#include "InteractiveObjectState.h"
#include <algorithm>
#include <utility>

namespace FRG {

void InteractiveObjectState::moveTo(
	const Eigen::Vector3f& target, float durationSec, std::string onCompleteName)
{
	if (isAnimating) return;
	AnimTask task;
	task.type = AnimTask::Type::Move;
	task.startPos = position;
	task.startRotY = rotationY;
	task.startScale = scale;
	task.targetPos = target;
	task.targetRotY = rotationY;
	task.targetScale = scale;
	task.durationMs = durationSec * 1000.f;
	task.onCompleteName = std::move(onCompleteName);
	animTask = std::move(task);
	isAnimating = true;
}

void InteractiveObjectState::rotateTo(
	float targetRotY, float durationSec, std::string onCompleteName)
{
	if (isAnimating) return;
	AnimTask task;
	task.type = AnimTask::Type::Rotate;
	task.startPos = position;
	task.startRotY = rotationY;
	task.startScale = scale;
	task.targetPos = position;
	task.targetRotY = targetRotY;
	task.targetScale = scale;
	task.durationMs = durationSec * 1000.f;
	task.onCompleteName = std::move(onCompleteName);
	animTask = std::move(task);
	isAnimating = true;
}

void InteractiveObjectState::scaleTo(
	float targetScale, float durationSec, std::string onCompleteName)
{
	if (isAnimating) return;
	AnimTask task;
	task.type = AnimTask::Type::Scale;
	task.startPos = position;
	task.startRotY = rotationY;
	task.startScale = scale;
	task.targetPos = position;
	task.targetRotY = rotationY;
	task.targetScale = targetScale;
	task.durationMs = durationSec * 1000.f;
	task.onCompleteName = std::move(onCompleteName);
	animTask = std::move(task);
	isAnimating = true;
}

void InteractiveObjectState::fadeTo(
	float targetAlpha, float durationSec, std::string onCompleteName)
{
	if (isAnimating) return;
	AnimTask task;
	task.type = AnimTask::Type::Fade;
	task.startPos = position;
	task.startRotY = rotationY;
	task.startScale = alpha;
	task.targetPos = position;
	task.targetRotY = rotationY;
	task.targetScale = targetAlpha;
	task.durationMs = durationSec * 1000.f;
	task.onCompleteName = std::move(onCompleteName);
	animTask = std::move(task);
	isAnimating = true;
}

InteractiveObjectUpdateEvents InteractiveObjectState::update(std::int64_t deltaMs)
{
	InteractiveObjectUpdateEvents events;
	if (!isAnimating || !animTask) return events;

	AnimTask& task = *animTask;
	task.elapsedMs += static_cast<float>(deltaMs);
	const float duration = (std::max)(task.durationMs, 0.001f);
	const float t = (std::min)(task.elapsedMs / duration, 1.0f);

	switch (task.type) {
	case AnimTask::Type::Move:
		position = task.startPos + (task.targetPos - task.startPos) * t;
		break;
	case AnimTask::Type::Rotate:
		rotationY = task.startRotY + (task.targetRotY - task.startRotY) * t;
		break;
	case AnimTask::Type::Scale:
		scale = task.startScale + (task.targetScale - task.startScale) * t;
		break;
	case AnimTask::Type::Fade:
		alpha = task.startScale + (task.targetScale - task.startScale) * t;
		break;
	}

	if (t < 1.0f) return events;
	position = task.targetPos;
	rotationY = task.targetRotY;
	if (task.type == AnimTask::Type::Fade)
		alpha = task.targetScale;
	else
		scale = task.targetScale;
	events.onCompleteName = std::move(task.onCompleteName);
	animTask.reset();
	isAnimating = false;
	return events;
}

void InteractiveObjectState::save(nlohmann::json& out) const
{
	out["positionX"] = position.x();
	out["positionY"] = position.y();
	out["positionZ"] = position.z();
	out["rotationY"] = rotationY;
	out["scale"] = scale;
	out["alpha"] = alpha;
	out["isActive"] = isActive;
	out["isAnimating"] = isAnimating;

	if (isAnimating && animTask) {
		out["animTask"] = {
			{"type", static_cast<int>(animTask->type)},
			{"startPosX", animTask->startPos.x()},
			{"startPosY", animTask->startPos.y()},
			{"startPosZ", animTask->startPos.z()},
			{"startRotY", animTask->startRotY},
			{"startScale", animTask->startScale},
			{"targetPosX", animTask->targetPos.x()},
			{"targetPosY", animTask->targetPos.y()},
			{"targetPosZ", animTask->targetPos.z()},
			{"targetRotY", animTask->targetRotY},
			{"targetScale", animTask->targetScale},
			{"durationMs", animTask->durationMs},
			{"elapsedMs", animTask->elapsedMs},
			{"onCompleteName", animTask->onCompleteName}};
	}
}

void InteractiveObjectState::load(const nlohmann::json& in)
{
	position.x() = in.value("positionX", position.x());
	position.y() = in.value("positionY", position.y());
	position.z() = in.value("positionZ", position.z());
	rotationY = in.value("rotationY", rotationY);
	scale = in.value("scale", scale);
	alpha = in.value("alpha", alpha);
	isActive = in.value("isActive", isActive);
	isAnimating = in.value("isAnimating", false);
	animTask.reset();

	if (!isAnimating || !in.contains("animTask") ||
		!in["animTask"].is_object()) {
		return;
	}
	const auto& value = in["animTask"];
	AnimTask task;
	task.type = static_cast<AnimTask::Type>(value.value("type", 0));
	task.startPos = {value.value("startPosX", 0.f),
		value.value("startPosY", 0.f), value.value("startPosZ", 0.f)};
	task.startRotY = value.value("startRotY", 0.f);
	task.startScale = value.value("startScale", 1.f);
	task.targetPos = {value.value("targetPosX", 0.f),
		value.value("targetPosY", 0.f), value.value("targetPosZ", 0.f)};
	task.targetRotY = value.value("targetRotY", 0.f);
	task.targetScale = value.value("targetScale", 1.f);
	task.durationMs = value.value("durationMs", 1000.f);
	task.elapsedMs = value.value("elapsedMs", 0.f);
	task.onCompleteName =
		value.value("onCompleteName", std::string());
	animTask = std::move(task);
}

} // namespace FRG