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+// Copyright 2012 The Kyua Authors.
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+// * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+// * Redistributions in binary form must reproduce the above copyright
+// notice, this list of conditions and the following disclaimer in the
+// documentation and/or other materials provided with the distribution.
+// * Neither the name of Google Inc. nor the names of its contributors
+// may be used to endorse or promote products derived from this software
+// without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+#include "utils/text/table.hpp"
+
+#include <algorithm>
+#include <iterator>
+#include <limits>
+#include <sstream>
+
+#include "utils/sanity.hpp"
+#include "utils/text/operations.ipp"
+
+namespace text = utils::text;
+
+
+namespace {
+
+
+/// Applies user overrides to the column widths of a table.
+///
+/// \param table The table from which to calculate the column widths.
+/// \param user_widths The column widths provided by the user. This vector must
+/// have less or the same number of elements as the columns of the table.
+/// Values of width_auto are ignored; any other explicit values are copied
+/// to the output widths vector, including width_refill.
+///
+/// \return A vector with the widths of the columns of the input table with any
+/// user overrides applied.
+static text::widths_vector
+override_column_widths(const text::table& table,
+ const text::widths_vector& user_widths)
+{
+ PRE(user_widths.size() <= table.ncolumns());
+ text::widths_vector widths = table.column_widths();
+
+ // Override the actual width of the columns based on user-specified widths.
+ for (text::widths_vector::size_type i = 0; i < user_widths.size(); ++i) {
+ const text::widths_vector::value_type& user_width = user_widths[i];
+ if (user_width != text::table_formatter::width_auto) {
+ PRE_MSG(user_width == text::table_formatter::width_refill ||
+ user_width >= widths[i],
+ "User-provided column widths must be larger than the "
+ "column contents (except for the width_refill column)");
+ widths[i] = user_width;
+ }
+ }
+
+ return widths;
+}
+
+
+/// Locates the refill column, if any.
+///
+/// \param widths The widths of the columns as returned by
+/// override_column_widths(). Note that one of the columns may or may not
+/// be width_refill, which is the column we are looking for.
+///
+/// \return The index of the refill column with a width_refill width if any, or
+/// otherwise the index of the last column (which is the default refill column).
+static text::widths_vector::size_type
+find_refill_column(const text::widths_vector& widths)
+{
+ text::widths_vector::size_type i = 0;
+ for (; i < widths.size(); ++i) {
+ if (widths[i] == text::table_formatter::width_refill)
+ return i;
+ }
+ return i - 1;
+}
+
+
+/// Pads the widths of the table to fit within a maximum width.
+///
+/// On output, a column of the widths vector is truncated to a shorter length
+/// than its current value, if the total width of the table would exceed the
+/// maximum table width.
+///
+/// \param [in,out] widths The widths of the columns as returned by
+/// override_column_widths(). One of these columns should have a value of
+/// width_refill; if not, a default column is refilled.
+/// \param user_max_width The target width of the table; must not be zero.
+/// \param column_padding The padding between the cells, if any. The target
+/// width should be larger than the padding times the number of columns; if
+/// that is not the case, we attempt a readjustment here.
+static void
+refill_widths(text::widths_vector& widths,
+ const text::widths_vector::value_type user_max_width,
+ const std::size_t column_padding)
+{
+ PRE(user_max_width != 0);
+
+ // widths.size() is a proxy for the number of columns of the table.
+ const std::size_t total_padding = column_padding * (widths.size() - 1);
+ const text::widths_vector::value_type max_width = std::max(
+ user_max_width, total_padding) - total_padding;
+
+ const text::widths_vector::size_type refill_column =
+ find_refill_column(widths);
+ INV(refill_column < widths.size());
+
+ text::widths_vector::value_type width = 0;
+ for (text::widths_vector::size_type i = 0; i < widths.size(); ++i) {
+ if (i != refill_column)
+ width += widths[i];
+ }
+ widths[refill_column] = max_width - width;
+}
+
+
+/// Pads an input text to a specified width with spaces.
+///
+/// \param input The text to add padding to (may be empty).
+/// \param length The desired length of the output.
