#include "df0001.h"
#include "ROOT/RDataFrame.hxx"
#include "TApplication.h"

void fill_tree(const char* treeName, const char* fileName)
{
	ROOT::RDataFrame d(10);
	int i{ 0 };
	d.Define("b1", [&i]() {return static_cast<double>(i); })
		.Define("b2", [&i]() {auto j = i * i; ++i; return j; })
		.Snapshot(treeName, fileName);
}

int df0001_introduction()
{
	// We prepare an input tree to run on
	auto fileName = "df001_introduction.root";
	auto treeName = "myTree";
	fill_tree(treeName, fileName);

	ROOT::RDataFrame d(treeName, fileName, { "b1" });

	auto cutb1 = [](double b1) { return b1 < 5.; };
	auto cutb1b2 = [](int b2, double b1) { return b2 % 2 && b1 < 4.; };

	auto entries1 = d.Filter(cutb1) // <- no column name specified here!
		.Filter(cutb1b2, { "b2", "b1" })
		.Count();

	std::cout << *entries1 << " entries passed all filters" << std::endl;

	auto entries2 = d.Filter("b1 < 10.").Count();
	std::cout << *entries2 << " entries passed the string filter" << std::endl;

	return 0;
}

int main(int argc, char** argv)
{
	TApplication app("app", &argc, argv);
	df0001_introduction();
	app.Run();
	return 0;
}