.h>
#include <perfetto/trace/android/android_input_event.pbzero.h>
#include <perfetto/trace/evdev.pbzero.h>

#include "InputTracingBackendInterface.h"
#include "InputTracingPerfettoBackendConfig.h"
#include "reader/include/RawEvent.h"

namespace proto = perfetto::protos::pbzero;

namespace android::input_trace {

namespace internal {

using namespace ftl::flag_operators;

// The trace config to use for maximal tracing.
const impl::TraceConfig CONFIG_TRACE_ALL{
        .flags = impl::TraceFlag::TRACE_DISPATCHER_INPUT_EVENTS |
                impl::TraceFlag::TRACE_DISPATCHER_WINDOW_DISPATCH,
        .rules = {impl::TraceRule{.level = impl::TraceLevel::TRACE_LEVEL_COMPLETE,
                                  .matchAllPackages = {},
                                  .matchAnyPackages = {},
                                  .matchSecure{},
                                  .matchImeConnectionActive = {}}},
};

template <typename Pointer>
void writeAxisValue(Pointer* pointer, int32_t axis, float value, bool isRedacted) {
    auto* axisEntry = pointer->add_axis_value();
    axisEntry->set_axis(axis);

    if (!isRedacted) {
        axisEntry->set_value(value);
    }
}

} // namespace internal

/**
 * Write traced events into Perfetto protos.
 *
 * This class is templated so that the logic can be tested while substituting the proto classes
 * auto-generated by Perfetto's pbzero library with mock implementations.
 */
template <typename ProtoMotion, typename ProtoKey, typename ProtoDispatch, typename ProtoEvdev,
          typename ProtoConfigDecoder>
class AndroidInputEventProtoConverter {
public:
    static void toProtoMotionEvent(const TracedMotionEvent& event, ProtoMotion& outProto,
                                   bool isRedacted) {
        outProto.set_event_id(event.id);
        outProto.set_event_time_nanos(event.eventTime);
        outProto.set_down_time_nanos(event.downTime);
        outProto.set_source(event.source);
        outProto.set_action(event.action);
        outProto.set_device_id(event.deviceId);
        outProto.set_display_id(event.displayId.val());
        outProto.set_classification(static_cast<int32_t>(event.classification));
        outProto.set_flags(event.flags.get());
        outProto.set_policy_flags(event.policyFlags);
        outProto.set_button_state(event.buttonState);
        outProto.set_action_button(event.actionButton);

        if (!isRedacted) {
            outProto.set_cursor_position_x(event.xCursorPosition);
            outProto.set_cursor_position_y(event.yCursorPosition);
            outProto.set_meta_state(event.metaState);
            outProto.set_precision_x(event.xPrecision);
            outProto.set_precision_y(event.yPrecision);
        }

        for (uint32_t i = 0; i < event.pointerProperties.size(); i++) {
            auto* pointer = outProto.add_pointer();

            const auto& props = event.pointerProperties[i];
            pointer->set_pointer_id(props.id);
            pointer->set_tool_type(static_cast<int32_t>(props.toolType));

            const auto& coords = event.pointerCoords[i];
            auto bits = BitSet64(coords.bits);

            if (isFromSource(event.source, AINPUT_SOURCE_CLASS_POINTER)) {
                // Always include the X and Y axes for pointer events, since the
                // bits will not be marked if the value is 0.
                for (const auto axis : {AMOTION_EVENT_AXIS_X, AMOTION_EVENT_AXIS_Y}) {
                    if (!bits.hasBit(axis)) {
                        internal::writeAxisValue(pointer, axis, 0.0f, isRedacted);
                    }
                }
            }

            for (int32_t axisIndex = 0; !bits.isEmpty(); axisIndex++) {
                const auto axis = bits.clearFirstMarkedBit();
                internal::writeAxisValue(pointer, axis, coords.values[axisIndex], isRedacted);
            }
        }
    }

    static void toProtoKeyEvent(const TracedKeyEvent& event, ProtoKey& outProto, bool isRedacted) {
        outProto.set_event_id(event.id);
        outProto.set_event_time_nanos(event.eventTime);
        outProto.set_down_time_nanos(event.downTime);
        outProto.set_source(event.source);
        outProto.set_action(event.action);
        outProto.set_device_id(event.deviceId);
        outProto.set_display_id(event.displayId.val());
        outProto.set_repeat_count(event.repeatCount);
        outProto.set_flags(event.flags);
        outProto.set_policy_flags(event.policyFlags);

        if (!isRedacted) {
            outProto.set_key_code(event.keyCode);
            outProto.set_scan_code(event.scanCode);
            outProto.set_meta_state(event.metaState);
        }
    }