+/// \param is_last Whether the text being processed belongs to the last column
+/// of a row or not. Values in the last column should not be padded to
+/// prevent trailing whitespace on the screen (which affects copy/pasting
+/// for example).
+///
+/// \return The padded cell. If the input string is longer than the desired
+/// length, the input string is returned verbatim. The padded table won't be
+/// correct, but we don't expect this to be a common case to worry about.
+static std::string
+pad_cell(const std::string& input, const std::size_t length, const bool is_last)
+{
+ if (is_last)
+ return input;
+ else {
+ if (input.length() < length)
+ return input + std::string(length - input.length(), ' ');
+ else
+ return input;
+ }
+}
+
+
+/// Refills a cell and adds it to the output lines.
+///
+/// \param row The row containing the cell to be refilled.
+/// \param widths The widths of the row.
+/// \param column The column being refilled.
+/// \param [in,out] textual_rows The output lines as processed so far. This is
+/// updated to accomodate for the contents of the refilled cell, extending
+/// the rows as necessary.
+static void
+refill_cell(const text::table_row& row, const text::widths_vector& widths,
+ const text::table_row::size_type column,
+ std::vector< text::table_row >& textual_rows)
+{
+ const std::vector< std::string > rows = text::refill(row[column],
+ widths[column]);
+
+ if (textual_rows.size() < rows.size())
+ textual_rows.resize(rows.size(), text::table_row(row.size()));
+
+ for (std::vector< std::string >::size_type i = 0; i < rows.size(); ++i) {
+ for (text::table_row::size_type j = 0; j < row.size(); ++j) {
+ const bool is_last = j == row.size() - 1;
+ if (j == column)
+ textual_rows[i][j] = pad_cell(rows[i], widths[j], is_last);
+ else {
+ if (textual_rows[i][j].empty())
+ textual_rows[i][j] = pad_cell("", widths[j], is_last);
+ }
+ }
+ }
+}
+
+
+/// Formats a single table row.
+///
+/// \param row The row to format.
+/// \param widths The widths of the columns to apply during formatting. Cells
+/// wider than the specified width are refilled to attempt to fit in the
+/// cell. Cells narrower than the width are right-padded with spaces.
+/// \param separator The column separator to use.
+///
+/// \return The textual lines that contain the formatted row.
+static std::vector< std::string >
+format_row(const text::table_row& row, const text::widths_vector& widths,
+ const std::string& separator)
+{
+ PRE(row.size() == widths.size());
+
+ std::vector< text::table_row > textual_rows(1, text::table_row(row.size()));
+
+ for (text::table_row::size_type column = 0; column < row.size(); ++column) {
+ if (widths[column] > row[column].length())
+ textual_rows[0][column] = pad_cell(row[column], widths[column],
+ column == row.size() - 1);
+ else
+ refill_cell(row, widths, column, textual_rows);
+ }
+
+ std::vector< std::string > lines;
+ for (std::vector< text::table_row >::const_iterator
+ iter = textual_rows.begin(); iter != textual_rows.end(); ++iter) {
+ lines.push_back(text::join(*iter, separator));
+ }
+ return lines;
+}
+
+
+} // anonymous namespace
+
+
+/// Constructs a new table.
+///
+/// \param ncolumns_ The number of columns that the table will have.
+text::table::table(const table_row::size_type ncolumns_)
+{
+ _column_widths.resize(ncolumns_, 0);
+}
+
+
+/// Gets the number of columns in the table.
+///
+/// \return The number of columns in the table. This value remains constant
+/// during the existence of the table.
+text::widths_vector::size_type
+text::table::ncolumns(void) const
+{
+ return _column_widths.size();
+}
+
+
+/// Gets the width of a column.
+///
+/// The returned value is not valid if add_row() is called again, as the column
+/// may have grown in width.
+///
+/// \param column The index of the column of which to get the width. Must be
+/// less than the total number of columns.
+///
+/// \return The width of a column.
+text::widths_vector::value_type
+text::table::column_width(const widths_vector::size_type column) const
+{
+ PRE(column < _column_widths.size());
+ return _column_widths[column];
+}
+
+
+/// Gets the widths of all columns.
+///
+/// The returned value is not valid if add_row() is called again, as the columns
+/// may have grown in width.
+///
+/// \return A vector with the width of all columns.
