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#include "column.h"
#include "base_visitor.h"
#include "narrowing_visitor.h"
#include <yql/essentials/sql/v1/complete/syntax/format.h>
namespace NSQLComplete {
namespace {
// TODO: Extract it to `identifier.cpp` and reuse it also at `use.cpp`
// and replace `GetId` at `parse_tree.cpp`.
class TIdentifierVisitor: public SQLv1Antlr4BaseVisitor {
public:
std::any visitCluster_expr(SQLv1::Cluster_exprContext* ctx) override {
if (auto* x = ctx->pure_column_or_named()) {
return visit(x);
}
return {};
}
std::any visitTable_key(SQLv1::Table_keyContext* ctx) override {
if (auto* x = ctx->id_table_or_type()) {
return visit(x);
}
return {};
}
std::any visitUnary_casual_subexpr(SQLv1::Unary_casual_subexprContext* ctx) override {
std::any prev;
if (auto* x = ctx->id_expr()) {
prev = visit(x);
} else if (auto* x = ctx->atom_expr()) {
prev = visit(x);
}
std::any next = visit(ctx->unary_subexpr_suffix());
if (!next.has_value()) {
return prev;
}
return {};
}
std::any visitTerminal(antlr4::tree::TerminalNode* node) override {
switch (node->getSymbol()->getType()) {
case SQLv1::TOKEN_ID_QUOTED:
return Unquoted(GetText(node));
case SQLv1::TOKEN_ID_PLAIN:
return GetText(node);
}
return {};
}
private:
TString GetText(antlr4::tree::ParseTree* tree) const {
return TString(tree->getText());
}
};
TMaybe<TString> GetId(antlr4::ParserRuleContext* ctx) {
if (ctx == nullptr) {
return Nothing();
}
std::any result = TIdentifierVisitor().visit(ctx);
if (!result.has_value()) {
return Nothing();
}
return std::any_cast<TString>(result);
}
class TInferenceVisitor: public TSQLv1BaseVisitor {
public:
std::any visitJoin_source(SQLv1::Join_sourceContext* ctx) override {
return AccumulatingVisit(ctx->flatten_source());
}
std::any visitNamed_single_source(SQLv1::Named_single_sourceContext* ctx) override {
SQLv1::Single_sourceContext* singleSource = ctx->single_source();
if (singleSource == nullptr) {
return {};
}
std::any any = visit(singleSource);
if (!any.has_value()) {
return {};
}
TColumnContext context = std::move(std::any_cast<TColumnContext>(any));
TMaybe<TString> alias = GetAlias(ctx);
if (alias.Empty()) {
return context;
}
return std::move(context).Renamed(*alias);
}
std::any visitTable_ref(SQLv1::Table_refContext* ctx) override {
TString cluster = GetId(ctx->cluster_expr()).GetOrElse("");
TMaybe<TString> path = GetId(ctx->table_key());
if (path.Empty()) {
return {};
}
return TColumnContext{
.Tables = {
TTableId{std::move(cluster), std::move(*path)},
},
};
}
std::any visitSelect_stmt(SQLv1::Select_stmtContext* ctx) override {
return AccumulatingVisit(ctx->select_kind_parenthesis());
}
std::any visitSelect_core(SQLv1::Select_coreContext* ctx) override {
TColumnContext context = AccumulatingVisit(ctx->result_column());
auto asterisks = std::ranges::partition(context.Columns, [](const TColumnId& x) {
return x.Name != "*";
});
if (std::ranges::empty(asterisks)) {
return context;
}
TColumnContext source = AccumulatingVisit(ctx->join_source());
TColumnContext imported;
for (const TColumnId& qualified : asterisks) {
auto aliased = source.ExtractAliased(qualified.TableAlias);
imported = std::move(imported) | std::move(aliased);
}
context.Columns.erase(asterisks.begin(), asterisks.end());
imported = std::move(imported).Renamed("");
return std::move(context) | std::move(imported);
}
std::any visitResult_column(SQLv1::Result_columnContext* ctx) override {
if (ctx->opt_id_prefix() == nullptr && ctx->TOKEN_ASTERISK() != nullptr) {
return TColumnContext::Asterisk();
}
if (ctx->opt_id_prefix() != nullptr && ctx->TOKEN_ASTERISK() != nullptr) {
TMaybe<TString> alias = GetId(ctx->opt_id_prefix()->an_id());
if (alias.Empty()) {
return TColumnContext::Asterisk();
}
return TColumnContext{
.Columns = {
{.TableAlias = std::move(*alias), .Name = "*"},
},
};
}
TMaybe<TString> column = GetAlias(ctx);
if (column.Defined()) {
return TColumnContext{
.Columns = {
{.Name = std::move(*column)},
},
};
}
return {};
}
private:
TMaybe<TString> GetAlias(SQLv1::Named_single_sourceContext* ctx) const {
TMaybe<TString> alias = GetId(ctx->an_id());
alias = alias.Defined() ? alias : GetId(ctx->an_id_as_compat());
return alias;
}
TMaybe<TString> GetAlias(SQLv1::Result_columnContext* ctx) const {
antlr4::ParserRuleContext* id = nullptr;
if (ctx->TOKEN_AS() == nullptr) {
id = ctx->expr();
} else {
id = ctx->an_id_or_type();
id = id ? id : ctx->an_id_as_compat();
}
return GetId(id);
}
TMaybe<TColumnContext> Head(SQLv1::Select_coreContext* ctx) {
SQLv1::Result_columnContext* column = ctx->result_column(0);
if (column == nullptr) {
return Nothing();
}
std::any any = visit(column);
if (!any.has_value()) {
return Nothing();
}
return std::any_cast<TColumnContext>(any);
}
template <std::derived_from<antlr4::ParserRuleContext> T>
TColumnContext AccumulatingVisit(std::vector<T*> contexts) {
return Accumulate(
contexts,
TColumnContext(),
[this](TColumnContext&& acc, T* ctx) {
std::any any = visit(ctx);
if (!any.has_value()) {
return acc;
}
TColumnContext child = std::move(std::any_cast<TColumnContext>(any));
return std::move(acc) | std::move(child);
});
}
};
class TVisitor: public TSQLv1NarrowingVisitor {
public:
TVisitor(antlr4::TokenStream* tokens, size_t cursorPosition)
: TSQLv1NarrowingVisitor(tokens, cursorPosition)
{
}
std::any visitSql_stmt_core(SQLv1::Sql_stmt_coreContext* ctx) override {
if (IsEnclosing(ctx)) {
return visitChildren(ctx);
}
return {};
}
std::any visitSelect_core(SQLv1::Select_coreContext* ctx) override {
SQLv1::Join_sourceContext* source = ctx->join_source(0);
if (source == nullptr) {
source = ctx->join_source(1);
}
if (source == nullptr) {
return {};
}
return TInferenceVisitor().visit(source);
}
};
} // namespace
TMaybe<TColumnContext> InferColumnContext(
SQLv1::Sql_queryContext* ctx,
antlr4::TokenStream* tokens,
size_t cursorPosition) {
// TODO: add utility `auto ToMaybe<T>(std::any any) -> TMaybe<T>`
std::any result = TVisitor(tokens, cursorPosition).visit(ctx);
if (!result.has_value()) {
return Nothing();
}
return std::any_cast<TColumnContext>(result);
}
} // namespace NSQLComplete
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