#include "documentation.h"

#include <yql/essentials/sql/v1/ide/completion/name/service/name_service.h>

namespace NSQLComplete {

namespace {

class TStaticDocumentation: public IDocumentation {
public:
    explicit TStaticDocumentation(TDocByNormalizedNameMap docs)
        : Docs_(std::move(docs))
    {
    }

    TMaybe<TString> Lookup(TStringBuf name) const override {
        if (auto* ptr = Docs_.FindPtr(Normalized(name))) {
            return *ptr;
        }
        return Nothing();
    }

private:
    TString Normalized(TStringBuf name) const {
        return NormalizeName(name);
    }

    TDocByNormalizedNameMap Docs_;
};

class TReservedDocumentation: public IDocumentation {
public:
    TReservedDocumentation(
        IDocumentation::TPtr primary, IDocumentation::TPtr fallback)
        : Primary_(std::move(primary))
        , Fallback_(std::move(fallback))
    {
    }

    TMaybe<TString> Lookup(TStringBuf name) const override {
        return Primary_->Lookup(name).Or([name, f = Fallback_] {
            return f->Lookup(name);
        });
    }

private:
    IDocumentation::TPtr Primary_;
    IDocumentation::TPtr Fallback_;
};

} // namespace

IDocumentation::TPtr MakeStaticDocumentation(TDocByNormalizedNameMap docs) {
    return new TStaticDocumentation(std::move(docs));
}

IDocumentation::TPtr MakeReservedDocumentation(
    IDocumentation::TPtr primary, IDocumentation::TPtr fallback) {
    return new TReservedDocumentation(std::move(primary), std::move(fallback));
}

} // namespace NSQLComplete