Intermediate changes

commit_hash:5fc851d2c72810067fe0d407b66535b17de63129

1 files changed, 89 insertions, 0 deletions

diff --git a/yql/essentials/sql/v1/complete/sql_complete.cpp b/yql/essentials/sql/v1/complete/sql_complete.cpp
new file mode 100644
index 00000000000..2a16a250e54
--- /dev/null
+++ b/yql/essentials/sql/v1/complete/sql_complete.cpp
@@ -0,0 +1,89 @@
+#include "sql_complete.h"
+
+#include "sql_context.h"
+#include "string_util.h"
+
+#include <util/generic/algorithm.h>
+#include <util/charset/utf8.h>
+
+namespace NSQLComplete {
+
+    class TSqlCompletionEngine: public ISqlCompletionEngine {
+    public:
+        TSqlCompletionEngine()
+            : ContextInference(MakeSqlContextInference())
+        {
+        }
+
+        TCompletion Complete(TCompletionInput input) {
+            auto prefix = input.Text.Head(input.CursorPosition);
+            auto completedToken = GetCompletedToken(prefix);
+
+            auto context = ContextInference->Analyze(input);
+
+            TVector<TCandidate> candidates;
+            EnrichWithKeywords(candidates, context.Keywords);
+
+            FilterByContent(candidates, completedToken.Content);
+
+            RankingSort(candidates);
+
+            return {
+                .CompletedToken = std::move(completedToken),
+                .Candidates = std::move(candidates),
+            };
+        }
+
+    private:
+        TCompletedToken GetCompletedToken(TStringBuf prefix) {
+            return {
+                .Content = LastWord(prefix),
+                .SourcePosition = LastWordIndex(prefix),
+            };
+        }
+
+        void EnrichWithKeywords(TVector<TCandidate>& candidates, TVector<TString> keywords) {
+            for (auto keyword : keywords) {
+                candidates.push_back({
+                    .Kind = ECandidateKind::Keyword,
+                    .Content = std::move(keyword),
+                });
+            }
+        }
+
+        void FilterByContent(TVector<TCandidate>& candidates, TStringBuf prefix) {
+            const auto lowerPrefix = ToLowerUTF8(prefix);
+            auto removed = std::ranges::remove_if(candidates, [&](const auto& candidate) {
+                return !ToLowerUTF8(candidate.Content).StartsWith(lowerPrefix);
+            });
+            candidates.erase(std::begin(removed), std::end(removed));
+        }
+
+        void RankingSort(TVector<TCandidate>& candidates) {
+            Sort(candidates, [](const TCandidate& lhs, const TCandidate& rhs) {
+                return std::tie(lhs.Kind, lhs.Content) < std::tie(rhs.Kind, rhs.Content);
+            });
+        }
+
+        ISqlContextInference::TPtr ContextInference;
+    };
+
+    ISqlCompletionEngine::TPtr MakeSqlCompletionEngine() {
+        return ISqlCompletionEngine::TPtr(new TSqlCompletionEngine());
+    }
+
+} // namespace NSQLComplete
+
+template <>
+void Out<NSQLComplete::ECandidateKind>(IOutputStream& out, NSQLComplete::ECandidateKind kind) {
+    switch (kind) {
+        case NSQLComplete::ECandidateKind::Keyword:
+            out << "Keyword";
+            break;
+    }
+}
+
+template <>
+void Out<NSQLComplete::TCandidate>(IOutputStream& out, const NSQLComplete::TCandidate& candidate) {
+    out << "(" << candidate.Kind << ": " << candidate.Content << ")";
+}