#include <GL/glew.h>

#include <imgui.h>
#include <backends/imgui_impl_opengl3.h>
#include <backends/imgui_impl_sdl.h>

#include "gooey.h"
#include "orbits.h"


bool
gooInit(SDL_Window* window, SDL_GLContext gl_context)
{
	IMGUI_CHECKVERSION();
	ImGui::CreateContext();
	ImGuiIO& io = ImGui::GetIO();
	io.IniFilename = NULL;  // don't save window state to imgui.ini
	ImGui::StyleColorsDark();

	bool ret = true;
	ret = ret && ImGui_ImplSDL2_InitForOpenGL(window, gl_context);
	ret = ret && ImGui_ImplOpenGL3_Init();

	return ret;
}

void
gooFree()
{
	ImGui_ImplOpenGL3_Shutdown();
	ImGui_ImplSDL2_Shutdown();
	ImGui::DestroyContext();
}

bool
gooProcessEvent(SDL_Event& e)
{
	ImGui_ImplSDL2_ProcessEvent(&e);
	return (ImGui::GetIO().WantCaptureMouse
		|| ImGui::GetIO().WantCaptureKeyboard);
}

void
gooDraw(SDL_Window* window, orbital_elements& orbit, uint& time_step)
{
	ImGui_ImplOpenGL3_NewFrame();
	ImGui_ImplSDL2_NewFrame(window);
	ImGui::NewFrame();

	const static int w = 300;
	int x = 0, y = 0;
	SDL_GetWindowSize(window, &x, &y);
	ImGui::SetNextWindowPos(ImVec2(x - w, 0));
	ImGui::SetNextWindowSize(ImVec2(w, y));
	ImGui::Begin("Orbital Elements");

	ImGui::Text("iota, inclination:            %f", orbit.iota);
	ImGui::Text("omega, argument of periapsis: %f", orbit.omega);
	ImGui::Text("mu, gravitational parameter:  %f", orbit.mu);
	ImGui::Text("nu, true anomoly: ");
	ImGui::InputDouble("##orbit.nu", &orbit.nu, 0.1f);
	ImGui::SameLine();
	ImGui::Text(" radians");
	ImGui::Spacing();

	ImGui::Separator();
	ImGui::Spacing();
	ImGui::Text("Ellipse Parameters:");
	ImGui::Text("semi-major axis, a:     ");
	ImGui::InputDouble("##orbit.ep.a", &orbit.ep.a, 1000.0f);
	ImGui::SameLine();
	ImGui::Text(" km");
	ImGui::Text("semi-minor axis, b:     %f km", orbit.ep.b);
	ImGui::Text("eccentricity, e:        ");
	ImGui::InputDouble("##orbit.ep.e", &orbit.ep.e, 0.01f);
	ImGui::Text("linear eccentricity, c: %f km", orbit.ep.c);
	ImGui::Spacing();

	ImGui::Separator();
	ImGui::Spacing();
	ImGui::Text("Other Parameters");
	ImGui::Spacing();
	ImGui::Text("time_step:");
	ImGui::SameLine();
	uint step = 1;
	ImGui::InputScalar("##other.time_step", ImGuiDataType_U32, &time_step, &step);
	ImGui::Spacing();
	ImGui::Text("Satellite Parameters:");
	ImGui::Text("position:");
	ImGui::Text("	x: %f km", orbit.pos.x);
	ImGui::Text("	y: %f km", orbit.pos.y);
	ImGui::Text("	z: %f km", orbit.pos.z);
	ImGui::Text("radial velocity:");
	ImGui::Text("flight path angle:");

	ImGui::End();
	ImGui::Render();
	ImGui_ImplOpenGL3_RenderDrawData(ImGui::GetDrawData());
}