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// Copyright (c) 2017-2022 Cloudflare, Inc.
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// Licensed under the Apache 2.0 license found in the LICENSE file or at:
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//     https://opensource.org/licenses/Apache-2.0
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#pragma once
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#include <kj/string.h>
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#include <cstdlib>
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namespace workerd {
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enum class ColorMode {
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  // Always output colors to the console
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  ENABLED,
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  // Output colors to the console if it's a TTY
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  ENABLED_IF_TTY,
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  // Never output colors to the console
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  DISABLED
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};
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// Returns whether we can output color to the console. Even if this returns `true`,
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// we'll only write color codes if the output file is a TTY.
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// TODO(someday): adopt more of Node.js's checks:
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//  https://github.com/nodejs/node/blob/ac2a68c/lib/internal/tty.js#L106
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static ColorMode permitsColor() {
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  const char* forceColorValue = getenv("FORCE_COLOR");
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  if (forceColorValue != nullptr) {
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    auto f = kj::StringPtr(forceColorValue);
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    auto enabled = f == "" || f == "1" || f == "2" || f == "3" || f == "true";
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    return enabled ? ColorMode::ENABLED : ColorMode::DISABLED;
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  } else {
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    auto enabled = getenv("NO_COLOR") == nullptr && getenv("CI") == nullptr;
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    return enabled ? ColorMode::ENABLED_IF_TTY : ColorMode::DISABLED;
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  }
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}
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}  // namespace workerd