#include "ControlPanel.h"

#include <format>
#include <iostream>
#include <ranges>

#include "CallbackManager.h"
#include "imgui.h"


ControlPanel::ControlPanel(
    std::shared_ptr<Graphics> graphics,
    std::shared_ptr<MachineState> machine_state,
    std::shared_ptr<CallbackManager> callback_manager
) : graphics{std::move(graphics)},
    machine_state{std::move(machine_state)},
    callback_manager{std::move(callback_manager)}
{
    this->callback_manager->ips_callback.push_back(std::bind(
        &ControlPanel::initial_ips_load,
        this,
        std::placeholders::_1
    ));
}

void ControlPanel::render()
{
    int starting_speed = this->ips;

    constexpr auto full_width = ImVec2(-FLT_MIN, 0.0f);

    if (ImGui::Begin("Chip-8 - Controls"))
    {
        if (ImGui::Button("Load Rom", full_width))
        {
            this->on_click_load_rom();
        }

        if (ImGui::Button(run ? "Pause" : "Run", full_width))
        {
            this->run = !run;
            if (this->run)
            {
                this->callback_manager->trigger(this->callback_manager->resume_callback);
            }
            else
            {
                this->callback_manager->trigger(this->callback_manager->stop_callback);
            }
        }

        ImGui::Text("Status: %s", "Stopped");

        ImGui::SeparatorText("Debug");


        if (ImGui::Button("Step One", full_width))
        {
            this->callback_manager->trigger(this->callback_manager->step_callback, 1);
        }

        if (ImGui::Button(std::format("Step +{}", steps).data(), full_width))
        {
            this->callback_manager->trigger(this->callback_manager->step_callback, steps);
        }

        ImGui::PushItemWidth(ImGui::GetContentRegionAvail().x);
        ImGui::InputInt("##steps", &steps);
        ImGui::PopItemWidth();


        ImGui::SeparatorText("Emulation speed (IPS)");

        ImGui::PushItemWidth(ImGui::GetContentRegionAvail().x);
        ImGui::InputInt("##speed", &ips);
        ImGui::PopItemWidth();

        ImGui::SeparatorText("");

        if (ImGui::Button("Reset", full_width))
        {
            this->callback_manager->trigger(this->callback_manager->reset_callback);
        }
        if (ImGui::Button("Reload ROM", full_width))
        {
            this->callback_manager->trigger(this->callback_manager->reload_callback);
        }
    }

    if (ips < 0)
    {
        ips = 0;
    }
    if (steps < 1)
    {
        steps = 1;
    }

    if (starting_speed != ips)
    {
        this->callback_manager->trigger(this->callback_manager->ips_callback, ips);
    }

    ImGui::End();
}

void ControlPanel::on_click_load_rom()
{
    constexpr SDL_DialogFileFilter filters[] = {
        {"CHIP8 ROMs", "ch8"},
        {"All files", "*"}
    };

    SDL_ShowOpenFileDialog(
        on_callback_load_rom,
        this,
        graphics->get_window().get(),
        filters,
        std::size(filters),
        SDL_GetCurrentDirectory(),
        false
    );
}

void ControlPanel::on_callback_load_rom(void* self, const char* const* filelist, int)
{
    const auto control_panel = static_cast<ControlPanel*>(self);

    if (!filelist || !*filelist)
    {
        return;
    }

    control_panel->callback_manager->trigger(
        control_panel->callback_manager->rom_load_callback,
        std::string(filelist[0])
    );
}

void ControlPanel::initial_ips_load(int ips)
{
    this->ips = ips;
}