src/tint/utils/text/color_mode.cc

// Copyright 2024 The Dawn & Tint Authors
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#include "src/tint/utils/text/color_mode.h"

#include "src/tint/utils/system/env.h"
#include "src/tint/utils/system/terminal.h"
#include "src/tint/utils/text/styled_text_printer.h"
#include "src/tint/utils/text/styled_text_theme.h"

namespace tint {

ColorMode ColorModeDefault() {
    if (!tint::TerminalSupportsColors(stdout)) {
        return ColorMode::kPlain;
    }
    if (auto res = tint::TerminalIsDark(stdout)) {
        return *res ? ColorMode::kDark : ColorMode::kLight;
    }
    if (auto env = tint::GetEnvVar("DARK_BACKGROUND_COLOR"); !env.empty()) {
        return env != "0" ? ColorMode::kDark : ColorMode::kLight;
    }
    if (auto env = tint::GetEnvVar("LIGHT_BACKGROUND_COLOR"); !env.empty()) {
        return env != "0" ? ColorMode::kLight : ColorMode::kDark;
    }
    return ColorMode::kDark;
}

std::unique_ptr<tint::StyledTextPrinter> CreatePrinter(ColorMode mode) {
    switch (mode) {
        case ColorMode::kLight:
            return tint::StyledTextPrinter::Create(stderr, tint::StyledTextTheme::kDefaultLight);
        case ColorMode::kDark:
            return tint::StyledTextPrinter::Create(stderr, tint::StyledTextTheme::kDefaultDark);
        case ColorMode::kPlain:
            break;
    }
    return tint::StyledTextPrinter::CreatePlain(stderr);
}

}  // namespace tint