// SPDX-FileCopyrightText: Copyright 2021 yuzu Emulator Project
// SPDX-License-Identifier: GPL-2.0-or-later

#include <algorithm>

#include "core/hid/emulated_controller.h"
#include "core/hid/input_converter.h"

namespace Core::HID {

// Use a common UUID for Virtual Gamepad
constexpr Common::UUID VIRTUAL_UUID =
    Common::UUID{{0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x7, 0xFF, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0}};

// xperia64: 0x9A seems to be the calibrated limit of the circle pad
// Verified by using Input Redirector with very large-value digital inputs
// on the circle pad and calibrating using the system settings application
constexpr int MAX_CIRCLEPAD_POS = 0x9A; // Max value for a circle pad position

EmulatedController::EmulatedController() {}

EmulatedController::~EmulatedController() = default;

void EmulatedController::LoadDevices() {
    LoadVirtualGamepadParams();

    std::ranges::transform(button_params, button_devices.begin(), Common::Input::CreateInputDevice);
    std::ranges::transform(stick_params, stick_devices.begin(), Common::Input::CreateInputDevice);
    std::ranges::transform(motion_params, motion_devices.begin(), Common::Input::CreateInputDevice);

    // Initialize virtual gamepad devices
    std::ranges::transform(virtual_button_params, virtual_button_devices.begin(),
                           Common::Input::CreateInputDevice);
    std::ranges::transform(virtual_stick_params, virtual_stick_devices.begin(),
                           Common::Input::CreateInputDevice);
}

void EmulatedController::LoadVirtualGamepadParams() {
    Common::ParamPackage common_params{};
    common_params.Set("engine", "virtual_gamepad");
    common_params.Set("port", 0);
    for (auto& param : virtual_button_params) {
        param = common_params;
    }
    for (auto& param : virtual_stick_params) {
        param = common_params;
    }

    // TODO(german77): Replace this with an input profile or something better
    virtual_button_params[Settings::NativeButton::A].Set("button", 0);
    virtual_button_params[Settings::NativeButton::B].Set("button", 1);
    virtual_button_params[Settings::NativeButton::X].Set("button", 2);
    virtual_button_params[Settings::NativeButton::Y].Set("button", 3);
    virtual_button_params[Settings::NativeButton::DUp].Set("button", 4);
    virtual_button_params[Settings::NativeButton::DDown].Set("button", 5);
    virtual_button_params[Settings::NativeButton::DLeft].Set("button", 6);
    virtual_button_params[Settings::NativeButton::DRight].Set("button", 7);
    virtual_button_params[Settings::NativeButton::L].Set("button", 8);
    virtual_button_params[Settings::NativeButton::R].Set("button", 9);
    virtual_button_params[Settings::NativeButton::Start].Set("button", 10);
    virtual_button_params[Settings::NativeButton::Select].Set("button", 11);
    virtual_button_params[Settings::NativeButton::Debug].Set("button", 12);
    virtual_button_params[Settings::NativeButton::Gpio14].Set("button", 13);
    virtual_button_params[Settings::NativeButton::ZL].Set("button", 14);
    virtual_button_params[Settings::NativeButton::ZR].Set("button", 15);
    virtual_button_params[Settings::NativeButton::Home].Set("button", 16);

    virtual_stick_params[Settings::NativeAnalog::CirclePad].Set("axis_x", 0);
    virtual_stick_params[Settings::NativeAnalog::CirclePad].Set("axis_y", 1);
    virtual_stick_params[Settings::NativeAnalog::CStick].Set("axis_x", 2);
    virtual_stick_params[Settings::NativeAnalog::CStick].Set("axis_y", 3);
}

void EmulatedController::UnloadInput() {
    for (auto& button : button_devices) {
        button.reset();
    }
    for (auto& stick : stick_devices) {
        stick.reset();
    }
    for (auto& motion : motion_devices) {
        motion.reset();
    }
    for (auto& button : virtual_button_devices) {
        button.reset();
    }
    for (auto& stick : virtual_stick_devices) {
        stick.reset();
    }
}

