#pragma once
#include "FluidSim/Scenario.hpp"
#include "FluidSim/ScenarioCatalog.hpp"
#include "FluidSim/TwoStrokeScenario.hpp"
#include <memory>
#include <mutex>

namespace fluidsim::port {
// Shared desktop controls and snapshots. Each simulation owns its state lock.
class DesktopScenario {
public:
    explicit DesktopScenario(const ScenarioExample& e)
        : DesktopScenario(e.kind,e.two,e.exhaust,e.junctions,e.engine,e.title) {}
    explicit DesktopScenario(ScenarioKind kind, TwoStrokeConfig config = {}, ExhaustConfig exhaust = {}, JunctionConfig junctions = {}, EngineConfig engine = {}, std::string name = {}) : name_(std::move(name)),exhaust_(exhaust),junctions_(junctions) {
        if (kind == ScenarioKind::TwoStroke)
            two_ = std::make_unique<TwoStrokeScenario>(44100, config);
        else {
            if(!engine.cylinders)engine=preset_engine_definition(kind==ScenarioKind::SaabB205?
                FourStrokePreset::SaabB205:kind==ScenarioKind::AmericanV8?FourStrokePreset::AmericanV8:FourStrokePreset::Twin).engine;
            four_ = std::make_unique<FourStrokeScenario>(44100,std::move(engine),exhaust,junctions);
        }
    }
    AudioFrame process() {
        const std::lock_guard lock(mutex_);
        if (four_)
            return four_->process();
        return two_->process();
    }
    void set_controls(float pedal, float load, float clutch) {
        visit([&](auto& scenario) { pedal_=pedal;load_=load;clutch_=clutch;scenario.set_controls(pedal, load, clutch); });
    }
    void set_starter(bool engaged) { visit([&](auto& scenario) { starter_=engaged;scenario.set_starter(engaged); }); }
    void shift_up() { visit([](auto& scenario) { scenario.shift_up(); }); }
    void shift_down() { visit([](auto& scenario) { scenario.shift_down(); }); }
    void set_neutral() { visit([](auto& scenario) { scenario.set_neutral(); }); }
    void set_pipe_solver(PipeSolver solver) { visit([&](auto& scenario) { solver_=solver;scenario.set_pipe_solver(solver); }); }
    void set_audio_scene(OutdoorScene scene) {
        visit([&](auto& scenario) { scene_=scene;scenario.set_audio_scene(scene); });
    }
    void set_listener(AudioListener listener) {
        visit([&](auto& scenario) { listener_=listener;scenario.set_listener(listener); });
    }
    void set_tuning(const EngineConfig& tuning) {
        const std::lock_guard lock(mutex_);
        if(four_)four_->set_tuning(tuning);
    }
    // Build on a background thread. Publishing takes the same lock as process(),
    // so no solver/port pointers can be observed during the swap.
    void rebuild_engine(const EngineConfig& engine) {
        validate_engine_config(engine,"pipe rebuild");
        auto replacement=std::make_unique<FourStrokeScenario>(44100,engine,exhaust_,junctions_);
        {
            const std::lock_guard lock(mutex_);
            if(!four_)throw std::invalid_argument("Live editor requires a four-stroke engine");
            replacement->set_controls(pedal_,load_,clutch_);
            replacement->set_starter(starter_);replacement->set_pipe_solver(solver_);
            replacement->set_audio_scene(scene_);replacement->set_listener(listener_);
            four_.swap(replacement);
        }
    }
    void set_cells_per_meter(float density) {
        mesh_cell_count(.1f,density);
        EngineConfig engine;TwoStrokeConfig two_config;bool is_two;
        {
            const std::lock_guard lock(mutex_);
            is_two=bool(two_);
            if(is_two) two_config=two_->configuration; else engine=four_->engine_config;
        }
        std::unique_ptr<FourStrokeScenario> next_four;
        std::unique_ptr<TwoStrokeScenario> next_two;
        if(is_two) { two_config.cells_per_meter=density;two_config.exhaust_cell_length=1/density;next_two=std::make_unique<TwoStrokeScenario>(44100,two_config); }
        else { engine.cells_per_meter=density;next_four=std::make_unique<FourStrokeScenario>(44100,engine,exhaust_,junctions_); }
        {
            const std::lock_guard lock(mutex_);
            const auto restore=[&](auto& scenario) {
                scenario.set_controls(pedal_,load_,clutch_);scenario.set_starter(starter_);
                scenario.set_pipe_solver(solver_);scenario.set_audio_scene(scene_);scenario.set_listener(listener_);
            };
            if(is_two) {restore(*next_two);two_.swap(next_two);}
            else {restore(*next_four);four_.swap(next_four);}
        }
    }
    ScenarioSnapshot snapshot() const {
        const std::lock_guard lock(mutex_);
        if (four_) { auto s=four_->snapshot();s.example_name=name_;s.cells_per_meter=four_->engine_config.cells_per_meter;return s; }
        const auto source = two_->snapshot();
        ScenarioSnapshot s;
        s.example_name=name_;
        s.pipe_solver=two_->pipes.front().solver;
        s.two_stroke = true;
        s.cells_per_meter=two_->configuration.cells_per_meter;
        s.cylinder_angles[0]=two_->crankshaft.angle;
        s.cylinder_count = 1;
        s.racing_exhaust = two_->configuration.exhaust == TwoStrokeExhaust::Racing;
        s.rpm = source.rpm;
        s.speed_kmh = two_->vehicle.speed * 3.6f;
        s.kinetic_energy = two_->vehicle.kinetic_energy();
        s.gear = two_->vehicle.current_gear;
        s.clutch = two_->clutch;
        s.average_power = two_->crankshaft.average_power;
        s.average_torque = two_->crankshaft.average_torque;
        s.cylinder_pressure1 = source.cylinder_pressure;
        s.cylinder_temperature1 = two_->cylinder.temperature();
        s.cylinder_piston_fraction1 =
            (two_->cylinder.volume - two_->cylinder.clearance_volume()) / two_->cylinder.swept_volume();
        s.crankcase_pressure = source.crankcase_pressure;
        s.intake_pressure = source.intake_pressure;
        s.exhaust_pressure = two_->pipes[3].state(0).pressure;
        s.throttle = source.throttle;
        s.pedal = source.pedal;
        s.target_afr = two_->carburetor.indicated_afr();
        s.valve1_intake_area = source.transfer_area;
        s.valve1_exhaust_area = source.exhaust_area;
        s.reed_open = source.reed_open;
        s.fuel_cut = source.fuel_cut;
        s.ignition_cut = source.ignition_cut;
        s.idle_control = two_->ecu.idle_active();
        s.rev_limit1 = two_->ecu.rev_limited();
        s.audio_scene = source.audio_scene;
        s.intake_flow = two_->intake_flow;
        s.exhaust_flow = two_->exhaust_flow;
        s.capture_pipes(two_->pipes);
        two_->capture_geometry(s);
        return s;
    }

private:
    template<class Function> void visit(Function&& function) {
        const std::lock_guard lock(mutex_);
        if (four_) function(*four_);
        else function(*two_);
    }
    std::string name_;
    ExhaustConfig exhaust_;
    JunctionConfig junctions_;
    float pedal_{},load_{},clutch_{};
    bool starter_{};
    PipeSolver solver_{PipeSolver::Rusanov};
    OutdoorScene scene_{OutdoorScene::Wall};
    AudioListener listener_{};
    std::unique_ptr<FourStrokeScenario> four_;
    std::unique_ptr<TwoStrokeScenario> two_;
    mutable std::mutex mutex_;
};
} // namespace fluidsim::port