//===- FormatCommon.h - Formatters for common LLVM types --------*- C++ -*-===//

//

// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.

// See https://llvm.org/LICENSE.txt for license information.

// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception

//

//===----------------------------------------------------------------------===//

#ifndef LLVM_SUPPORT_FORMATCOMMON_H

#define LLVM_SUPPORT_FORMATCOMMON_H

#include "llvm/ADT/SmallString.h"

#include "llvm/Support/FormatVariadicDetails.h"

#include "llvm/Support/raw_ostream.h"

namespace llvm {

enum class AlignStyle { Left, Center, Right };

struct FmtAlign {

  detail::format_adapter &Adapter;

  AlignStyle Where;

  size_t Amount;

  char Fill;

  FmtAlign(detail::format_adapter &Adapter, AlignStyle Where, size_t Amount,

           char Fill = ' ')

      : Adapter(Adapter), Where(Where), Amount(Amount), Fill(Fill) {}

  void format(raw_ostream &S, StringRef Options) {

    // If we don't need to align, we can format straight into the underlying

    // stream.  Otherwise we have to go through an intermediate stream first

    // in order to calculate how long the output is so we can align it.

    // TODO: Make the format method return the number of bytes written, that

    // way we can also skip the intermediate stream for left-aligned output.

    if (Amount == 0) {

      Adapter.format(S, Options);

      return;

    }

    SmallString<64> Item;

    raw_svector_ostream Stream(Item);

    Adapter.format(Stream, Options);

    if (Amount <= Item.size()) {

      S << Item;

      return;

    }

    size_t PadAmount = Amount - Item.size();

    switch (Where) {

    case AlignStyle::Left:

      S << Item;

      fill(S, PadAmount);

      break;

    case AlignStyle::Center: {

      size_t X = PadAmount / 2;

      fill(S, X);

      S << Item;

      fill(S, PadAmount - X);

      break;

    }

    default:

      fill(S, PadAmount);

      S << Item;

      break;

    }

  }

private:

  void fill(llvm::raw_ostream &S, uint32_t Count) {

    for (uint32_t I = 0; I < Count; ++I)

      S << Fill;

  }

};

}

#endif