void EmulatedController::EnableConfiguration() {
    is_configuring = true;
}

void EmulatedController::DisableConfiguration() {
    is_configuring = false;
}

void EmulatedController::ReloadInput() {
    // If you load any device here add the equivalent to the UnloadInput() function
    LoadDevices();
    for (std::size_t index = 0; index < button_devices.size(); ++index) {
        if (!button_devices[index]) {
            continue;
        }
        const auto uuid = Common::UUID{button_params[index].Get("guid", "")};
        button_devices[index]->SetCallback({
            .on_change =
                [this, index, uuid](const Common::Input::CallbackStatus& callback) {
                    SetButton(callback, index, uuid);
                },
        });
        button_devices[index]->ForceUpdate();
    }

    for (std::size_t index = 0; index < stick_devices.size(); ++index) {
        if (!stick_devices[index]) {
            continue;
        }
        const auto uuid = Common::UUID{stick_params[index].Get("guid", "")};
        stick_devices[index]->SetCallback({
            .on_change =
                [this, index, uuid](const Common::Input::CallbackStatus& callback) {
                    SetStick(callback, index, uuid);
                },
        });
        stick_devices[index]->ForceUpdate();
    }

    for (std::size_t index = 0; index < motion_devices.size(); ++index) {
        if (!motion_devices[index]) {
            continue;
        }
        motion_devices[index]->SetCallback({
            .on_change =
                [this, index](const Common::Input::CallbackStatus& callback) {
                    // SetMotion(callback, index);
                },
        });
        motion_devices[index]->ForceUpdate();
    }

    // Register virtual devices. No need to force update
    for (std::size_t index = 0; index < virtual_button_devices.size(); ++index) {
        if (!virtual_button_devices[index]) {
            continue;
        }
        virtual_button_devices[index]->SetCallback({
            .on_change =
                [this, index](const Common::Input::CallbackStatus& callback) {
                    SetButton(callback, index, VIRTUAL_UUID);
                },
        });
    }

    for (std::size_t index = 0; index < virtual_stick_devices.size(); ++index) {
        if (!virtual_stick_devices[index]) {
            continue;
        }
        virtual_stick_devices[index]->SetCallback({
            .on_change =
                [this, index](const Common::Input::CallbackStatus& callback) {
                    SetStick(callback, index, VIRTUAL_UUID);
                },
        });
    }
}

void EmulatedController::ReloadFromSettings() {
    const auto& player = Settings::values.players.GetValue();
    for (std::size_t i = 0; i < player.buttons.size(); i++) {
        button_params[i] = Common::ParamPackage(player.buttons[i]);
    }
    for (std::size_t i = 0; i < player.analogs.size(); i++) {
        stick_params[i] = Common::ParamPackage(player.analogs[i]);
    }
    for (std::size_t index = 0; index < player.motions.size(); ++index) {
        motion_params[index] = Common::ParamPackage(player.motions[index]);
    }

    ReloadInput();
}

void EmulatedController::SaveCurrentConfig() {
    auto& player = Settings::values.players.GetValue();
    for (std::size_t index = 0; index < player.buttons.size(); ++index) {
        player.buttons[index] = button_params[index].Serialize();
    }
    for (std::size_t index = 0; index < player.analogs.size(); ++index) {
        player.analogs[index] = stick_params[index].Serialize();
    }
    for (std::size_t index = 0; index < player.motions.size(); ++index) {
        player.motions[index] = motion_params[index].Serialize();
    }
}

std::vector<Common::ParamPackage> EmulatedController::GetMappedDevices() const {
    std::vector<Common::ParamPackage> devices;
    for (const auto& param : button_params) {
        if (!param.Has("engine")) {
            continue;
        }
        const auto devices_it = std::find_if(
            devices.begin(), devices.end(), [&param](const Common::ParamPackage& param_) {
                return param.Get("engine", "") == param_.Get("engine", "") &&
                       param.Get("guid", "") == param_.Get("guid", "") &&
                       param.Get("port", 0) == param_.Get("port", 0) &&
                       param.Get("pad", 0) == param_.Get("pad", 0);
            });
        if (devices_it != devices.end()) {
            continue;
        }

        auto& device = devices.emplace_back();
        device.Set("engine", param.Get("engine", ""));
        device.Set("guid", param.Get("guid", ""));
        device.Set("port", param.Get("port", 0));
        device.Set("pad", param.Get("pad", 0));
    }

    for (const auto& param : stick_params) {
        if (!param.Has("engine")) {
            continue;
        }
        if (param.Get("engine", "") == "analog_from_button") {
            continue;
        }
        const auto devices_it = std::find_if(
            devices.begin(), devices.end(), [&param](const Common::ParamPackage& param_) {
                return param.Get("engine", "") == param_.Get("engine", "") &&
                       param.Get("guid", "") == param_.Get("guid", "") &&
                       param.Get("port", 0) == param_.Get("port", 0) &&
                       param.Get("pad", 0) == param_.Get("pad", 0);
            });
        if (devices_it != devices.end()) {
            continue;
        }

        auto& device = devices.emplace_back();
        device.Set("engine", param.Get("engine", ""));
        device.Set("guid", param.Get("guid", ""));
        device.Set("port", param.Get("port", 0));
        device.Set("pad", param.Get("pad", 0));
    }
    return devices;
}

