/**
* Retrieve the header for this table. If border for this table is disabled, header will only be a
* row that contains column's caption. If border is enabled, the header is three lines with CP347
* pseudo-graphic characters to simulate a border.
*
* @return the definition of header.
*/
public TextLine[] getHeader() {
if (header == null) {
List<TextLine> tmp = new ArrayList<>();
StringBuilder line = new StringBuilder();
// draw header upper border if necessary
if (isDrawBorder()) {
line.append(EscpUtil.CP347_LIGHT_DOWN_RIGHT);
for (int columnIndex = 0; columnIndex < columns.size(); columnIndex++) {
TableColumn column = columns.get(columnIndex);
for (int i = 0; i < column.getWidth() - 1; i++) {
line.append(EscpUtil.CP347_LIGHT_HORIZONTAL);
}
if (columnIndex == (columns.size() - 1)) {
line.append(EscpUtil.CP347_LIGHT_DOWN_LEFT);
} else {
line.append(EscpUtil.CP347_LIGHT_DOWN_HORIZONTAL);
}
}
tmp.add(new TextLine(line.toString()));
}
// draw column name
line = new StringBuilder();
if (isDrawBorder()) {
line.append(EscpUtil.CP347_LIGHT_VERTICAL);
}
for (int columnIndex = 0; columnIndex < columns.size(); columnIndex++) {
TableColumn column = columns.get(columnIndex);
int width = column.getWidth() - (isDrawBorder() ? 1 : 0);
StringUtil.ALIGNMENT alignment = (new BasicPlaceholder(column.getText())).getAlignment();
if (alignment == null) {
alignment = StringUtil.ALIGNMENT.LEFT;
}
line.append(StringUtil.align(column.getCaption(), width, alignment));
if (isDrawBorder()) {
line.append(EscpUtil.CP347_LIGHT_VERTICAL);
}
}
tmp.add(new TextLine(line.toString()));
// draw lower border if necessary
line = new StringBuilder();
if (isDrawBorder()) {
line.append(EscpUtil.CP347_LIGHT_VERTICAL_RIGHT);
for (int columnIndex = 0; columnIndex < columns.size(); columnIndex++) {
TableColumn column = columns.get(columnIndex);
for (int i = 0; i < column.getWidth() - 1; i++) {
line.append(EscpUtil.CP347_LIGHT_HORIZONTAL);
}
if (columnIndex == (columns.size() - 1)) {
line.append(EscpUtil.CP347_LIGHT_VERTICAL_LEFT);
} else {
line.append(EscpUtil.CP347_LIGHT_VERTICAL_HORIZONTAL);
}
}
tmp.add(new TextLine(line.toString()));
}
header = tmp.toArray(new TextLine[0]);
}
return Arrays.copyOf(header, header.length);
}