+const text::widths_vector&
+text::table::column_widths(void) const
+{
+ return _column_widths;
+}
+
+
+/// Checks whether the table is empty or not.
+///
+/// \return True if the table is empty; false otherwise.
+bool
+text::table::empty(void) const
+{
+ return _rows.empty();
+}
+
+
+/// Adds a row to the table.
+///
+/// \param row The row to be added. This row must have the same amount of
+/// columns as defined during the construction of the table.
+void
+text::table::add_row(const table_row& row)
+{
+ PRE(row.size() == _column_widths.size());
+ _rows.push_back(row);
+
+ for (table_row::size_type i = 0; i < row.size(); ++i)
+ if (_column_widths[i] < row[i].length())
+ _column_widths[i] = row[i].length();
+}
+
+
+/// Gets an iterator pointing to the beginning of the rows of the table.
+///
+/// \return An iterator on the rows.
+text::table::const_iterator
+text::table::begin(void) const
+{
+ return _rows.begin();
+}
+
+
+/// Gets an iterator pointing to the end of the rows of the table.
+///
+/// \return An iterator on the rows.
+text::table::const_iterator
+text::table::end(void) const
+{
+ return _rows.end();
+}
+
+
+/// Column width to denote that the column has to fit all of its cells.
+const std::size_t text::table_formatter::width_auto = 0;
+
+
+/// Column width to denote that the column can be refilled to fit the table.
+const std::size_t text::table_formatter::width_refill =
+ std::numeric_limits< std::size_t >::max();
+
+
+/// Constructs a new table formatter.
+text::table_formatter::table_formatter(void) :
+ _separator(""),
+ _table_width(0)
+{
+}
+
+
+/// Sets the width of a column.
+///
+/// All columns except one must have a width that is, at least, as wide as the
+/// widest cell in the column. One of the columns can have a width of
+/// width_refill, which indicates that the column will be refilled if the table
+/// does not fit in its maximum width.
+///
+/// \param column The index of the column to set the width for.
+/// \param width The width to set the column to.
+///
+/// \return A reference to this formatter to allow using the builder pattern.
+text::table_formatter&
+text::table_formatter::set_column_width(const table_row::size_type column,
+ const std::size_t width)
+{
+#if !defined(NDEBUG)
+ if (width == width_refill) {
+ for (widths_vector::size_type i = 0; i < _column_widths.size(); i++) {
+ if (i != column)
+ PRE_MSG(_column_widths[i] != width_refill,
+ "Only one column width can be set to width_refill");
+ }
+ }
+#endif
+
+ if (_column_widths.size() < column + 1)
+ _column_widths.resize(column + 1, width_auto);
+ _column_widths[column] = width;
+ return *this;
+}
+
+
+/// Sets the separator to use between the cells.
+///
+/// \param separator The separator to use.
+///
+/// \return A reference to this formatter to allow using the builder pattern.
+text::table_formatter&
+text::table_formatter::set_separator(const char* separator)
+{
+ _separator = separator;
+ return *this;
+}
+
+
+/// Sets the maximum width of the table.
+///
+/// \param table_width The maximum width of the table; cannot be zero.
+///
+/// \return A reference to this formatter to allow using the builder pattern.
+text::table_formatter&
+text::table_formatter::set_table_width(const std::size_t table_width)
+{
+ PRE(table_width > 0);
+ _table_width = table_width;
+ return *this;
+}
+
+
+/// Formats a table into a collection of textual lines.
+///
+/// \param t Table to format.
+///
+/// \return A collection of textual lines.
+std::vector< std::string >
+text::table_formatter::format(const table& t) const
+{
+ std::vector< std::string > lines;
+
+ if (!t.empty()) {
+ widths_vector widths = override_column_widths(t, _column_widths);
+ if (_table_width != 0)
+ refill_widths(widths, _table_width, _separator.length());
+
+ for (table::const_iterator iter = t.begin(); iter != t.end(); ++iter) {
+ const std::vector< std::string > sublines =
+ format_row(*iter, widths, _separator);
+ std::copy(sublines.begin(), sublines.end(),
+ std::back_inserter(lines));
+ }
+ }
+
+ return lines;
+}