Common::ParamPackage EmulatedController::GetButtonParam(std::size_t index) const {
    if (index >= button_params.size()) {
        return {};
    }
    return button_params[index];
}

Common::ParamPackage EmulatedController::GetStickParam(std::size_t index) const {
    if (index >= stick_params.size()) {
        return {};
    }
    return stick_params[index];
}

Common::ParamPackage EmulatedController::GetMotionParam(std::size_t index) const {
    if (index >= motion_params.size()) {
        return {};
    }
    return motion_params[index];
}

void EmulatedController::SetButtonParam(std::size_t index, Common::ParamPackage param) {
    if (index >= button_params.size()) {
        return;
    }
    button_params[index] = std::move(param);
    ReloadInput();
}

void EmulatedController::SetStickParam(std::size_t index, Common::ParamPackage param) {
    if (index >= stick_params.size()) {
        return;
    }
    stick_params[index] = std::move(param);
    ReloadInput();
}

void EmulatedController::SetMotionParam(std::size_t index, Common::ParamPackage param) {
    if (index >= motion_params.size()) {
        return;
    }
    motion_params[index] = std::move(param);
    ReloadInput();
}

ButtonValues EmulatedController::GetButtonsValues() const {
    std::scoped_lock lock{mutex};
    return controller.button_values;
}

SticksValues EmulatedController::GetSticksValues() const {
    std::scoped_lock lock{mutex};
    return controller.stick_values;
}

PadState EmulatedController::GetPadState() const {
    std::scoped_lock lock{mutex};
    if (is_configuring) {
        return {};
    }
    return controller.pad_state;
}

ExtraState EmulatedController::GetExtraState() const {
    std::scoped_lock lock{mutex};
    if (is_configuring) {
        return {};
    }
    return controller.extra_state;
}

AnalogSticks EmulatedController::GetSticks() const {
    std::unique_lock lock{mutex};
    if (is_configuring) {
        return {};
    }
    return controller.analog_stick_state;
}

void EmulatedController::SetButton(const Common::Input::CallbackStatus& callback, std::size_t index,
                                   Common::UUID uuid) {
    if (index >= controller.button_values.size()) {
        return;
    }
    std::unique_lock lock{mutex};
    bool value_changed = false;
    const auto new_status = TransformToButton(callback);
    auto& current_status = controller.button_values[index];

    // Only read button values that have the same uuid or are pressed once
    if (current_status.uuid != uuid) {
        if (!new_status.value) {
            return;
        }
    }

    current_status.toggle = new_status.toggle;
    current_status.uuid = uuid;

    // Update button status with current
    if (!current_status.toggle) {
        current_status.locked = false;
        if (current_status.value != new_status.value) {
            current_status.value = new_status.value;
            value_changed = true;
        }
    } else {
        // Toggle button and lock status
        if (new_status.value && !current_status.locked) {
            current_status.locked = true;
            current_status.value = !current_status.value;
            value_changed = true;
        }

        // Unlock button ready for next press
        if (!new_status.value && current_status.locked) {
            current_status.locked = false;
        }
    }

    if (!value_changed) {
        return;
    }

    if (is_configuring) {
        controller.pad_state.hex = 0;
        lock.unlock();
        TriggerOnChange(ControllerTriggerType::Button, false);
        return;
    }

