Everywhere: Hoist the Libraries folder to the top-level

Author: https://github.com/trflynn89
Commit: 93712b24bf
Pull-request: https://github.com/LadybirdBrowser/ladybird/pull/2256
Reviewed-by: https://github.com/sideshowbarker

Libraries/LibLine/XtermSuggestionDisplay.cpp

@@ -0,0 +1,195 @@
+/*
+ * Copyright (c) 2020-2021, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/BinarySearch.h>
+#include <AK/Function.h>
+#include <AK/StringBuilder.h>
+#include <LibCore/File.h>
+#include <LibLine/SuggestionDisplay.h>
+#include <LibLine/VT.h>
+#include <stdio.h>
+
+namespace Line {
+
+ErrorOr<void> XtermSuggestionDisplay::display(SuggestionManager const& manager)
+{
+    did_display();
+
+    auto stderr_stream = TRY(Core::File::standard_error());
+
+    size_t longest_suggestion_length = 0;
+    size_t longest_suggestion_byte_length = 0;
+    size_t longest_suggestion_byte_length_without_trivia = 0;
+
+    manager.set_start_index(0);
+    TRY(manager.for_each_suggestion([&](auto& suggestion, auto) {
+        longest_suggestion_length = max(longest_suggestion_length, suggestion.text_view().length() + suggestion.display_trivia_view().length());
+        longest_suggestion_byte_length = max(longest_suggestion_byte_length, suggestion.text_string().length() + suggestion.display_trivia_string().length());
+        longest_suggestion_byte_length_without_trivia = max(longest_suggestion_byte_length_without_trivia, suggestion.text_string().length());
+        return IterationDecision::Continue;
+    }));
+
+    size_t num_printed = 0;
+    size_t lines_used = 1;
+
+    TRY(VT::save_cursor(*stderr_stream));
+    TRY(VT::clear_lines(0, m_lines_used_for_last_suggestions, *stderr_stream));
+    TRY(VT::restore_cursor(*stderr_stream));
+
+    auto spans_entire_line { false };
+    Vector<StringMetrics::LineMetrics> lines;
+    for (size_t i = 0; i < m_prompt_lines_at_suggestion_initiation - 1; ++i)
+        lines.append({ {}, 0 });
+    lines.append({ {}, longest_suggestion_length });
+    auto max_line_count = StringMetrics { move(lines) }.lines_with_addition({ { { {}, 0 } } }, m_num_columns);
+    if (longest_suggestion_length >= m_num_columns - 2) {
+        spans_entire_line = true;
+        // We should make enough space for the biggest entry in
+        // the suggestion list to fit in the prompt line.
+        auto start = max_line_count - m_prompt_lines_at_suggestion_initiation;
+        for (size_t i = start; i < max_line_count; ++i)
+            TRY(stderr_stream->write_until_depleted("\n"sv.bytes()));
+        lines_used += max_line_count;
+        longest_suggestion_length = 0;
+    }
+
+    TRY(VT::move_absolute(max_line_count + m_origin_row, 1, *stderr_stream));
+
+    if (m_pages.is_empty()) {
+        size_t num_printed = 0;
+        size_t lines_used = 1;
+        // Cache the pages.
+        manager.set_start_index(0);
+        size_t page_start = 0;
+        TRY(manager.for_each_suggestion([&](auto& suggestion, auto index) {
+            size_t next_column = num_printed + suggestion.text_view().length() + longest_suggestion_length + 2;
+            if (next_column > m_num_columns) {
+                auto lines = (suggestion.text_view().length() + m_num_columns - 1) / m_num_columns;
+                lines_used += lines;
+                num_printed = 0;
+            }
+
+            if (lines_used + m_prompt_lines_at_suggestion_initiation >= m_num_lines) {
+                m_pages.append({ page_start, index });
+                page_start = index;
+                lines_used = 1;
+                num_printed = 0;
+            }
+
+            if (spans_entire_line)
+                num_printed += m_num_columns;
+            else
+                num_printed += longest_suggestion_length + 2;
+
+            return IterationDecision::Continue;
+        }));
+        // Append the last page.
+        m_pages.append({ page_start, manager.count() });
+    }
+
+    auto page_index = fit_to_page_boundary(manager.next_index());
+
+    manager.set_start_index(m_pages[page_index].start);
