#include?“Editor.h“

#pragma?comment（lib“winmm.lib“）

namespace?{
	inline?bool?IsHighSurrogate（UINT32?ch）?throw（）
	{
		//?0xD800?<=?ch?<=?0xDBFF
		return?（ch?&?0xFC00）?==?0xD800;
	}

	inline?bool?IsLowSurrogate（UINT32?ch）?throw（）
	{
		//?0xDC00?<=?ch?<=?0xDFFF
		return?（ch?&?0xFC00）?==?0xDC00;
	}
}

Editor::Editor（）
{
	maxScrollY?=?0.f;
	scrollY?=?0.f;

	lastInputTime?=?-1.f;
	lastClickTime?=?-1.f;
	lastSelectLength?=?0;

	isonscroll?=?false;

	textLayout?=?nullptr;
	needUpdate?=?true;
	caretAnchor?=?0;
	caretPosition?=?0;
	text?=?L“helloworld?北冥有魚，其名為鯤。鯤之大，不知其幾千里也。化而為鳥，其名為鵬。鵬之背，不知其幾千里也。怒而飛，其翼若垂天之云。是鳥也，海運則將徙于南冥。南冥者，天池也。“;
}

Editor::~Editor（）
{
	SafeRelease（&textLayout）;
}


void?Editor::select（SelectMode?mode?bool?moveAnchor）
{
	//以下代碼使用了dwrite的api

	switch?（mode）
	{
	case?SelectMode::up:
	case?SelectMode::down:
	{
		std::vector?lineMetrics;
		DWRITE_TEXT_METRICS?textMetrics;
		textLayout->GetMetrics（&textMetrics）;

		lineMetrics.resize（textMetrics.lineCount）;
		textLayout->GetLineMetrics（&lineMetrics.front（）?textMetrics.lineCount?&textMetrics.lineCount）;


		UINT32?line?=?0;
		UINT32?linePosition?=?0;
		UINT32?nextLinePosition?=?0;
		UINT32?lineCount?=?static_cast（lineMetrics.size（））;
		for?（;?line?		{
			linePosition?=?nextLinePosition;
			nextLinePosition?=?linePosition?+?lineMetrics[line].length;
			if?（nextLinePosition?>?caretPosition）?{
				break;
			}
		}

		if?（line?>?lineCount?-?1）?{
			line?=?lineCount?-?1;
		}

		if?（mode?==?SelectMode::up）
		{
			if?（line?<=?0）
				break;
			line--;
			linePosition?-=?lineMetrics[line].length;
		}
		else
		{
			linePosition?+=?lineMetrics[line].length;
			line++;
			if?（line?>=?lineMetrics.size（））
				break;
		}

		DWRITE_HIT_TEST_METRICS?hitTestMetrics;
		float?caretX?caretY?dummyX;

		textLayout->HitTestTextPosition（
			caretPosition
			false
			&caretX
			&caretY
			&hitTestMetrics
		）;

		textLayout->HitTestTextPosition（
			linePosition
			false
			&dummyX
			&caretY
			&hitTestMetrics
		）;

		BOOL?isInside?isTrailingHit;
		textLayout->HitTestPoint（
			caretX
			caretY
			&isTrailingHit
			&isInside
			&hitTestMetrics
		）;

		caretPosition?=?hitTestMetrics.textPosition;

		if?（isTrailingHit）?{
			caretPosition?+=?hitTestMetrics.length;
		}
		break;
	}
	case?SelectMode::head:
		caretPosition?=?0;
		break;
	case?SelectMode::tile:
		caretPosition?=?text.length（）;
		break;
	case?SelectMode::lastChar:
		if?（caretPosition?>?0）?{
			UINT32?moveCount?=?1;

			if?（caretPosition?>=?2
				&&?caretPosition?<=?text.length（））
			{
				if?（isUnicodeUnit（text[caretPosition?-?1]?text[caretPosition?-?2]））
				{
					moveCount?=?2;
				}
			}
			if?（caretPosition?				caretPosition?=?0;
			else?caretPosition?-=?moveCount;
		}
		break;
	case?SelectMode::nextChar:
		if?（caretPositi

?屬性????????????大小?????日期????時間???名稱
-----------?---------??----------?-----??----
?????文件???????15399??2018-11-24?16:07??Editor.cpp
?????文件????????1924??2018-11-24?16:06??Editor.h
?????文件?????????258??2018-11-24?15:24??main.cpp
?????文件????????5096??2018-11-24?16:06??MyWindow.cpp
?????文件????????1360??2018-11-24?16:06??MyWindow.h
?????文件???????24064??2018-11-24?16:12??program.exe