#include <gtest/gtest.h>

#include "nfc.hh"   // for illegal_utf8 exception
#include <vector>


namespace {

struct TestEntry
{
	std::string input;
	std::u32string output;
};

std::string uplus(const std::u32string& u32)
{
	std::string ret; ret.reserve(u32.size()*6);
	char hexa[16];
	for(auto c:u32)
	{
		snprintf(hexa,15, "<U+%04X>", unsigned(c));
		ret += hexa;
	}
	return ret;
}

std::ostream& operator<<(std::ostream& o, const TestEntry& tt)
{
	return o << "input=«" << tt.input << "», output=«" << uplus(tt.output) << "» ";
}


const char     nullo[4]   = {0,0,0,0};
const char32_t nullo32[4] = {0,0,0,0};

const std::vector<TestEntry> testValues =
	{
		{ ""      , U""      },  // always start with the simple case ;-)
		{ "123"   , U"123"   },  // some ASCII digits. Still easy.
		{ "\n\\\b", U"\n\\\b"  },  // backslash escapes for ASCII and control chars
		{ "ä"     , U"a\u0308"     },  // <U+00E4> small a with diaeresis -> decompose ä
		{ "\xc4\x85" , U"a\u0328"   },  // <U+0105> small a with ogonek -> decompose ą

		{ "a\xcc\x88", U"a\u0308" }, // a + <U+0308> combining diaresis
		{ "a\xcc\xa8", U"a\u0328" }, // a + <U+0328> combining ogonek
		{ "a\xcc\xa8\xcc\x88", U"a\u0328\u0308" }, // a + <U+0328> + <U+0308> ( ogonek +  diaresis)
		{ "a\xcc\x88\xcc\xa8", U"a\u0328\u0308" }, // a + <U+0308> + <U+0328> ( diaeresis + ogonek) -> canonicalOrdering reorders the accents!

		// ogonek sorts before diaeresis or breve-below:
		{ "ä\xcc\xa8ü\xcc\xa8ḫ\xcc\xa8", U"a\u0328\u0308u\u0328\u0308h\u0328\u032e"}, // ä + ogonek, ü + ogonek, h-breve-below + ogonek

		{ "a\xcc\x85\xcc\xbc", U"a\u033c\u0305" }, // a + <U+0305> + <U+033C> ( overline + seagull_below) -> canonicalOrdering reorders the accents!
		{ "a\xcc\xbc\xcc\x85", U"a\u033c\u0305" }, // a + <U+033C> + <U+0305> ( seagull_below + overline)
		{ "\xe1\xba\xad", U"a\u0323\u0302" }, // Vietnamese: ậ <U+1EAD> = a + <U+0323> + <U+0302> = a + dot below + circumflex
		{ "\xe1\xba\xad\xcc\x88\xcc\xa7", U"a\u0327\u0323\u0302\u0308" }, // Vietnamese: ậ <U+1EAD> + diaeresis + cedilla = a + <U+0323> + <U+0302> = a + cedilla + dot below + circumflex + diaeresis
		
		// Non-BMP stuff:
		{ "\xf0\x9d\x85\xa0", U"\U0001D158\U0001D165\U0001D16E"}, // <U+1D160> MUSICAL SYMBOL EIGHTH NOTE
		{ "\xf0\xaf\xa0\xb4", U"\U00020A2C"}, // <U+2F834> -> <U+20A2C>
		
		// complex canonical ordering tests from Unicode's NormalizationTest.txt
		{ "x\xcc\x95\xcc\x80\xd6\xae\xcc\x80y", U"x\u05AE\u0300\u0300\u0315y" }, // "a" <U+0315><U+0300><U+05AE><U+0300> "b"  --> "a" <U+05AE><U+0300><U+0300><U+0315> "b"
		
		{ std::string(nullo, nullo+1), std::u32string(nullo32, nullo32+1) },  // Yeah, 1 NUL byte
		{ std::string(nullo, nullo+4), std::u32string(nullo32, nullo32+4) },  // Yeah, 4 NUL bytes
		
		{ "EOF", U"EOF" }
	};

}

class DecomposeTest : public ::testing::TestWithParam<TestEntry>
{
	// intentionally left blank for now.
};

INSTANTIATE_TEST_CASE_P(DecomposeTestInstance, DecomposeTest, testing::ValuesIn(testValues) );

TEST_P( DecomposeTest, Meh )
{
	const auto v = GetParam();
	EXPECT_EQ( v.output, fromUtf8_decompose(v.input) );
}