#include "stdafx.h"
#include "LogEdit.h"


#define MENU_ITEM_SEL_ALL		0x666
#define MENU_ITEM_COPY			0x667
#define MENU_ITEM_CLEAR			0x668

CLogEdit::CLogEdit()
{
	m_nMaxLines = 0xffff;
	m_nTrimLines = 100;
	m_bAutoScroll = TRUE;
}


CLogEdit::~CLogEdit()
{
}

BEGIN_MESSAGE_MAP(CLogEdit, CEdit)
	ON_WM_CONTEXTMENU()
	ON_WM_VSCROLL()
END_MESSAGE_MAP()

void CLogEdit::SetMaxLineCount(int line)
{
	m_nMaxLines = line;
	m_nTrimLines = min(m_nMaxLines, 100);
}

void CLogEdit::OnContextMenu(CWnd* pWnd, CPoint point)
{
	HMENU hMenu = CreatePopupMenu();
	InsertMenu(hMenu, 0, MF_BYPOSITION, MENU_ITEM_SEL_ALL, "È«Ñ¡");
	InsertMenu(hMenu, 1, MF_BYPOSITION, MENU_ITEM_COPY, "¸´ÖÆ");
	InsertMenu(hMenu, 2, MF_BYPOSITION | MF_SEPARATOR, NULL, NULL);	
	InsertMenu(hMenu, 3, MF_BYPOSITION, MENU_ITEM_CLEAR, "È«²¿Çå³ý");
	int cmd = ::TrackPopupMenu(hMenu,
		TPM_LEFTALIGN | TPM_RIGHTBUTTON | TPM_RETURNCMD,
		point.x, point.y + 2, 0, m_hWnd, NULL);
	DestroyMenu(hMenu);

	if (cmd == MENU_ITEM_SEL_ALL) {
		SetFocus();
		this->SetSel(0, -1);
	}
	else if (cmd == MENU_ITEM_COPY) {
		this->Copy();
	}
	else if (cmd == MENU_ITEM_CLEAR) {
		SetWindowText(_T(""));
	}
}

void CLogEdit::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar)
{
	// ÿ´Î¹ö¶¯Ê±¼ì²éÊÇ·ñ»¹Ôڵײ¿
	m_bAutoScroll = IsScrollBarAtBottom();
	CEdit::OnVScroll(nSBCode, nPos, pScrollBar);
}

BOOL CLogEdit::IsScrollBarAtBottom()
{
	SCROLLINFO si = { sizeof(si), SIF_ALL };
	GetScrollInfo(SB_VERT, &si);
	return (si.nPos + (int)si.nPage >= si.nMax);
}

void CLogEdit::AppendText(const char* pszText)
{
	SetRedraw(FALSE);

	// ²Ã¼ôÂß¼­
	int totalLines = GetLineCount();
	if (totalLines > m_nMaxLines) {
		// »ñȡҪɾ³ýµÄ×Ö·û·¶Î§
		int startChar = LineIndex(0);			// µÚ0ÐÐÊ××Ö·ûλÖÃ
		int endChar = LineIndex(m_nTrimLines);	// µÚNÐÐÊ××Ö·ûλÖÃ

		if (startChar >= 0 && endChar > startChar) {
			SetSel(startChar, endChar);
			ReplaceSel(_T("")); // ɾ³ýÇ°ÃæÐÐ
		}
	}


	int len = GetWindowTextLength();
	SetSel(len, len);
	ReplaceSel(pszText);

	if (m_bAutoScroll) {
		LineScroll(GetLineCount());
	}

	SetRedraw(TRUE);
	Invalidate();
	UpdateWindow();
}