/// <summary>
/// return the ContentField with a textbyte that covers the specified rowcol
/// location.
/// </summary>
/// <param name="ix"></param>
/// <returns></returns>
public ContentField GetContentField(IRowCol RowCol)
{
ContentField getField = null;
int ix = ToContentIndex(RowCol);
// look prior to the location, looking for that closest field.
while (ix > 0)
{
ix -= 1;
var textByte = this.ContentArray[ix];
if (textByte.IsAttrByte( ))
{
ContentItemBase contentItem = null;
var rowCol = ix.ToZeroRowCol(this.ScreenDim);
var rc = this.FieldDict.TryGetValue(rowCol, out contentItem);
// attr byte is start of a field.
if ((rc == true) && (contentItem is ContentField))
{
var field = contentItem as ContentField;
var fieldRange = new RowColRange(field.RowCol.AdvanceRight( ), field.LL_Length);
if (fieldRange.Contains(RowCol))
{
getField = field;
break;
}
}
}
}
return(getField);
}
public static ContentItemBase GetContentItem(this ScreenContent Content, IScreenLoc loc)
{
ContentItemBase foundItem = null;
foreach (var contentItem in Content.ContentItems())
{
var itemLoc = contentItem.RowCol as IScreenLoc;
var range = new ScreenLocRange(
itemLoc, contentItem.GetItemLength(Content), Content.ScreenDim);
if (range.Contains(loc))
{
foundItem = contentItem;
break;
}
}
return(foundItem);
}
/// <summary>
/// return the sequence of fields that start within the rowcol range of the
/// content table.
/// </summary>
/// <param name="Range"></param>
/// <returns></returns>
public IEnumerable <ContentField> ContentFields(RowColRange Range)
{
int ix = 0;
ContentItemBase contentItem = null;
foreach (var b1 in ContentBytes(Range))
{
if (b1.IsAttrByte( ))
{
var rowCol = Range.From.Advance(ix) as ZeroRowCol;
var rc = this.FieldDict.TryGetValue(rowCol, out contentItem);
if ((rc == true) && (contentItem is ContentField))
{
yield return(contentItem as ContentField);
}
}
ix += 1;
}
yield break;
}
public IEnumerable <ContentItemBase> ContentItems()
{
int ix = -1;
var blankBytes = new byte[] { 0x00, 0x40 };
while (true)
{
ix += 1;
if (ix >= this.ContentArray.Length)
{
break;
}
// advance to next non blank.
ix = this.ContentArray.IndexOfNotEqual(ix, blankBytes);
if (ix == -1)
{
break;
}
var curByte = this.ContentArray[ix];
// not an attribute byte. process bytes up until an attr byte as
// ContentText.
if (curByte.IsAttrByte() == false)
{
var bx = ix;
var rv = ContentArray_ScanUntilAttrByte(ix);
var textBuf = rv.Item1;
var abIx = rv.Item2;
if (textBuf.Length > 0)
{
// only if the text bytes are not all blanks.
var fx = textBuf.IndexOfNotEqual(0, blankBytes);
if (fx != -1)
{
var rowcol = ix.ToZeroRowCol(this.ScreenDim);
var contentText = new ContentText(rowcol, null, textBuf.Length, null);
yield return(contentText);
}
}
// setup ix for next iteration of the loop.
if (abIx == -1)
{
ix = this.ContentArray.Length;
}
else
{
ix = abIx - 1;
}
continue;
}
// Got attr byte. Check that start of a field defined in the FieldDict.
{
ContentItemBase contentItem = null;
var rowCol = ix.ToZeroRowCol(this.ScreenDim);
var rc = this.FieldDict.TryGetValue(rowCol, out contentItem);
// attr byte is start of a field.
if ((rc == true) && (contentItem is ContentField))
{
var contentField = contentItem as ContentField;
contentField.LoadContents(this);
ix += 1; // advance past attr byte.
ix = (ix + contentField.LL_Length) - 1;
yield return(contentField);
continue;
}
}
// attribute byte is not a field. Look for whitespace immed after the attr
// byte.
{
var abIx = ix;
if (curByte == 0x20)
{
var fx = this.ContentArray.IndexOfNotEqual(ix + 1, blankBytes);
// nothing but whitespace after the attr byte. Setup ix so next iter will
// be EOF.
if (fx == -1)
{
ix = this.ContentArray.Length;
continue;
}
// blanks until another attr byte. skip the current attr and the
// whitespace that follows.
else if (this.ContentArray[fx].IsAttrByte() == true)
{
ix = fx - 1;
continue;
}
}
// got a text char to display as ContentText.
{
int textStart = abIx + 1;
var rv = ContentArray_ScanUntilAttrByte(textStart);
var rowCol = abIx.ToZeroRowCol(this.ScreenDim);
var textLength = rv.Item1.Length;
// the end of content text attr byte is x'20'. Treat as tail attr byte.
int?tailAttrByteIx = null;
int nextIx = rv.Item2;
if ((nextIx != -1) && (rv.Item3 == 0x20))
{
var nextByte = ContentArray_NextNonZeroByte(nextIx + 1);
if ((nextByte == null) || (nextByte.Value.IsAttrByte( ) == true))
{
tailAttrByteIx = nextIx;
nextIx += 1;
}
}
// no attribute found. trim blanks from byte buffer.
if (nextIx == -1)
{
var byteBuf = rv.Item1;
var fx = byteBuf.IndexOfLastNotEqual(blankBytes);
if (fx == -1)
{
textLength = 0;
}
else
{
textLength = fx + 1;
}
}
// return the text constant.
var contentText = new ContentText(
rowCol, this.ContentArray[abIx], textLength, tailAttrByteIx);
yield return(contentText);
if (nextIx == -1)
{
break;
}
ix = nextIx - 1;
}
}
}
yield break;
}