/*

 * Copyright (c) 2023, MacDue <macdue@dueutil.tech>

 *

 * SPDX-License-Identifier: BSD-2-Clause

 */

#include <LibGfx/AntiAliasingPainter.h>

#include <LibGfx/Painter.h>

#include <LibGfx/PathClipper.h>

namespace Gfx {

// FIXME: This pretty naive, we should be able to cut down the allocations here

// (especially for the paint style which is a bit sad).

ErrorOr<PathClipper> PathClipper::create(Painter& painter, ClipPath const& clip_path)

{

    auto bounding_box = enclosing_int_rect(clip_path.path.bounding_box());

    IntRect actual_save_rect {};

    auto maybe_bitmap = painter.get_region_bitmap(bounding_box, BitmapFormat::BGRA8888, actual_save_rect);

    RefPtr<Bitmap> saved_clip_region;

    if (!maybe_bitmap.is_error()) {

        saved_clip_region = maybe_bitmap.release_value();

    } else if (actual_save_rect.is_empty()) {

        // This is okay, no need to report an error.

    } else {

        return maybe_bitmap.release_error();

    }

    painter.save();

    painter.add_clip_rect(bounding_box);

    return PathClipper(move(saved_clip_region), bounding_box, clip_path);

}

ErrorOr<void> PathClipper::apply_clip(Painter& painter)

{

    painter.restore();

    if (!m_saved_clip_region)

        return {};

    IntRect actual_save_rect {};

    auto clip_area = TRY(painter.get_region_bitmap(m_bounding_box, BitmapFormat::BGRA8888, actual_save_rect));

    painter.blit(actual_save_rect.location(), *m_saved_clip_region, m_saved_clip_region->rect(), 1.0f, false);

    AntiAliasingPainter aa_painter { painter };

    auto fill_offset = m_bounding_box.location() - actual_save_rect.location();

    aa_painter.fill_path(m_clip_path.path, TRY(BitmapPaintStyle::create(clip_area, fill_offset)), 1.0f, m_clip_path.winding_rule);

    return {};

}

}