    switch (index) {
    case Settings::NativeButton::A:
        controller.pad_state.a.Assign(current_status.value);
        break;
    case Settings::NativeButton::B:
        controller.pad_state.b.Assign(current_status.value);
        break;
    case Settings::NativeButton::X:
        controller.pad_state.x.Assign(current_status.value);
        break;
    case Settings::NativeButton::Y:
        controller.pad_state.y.Assign(current_status.value);
        break;
    case Settings::NativeButton::L:
        controller.pad_state.l.Assign(current_status.value);
        break;
    case Settings::NativeButton::R:
        controller.pad_state.r.Assign(current_status.value);
        break;
    case Settings::NativeButton::ZL:
        controller.extra_state.zl = current_status.value;
        break;
    case Settings::NativeButton::ZR:
        controller.extra_state.zr = current_status.value;
        break;
    case Settings::NativeButton::Start:
        controller.pad_state.start.Assign(current_status.value);
        break;
    case Settings::NativeButton::Select:
        controller.pad_state.select.Assign(current_status.value);
        break;
    case Settings::NativeButton::DLeft:
        controller.pad_state.left.Assign(current_status.value);
        break;
    case Settings::NativeButton::DUp:
        controller.pad_state.up.Assign(current_status.value);
        break;
    case Settings::NativeButton::DRight:
        controller.pad_state.right.Assign(current_status.value);
        break;
    case Settings::NativeButton::DDown:
        controller.pad_state.down.Assign(current_status.value);
        break;
    case Settings::NativeButton::Debug:
        controller.pad_state.debug.Assign(current_status.value);
        break;
    case Settings::NativeButton::Gpio14:
        controller.pad_state.gpio14.Assign(current_status.value);
        break;
    }

    lock.unlock();
    TriggerOnChange(ControllerTriggerType::Button, true);
}

void EmulatedController::SetStick(const Common::Input::CallbackStatus& callback, std::size_t index,
                                  Common::UUID uuid) {
    if (index >= controller.stick_values.size()) {
        return;
    }
    std::unique_lock lock{mutex};
    const auto stick_value = TransformToStick(callback);

    // Only read stick values that have the same uuid or are over the threshold to avoid flapping
    if (controller.stick_values[index].uuid != uuid) {
        if (!stick_value.down && !stick_value.up && !stick_value.left && !stick_value.right) {
            return;
        }
    }

    controller.stick_values[index] = stick_value;
    controller.stick_values[index].uuid = uuid;

    if (is_configuring) {
        controller.analog_stick_state.circle_pad = {};
        controller.analog_stick_state.c_stick = {};
        lock.unlock();
        TriggerOnChange(ControllerTriggerType::Stick, false);
        return;
    }

    const AnalogStickState stick{
        .x = static_cast<s16>(
            std::roundf(controller.stick_values[index].x.value * MAX_CIRCLEPAD_POS)),
        .y = static_cast<s16>(
            std::roundf(controller.stick_values[index].y.value * MAX_CIRCLEPAD_POS)),
    };

    switch (index) {
    case Settings::NativeAnalog::CirclePad:
        controller.analog_stick_state.circle_pad = stick;
        controller.pad_state.circle_left.Assign(controller.stick_values[index].left);
        controller.pad_state.circle_up.Assign(controller.stick_values[index].up);
        controller.pad_state.circle_right.Assign(controller.stick_values[index].right);
        controller.pad_state.circle_down.Assign(controller.stick_values[index].down);
        break;
    case Settings::NativeAnalog::CStick:
        controller.analog_stick_state.c_stick = stick;
        controller.extra_state.c_stick_left = controller.stick_values[index].left;
        controller.extra_state.c_stick_up = controller.stick_values[index].up;
        controller.extra_state.c_stick_right = controller.stick_values[index].right;
        controller.extra_state.c_stick_down = controller.stick_values[index].down;
        break;
    }

    lock.unlock();
    TriggerOnChange(ControllerTriggerType::Stick, true);
}

void EmulatedController::TriggerOnChange(ControllerTriggerType type, bool is_hid_service_update) {
    std::scoped_lock lock{callback_mutex};
    for (const auto& poller_pair : callback_list) {
        const ControllerUpdateCallback& poller = poller_pair.second;
        if (!is_hid_service_update && poller.is_hid_service) {
            continue;
        }
        if (poller.on_change) {
            poller.on_change(type);
        }
    }
}

int EmulatedController::SetCallback(ControllerUpdateCallback update_callback) {
    std::scoped_lock lock{callback_mutex};
    callback_list.insert_or_assign(last_callback_key, std::move(update_callback));
    return last_callback_key++;
}

void EmulatedController::DeleteCallback(int key) {
    std::scoped_lock lock{callback_mutex};
    const auto& iterator = callback_list.find(key);
    if (iterator == callback_list.end()) {
        LOG_ERROR(Input, "Tried to delete non-existent callback {}", key);
        return;
    }
    callback_list.erase(iterator);
}

} // namespace Core::HID