+    TRY(manager.for_each_suggestion([&](auto& suggestion, auto index) -> ErrorOr<IterationDecision> {
+        size_t next_column = num_printed + suggestion.text_view().length() + longest_suggestion_length + 2;
+
+        if (next_column > m_num_columns) {
+            auto lines = (suggestion.text_view().length() + m_num_columns - 1) / m_num_columns;
+            lines_used += lines;
+            TRY(stderr_stream->write_until_depleted("\n"sv.bytes()));
+            num_printed = 0;
+        }
+
+        // Show just enough suggestions to fill up the screen
+        // without moving the prompt out of view.
+        if (lines_used + m_prompt_lines_at_suggestion_initiation >= m_num_lines)
+            return IterationDecision::Break;
+
+        // Only apply color to the selection if something is *actually* added to the buffer.
+        if (manager.is_current_suggestion_complete() && index == manager.next_index()) {
+            TRY(VT::apply_style({ Style::Foreground(Style::XtermColor::Blue) }, *stderr_stream));
+        }
+
+        if (spans_entire_line) {
+            num_printed += m_num_columns;
+            TRY(stderr_stream->write_until_depleted(suggestion.text_string().bytes()));
+            TRY(stderr_stream->write_until_depleted(suggestion.display_trivia_string().bytes()));
+        } else {
+            auto field = ByteString::formatted("{: <{}}  {}", suggestion.text_string(), longest_suggestion_byte_length_without_trivia, suggestion.display_trivia_string());
+            TRY(stderr_stream->write_until_depleted(ByteString::formatted("{: <{}}", field, longest_suggestion_byte_length + 2)));
+            num_printed += longest_suggestion_length + 2;
+        }
+
+        if (manager.is_current_suggestion_complete() && index == manager.next_index())
+            TRY(VT::apply_style(Style::reset_style(), *stderr_stream));
+        return IterationDecision::Continue;
+    }));
+
+    m_lines_used_for_last_suggestions = lines_used;
+
+    // The last line of the prompt is the same line as the first line of the buffer, so we need to subtract one here.
+    lines_used += m_prompt_lines_at_suggestion_initiation - 1;
+
+    // If we filled the screen, move back the origin.
+    if (m_origin_row + lines_used >= m_num_lines) {
+        m_origin_row = m_num_lines - lines_used;
+    }
+
+    if (m_pages.size() > 1) {
+        auto left_arrow = page_index > 0 ? '<' : ' ';
+        auto right_arrow = page_index < m_pages.size() - 1 ? '>' : ' ';
+        auto string = ByteString::formatted("{:c} page {} of {} {:c}", left_arrow, page_index + 1, m_pages.size(), right_arrow);
+
+        if (string.length() > m_num_columns - 1) {
+            // This would overflow into the next line, so just don't print an indicator.
+            return {};
+        }
+
+        TRY(VT::move_absolute(m_origin_row + lines_used, m_num_columns - string.length() - 1, *stderr_stream));
+        TRY(VT::apply_style({ Style::Background(Style::XtermColor::Green) }, *stderr_stream));
+        TRY(stderr_stream->write_until_depleted(string.bytes()));
+        TRY(VT::apply_style(Style::reset_style(), *stderr_stream));
+    }
+
+    return {};
+}
+
+ErrorOr<bool> XtermSuggestionDisplay::cleanup()
+{
+    did_cleanup();
+
+    if (m_lines_used_for_last_suggestions) {
+        auto stderr_stream = TRY(Core::File::standard_error());
+        TRY(VT::clear_lines(0, m_lines_used_for_last_suggestions, *stderr_stream));
+        m_lines_used_for_last_suggestions = 0;
+        return true;
+    }
+
+    return false;
+}
+
+size_t XtermSuggestionDisplay::fit_to_page_boundary(size_t selection_index)
+{
+    VERIFY(m_pages.size() > 0);
+    size_t index = 0;
+
+    auto* match = binary_search(
+        m_pages.span(),
+        PageRange { selection_index, selection_index },
+        &index,
+        [](auto& a, auto& b) -> int {
+            if (a.start >= b.start && a.start < b.end)
+                return 0;
+            return a.start - b.start;
+        });
+
+    if (!match)
+        return m_pages.size() - 1;
+
+    return index;
+}
+
+}