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/SuggestionManager.cpp

@@ -0,0 +1,187 @@
+/*
+ * Copyright (c) 2020, the SerenityOS developers.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+
+#include <AK/Assertions.h>
+#include <AK/Function.h>
+#include <LibLine/SuggestionManager.h>
+
+namespace Line {
+
+CompletionSuggestion::CompletionSuggestion(StringView completion, StringView trailing_trivia, StringView display_trivia, Style style)
+    : text(MUST(String::from_utf8(completion)))
+    , trailing_trivia(MUST(String::from_utf8(trailing_trivia)))
+    , display_trivia(MUST(String::from_utf8(display_trivia)))
+    , style(style)
+    , is_valid(true)
+{
+}
+
+void SuggestionManager::set_suggestions(Vector<CompletionSuggestion>&& suggestions)
+{
+    auto code_point_at = [](Utf8View view, size_t index) {
+        size_t count = 0;
+        for (auto cp : view) {
+            if (count == index) {
+                return cp;
+            }
+            count++;
+        }
+        VERIFY_NOT_REACHED();
+    };
+
+    m_suggestions = move(suggestions);
+
+    size_t common_suggestion_prefix { 0 };
+    if (m_suggestions.size() == 1) {
+        m_largest_common_suggestion_prefix_length = m_suggestions[0].text_view().length();
+    } else if (m_suggestions.size()) {
+        u32 last_valid_suggestion_code_point;
+
+        for (;; ++common_suggestion_prefix) {
+            if (m_suggestions[0].text_view().length() <= common_suggestion_prefix)
+                goto no_more_commons;
+
+            last_valid_suggestion_code_point = code_point_at(m_suggestions[0].text_view(), common_suggestion_prefix);
+
+            for (auto& suggestion : m_suggestions) {
+                if (suggestion.text_view().length() <= common_suggestion_prefix || code_point_at(suggestion.text_view(), common_suggestion_prefix) != last_valid_suggestion_code_point) {
+                    goto no_more_commons;
+                }
+            }
+        }
+    no_more_commons:;
+        m_largest_common_suggestion_prefix_length = common_suggestion_prefix;
+    } else {
+        m_largest_common_suggestion_prefix_length = 0;
+    }
+}
+
+void SuggestionManager::next()
+{
+    if (m_suggestions.size())
+        m_next_suggestion_index = (m_next_suggestion_index + 1) % m_suggestions.size();
+    else
+        m_next_suggestion_index = 0;
+}
+
+void SuggestionManager::previous()
+{
+    if (m_next_suggestion_index == 0)
+        m_next_suggestion_index = m_suggestions.size();
+    m_next_suggestion_index--;
+}
+
+CompletionSuggestion const& SuggestionManager::suggest()
+{
+    auto const& suggestion = m_suggestions[m_next_suggestion_index];
+    m_selected_suggestion_index = m_next_suggestion_index;
+    m_last_shown_suggestion = suggestion;
+    return suggestion;
+}
+
+void SuggestionManager::set_current_suggestion_initiation_index(size_t index)
+{
+    auto& suggestion = m_suggestions[m_next_suggestion_index];
+
+    if (m_last_shown_suggestion_display_length)
+        m_last_shown_suggestion.start_index = index - suggestion.static_offset - m_last_shown_suggestion_display_length;
+    else
+        m_last_shown_suggestion.start_index = index - suggestion.static_offset - suggestion.invariant_offset;
+
+    m_last_shown_suggestion_display_length = m_last_shown_suggestion.text_view().length();
+    m_last_shown_suggestion_was_complete = true;
+}
+
+SuggestionManager::CompletionAttemptResult SuggestionManager::attempt_completion(CompletionMode mode, size_t initiation_start_index)
+{
+    CompletionAttemptResult result { mode };
+
+    if (m_next_suggestion_index < m_suggestions.size()) {
+        auto& next_suggestion = m_suggestions[m_next_suggestion_index];
+
+        if (mode == CompletePrefix && !next_suggestion.allow_commit_without_listing) {
+            result.new_completion_mode = CompletionMode::ShowSuggestions;
+            result.avoid_committing_to_single_suggestion = true;