    static void toProtoWindowDispatchEvent(const WindowDispatchArgs& args, ProtoDispatch& outProto,
                                           bool isRedacted) {
        std::visit([&](auto entry) { outProto.set_event_id(entry.id); }, args.eventEntry);
        outProto.set_vsync_id(args.vsyncId);
        outProto.set_window_id(args.windowId);
        outProto.set_resolved_flags(args.resolvedMotionFlags.get());

        if (isRedacted) {
            return;
        }
        if (auto* motion = std::get_if<TracedMotionEvent>(&args.eventEntry); motion != nullptr) {
            for (size_t i = 0; i < motion->pointerProperties.size(); i++) {
                auto* pointerProto = outProto.add_dispatched_pointer();
                pointerProto->set_pointer_id(motion->pointerProperties[i].id);
                const auto& coords = motion->pointerCoords[i];
                const auto rawXY =
                        MotionEvent::calculateTransformedXY(motion->source, args.rawTransform,
                                                            coords.getXYValue());
                if (coords.getXYValue() != rawXY) {
                    // These values are only traced if they were modified by the raw transform
                    // to save space. Trace consumers should be aware of this optimization.
                    pointerProto->set_x_in_display(rawXY.x);
                    pointerProto->set_y_in_display(rawXY.y);
                }

                const auto coordsInWindow =
                        MotionEvent::calculateTransformedCoords(motion->source, motion->flags,
                                                                args.transform, coords);
                auto bits = BitSet64(coords.bits);
                for (int32_t axisIndex = 0; !bits.isEmpty(); axisIndex++) {
                    const uint32_t axis = bits.clearFirstMarkedBit();
                    const float axisValueInWindow = coordsInWindow.values[axisIndex];
                    // Only values that are modified by the window transform are traced.
                    if (coords.values[axisIndex] != axisValueInWindow) {
                        auto* axisEntry = pointerProto->add_axis_value_in_window();
                        axisEntry->set_axis(axis);
                        axisEntry->set_value(axisValueInWindow);
                    }
                }
            }
        }
    }

    static void toProtoEvdevEvent(const RawEvent& rawEvent, ProtoEvdev& outProto) {
        outProto.set_device_id(rawEvent.deviceId);
        auto* inputEvent = outProto.set_input_event();
        // TODO(b/394861376): only set the kernel timestamp when it's changed since the last one, to
        // reduce trace size.
        inputEvent->set_kernel_timestamp(rawEvent.when);
        inputEvent->set_type(rawEvent.type);
        inputEvent->set_code(rawEvent.code);
        inputEvent->set_value(rawEvent.value);
    }

    static impl::TraceConfig parseConfig(ProtoConfigDecoder& protoConfig) {
        if (protoConfig.has_mode() &&
            protoConfig.mode() == proto::AndroidInputEventConfig::TRACE_MODE_TRACE_ALL) {
            // User has requested the preset for maximal tracing
            return internal::CONFIG_TRACE_ALL;
        }

        impl::TraceConfig config;

        // Parse trace flags
        if (protoConfig.has_trace_dispatcher_input_events() &&
            protoConfig.trace_dispatcher_input_events()) {
            config.flags |= impl::TraceFlag::TRACE_DISPATCHER_INPUT_EVENTS;
        }
        if (protoConfig.has_trace_dispatcher_window_dispatch() &&
            protoConfig.trace_dispatcher_window_dispatch()) {
            config.flags |= impl::TraceFlag::TRACE_DISPATCHER_WINDOW_DISPATCH;
        }

        // Parse trace rules
        auto rulesIt = protoConfig.rules();
        while (rulesIt) {
            proto::AndroidInputEventConfig::TraceRule::Decoder protoRule{rulesIt->as_bytes()};
            config.rules.emplace_back();
            auto& rule = config.rules.back();

            rule.level = protoRule.has_trace_level()
                    ? static_cast<impl::TraceLevel>(protoRule.trace_level())
                    : impl::TraceLevel::TRACE_LEVEL_NONE;

            if (protoRule.has_match_all_packages()) {
                auto pkgIt = protoRule.match_all_packages();
                while (pkgIt) {
                    rule.matchAllPackages.emplace_back(pkgIt->as_std_string());
                    pkgIt++;
                }
            }

            if (protoRule.has_match_any_packages()) {
                auto pkgIt = protoRule.match_any_packages();
                while (pkgIt) {
                    rule.matchAnyPackages.emplace_back(pkgIt->as_std_string());
                    pkgIt++;
                }
            }

            if (protoRule.has_match_secure()) {
                rule.matchSecure = protoRule.match_secure();
            }

            if (protoRule.has_match_ime_connection_active()) {
                rule.matchImeConnectionActive = protoRule.match_ime_connection_active();
            }

            rulesIt++;
        }

        return config;
    }
};

} // namespace android::input_trace