#include "DatExporter.h"
#include "animation/targetShapeSet.h"
#include <boost/lexical_cast.hpp>

using std::chrono::duration;
using std::chrono::duration_cast;
using std::string;

DatExporter::DatExporter(const ShapeSet& targetShapeSet, double frameRate, bool convertToPrestonBlair) :
	frameRate(frameRate),
	convertToPrestonBlair(convertToPrestonBlair),
	prestonBlairShapeNames {
		{ Shape::A, "MBP" },
		{ Shape::B, "etc" },
		{ Shape::C, "E" },
		{ Shape::D, "AI" },
		{ Shape::E, "O" },
		{ Shape::F, "U" },
		{ Shape::G, "FV" },
		{ Shape::H, "L" },
		{ Shape::X, "rest" },
	}
{
	// Animation works with a fixed frame rate of 100.
	// Downsampling to much less than 25 fps may result in dropped frames.
	// Upsampling to more than 100 fps doesn't make sense.
	const double minFrameRate = 24.0;
	const double maxFrameRate = 100.0;

	if (frameRate < minFrameRate || frameRate > maxFrameRate) {
		throw std::runtime_error(fmt::format("Frame rate must be between {} and {} fps.", minFrameRate, maxFrameRate));
	}

	if (convertToPrestonBlair) {
		for (Shape shape : targetShapeSet) {
			if (prestonBlairShapeNames.find(shape) == prestonBlairShapeNames.end()) {
				throw std::runtime_error(fmt::format("Mouth shape {} cannot be converted to Preston Blair shape names."));
			}
		}
	}
}

void DatExporter::exportAnimation(const ExporterInput& input, std::ostream& outputStream) {
	outputStream << "MohoSwitch1" << "\n";

	// Output shapes with start times
	int lastFrameNumber = 0;
	for (auto& timedShape : input.animation) {
		const int frameNumber = toFrameNumber(timedShape.getStart());
		if (frameNumber == lastFrameNumber) continue;

		const string shapeName = toString(timedShape.getValue());
		outputStream << frameNumber << " " << shapeName << "\n";
		lastFrameNumber = frameNumber;
	}

	// Output closed mouth with end time
	int frameNumber = toFrameNumber(input.animation.getRange().getEnd());
	if (frameNumber == lastFrameNumber) ++frameNumber;
	const string shapeName = toString(convertToTargetShapeSet(Shape::X, input.targetShapeSet));
	outputStream << frameNumber << " " << shapeName << "\n";
}

string DatExporter::toString(Shape shape) const {
	return convertToPrestonBlair
		? prestonBlairShapeNames.at(shape)
		: boost::lexical_cast<std::string>(shape);
}

int DatExporter::toFrameNumber(centiseconds time) const {
	return 1 + static_cast<int>(frameRate * duration_cast<duration<double>>(time).count());
}