+            m_last_shown_suggestion_display_length = 0;
+            m_last_shown_suggestion_was_complete = false;
+            m_last_shown_suggestion = ByteString::empty();
+            return result;
+        }
+
+        auto can_complete = next_suggestion.invariant_offset <= m_largest_common_suggestion_prefix_length;
+        ssize_t actual_offset;
+        size_t shown_length = m_last_shown_suggestion_display_length;
+        switch (mode) {
+        case CompletePrefix:
+            actual_offset = 0;
+            break;
+        case ShowSuggestions:
+            actual_offset = 0 - m_largest_common_suggestion_prefix_length + next_suggestion.invariant_offset;
+            if (can_complete && next_suggestion.allow_commit_without_listing)
+                shown_length = m_largest_common_suggestion_prefix_length + m_last_shown_suggestion.trivia_view().length();
+            break;
+        default:
+            if (m_last_shown_suggestion_display_length == 0)
+                actual_offset = 0;
+            else
+                actual_offset = 0 - m_last_shown_suggestion_display_length + next_suggestion.invariant_offset;
+            break;
+        }
+
+        auto& suggestion = suggest();
+        set_current_suggestion_initiation_index(initiation_start_index);
+
+        result.offset_region_to_remove = { next_suggestion.invariant_offset, shown_length };
+        result.new_cursor_offset = actual_offset;
+        result.static_offset_from_cursor = next_suggestion.static_offset;
+
+        if (mode == CompletePrefix) {
+            // Only auto-complete *if possible*.
+            if (can_complete) {
+                result.insert.append(suggestion.text_view().unicode_substring_view(suggestion.invariant_offset, m_largest_common_suggestion_prefix_length - suggestion.invariant_offset));
+                m_last_shown_suggestion_display_length = m_largest_common_suggestion_prefix_length;
+                // Do not increment the suggestion index, as the first tab should only be a *peek*.
+                if (m_suggestions.size() == 1) {
+                    // If there's one suggestion, commit and forget.
+                    result.new_completion_mode = DontComplete;
+                    // Add in the trivia of the last selected suggestion.
+                    result.insert.append(suggestion.trailing_trivia.code_points());
+                    m_last_shown_suggestion_display_length = 0;
+                    result.style_to_apply = suggestion.style;
+                    m_last_shown_suggestion_was_complete = true;
+                    return result;
+                }
+            } else {
+                m_last_shown_suggestion_display_length = 0;
+            }
+            result.new_completion_mode = CompletionMode::ShowSuggestions;
+            m_last_shown_suggestion_was_complete = false;
+            m_last_shown_suggestion = ByteString::empty();
+        } else {
+            result.insert.append(suggestion.text_view().unicode_substring_view(suggestion.invariant_offset, suggestion.text_view().length() - suggestion.invariant_offset));
+            // Add in the trivia of the last selected suggestion.
+            result.insert.append(suggestion.trailing_trivia.code_points());
+            m_last_shown_suggestion_display_length += suggestion.trivia_view().length();
+        }
+    } else {
+        m_next_suggestion_index = 0;
+    }
+    return result;
+}
+
+ErrorOr<size_t> SuggestionManager::for_each_suggestion(Function<ErrorOr<IterationDecision>(CompletionSuggestion const&, size_t)> callback) const
+{
+    size_t start_index { 0 };
+    for (auto& suggestion : m_suggestions) {
+        if (start_index++ < m_last_displayed_suggestion_index)
+            continue;
+        if (TRY(callback(suggestion, start_index - 1)) == IterationDecision::Break)
+            break;
+    }
+    return start_index;
+}
+
+}