// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this
// file, You can obtain one at http://mozilla.org/MPL/2.0/.

use svgdom::{
    Color,
};

use super::prelude::*;


/// Resolves default `clipPath` attributes.
pub fn resolve_clip_path_attributes(doc: &Document) {
    for mut node in doc.root().descendants().filter(|n| n.is_tag_name(EId::ClipPath)) {
        let units = node.attributes().get_str_or(AId::ClipPathUnits, "userSpaceOnUse").to_string();
        node.set_attribute((AId::ClipPathUnits, units));
    }
}

/// Converts the `clipPath` content to a black and white one.
///
/// The `clipPath` is implemented using a 1bit-like mask.
/// So to create it we have to draw all the `clipPath` children
/// with a black fill and without a stroke.
pub fn prepare_clip_path_children(doc: &Document) {
    for node in doc.root().descendants().filter(|n| n.is_tag_name(EId::ClipPath)) {
        for (_, mut child) in node.descendants().svg() {
            // Set fill to black.
            child.set_attribute((AId::Fill, Color::black()));

            // Remove stroke.
            child.set_attribute((AId::Stroke, AValue::None));

            // Disable opacity.
            child.set_attribute((AId::Opacity, 1.0));

            // We don't have a separate 'fill-rule' for clipPath, so use an existing property.
            //
            // Note that Tree::to_svgdom will convert it to 'clip-rule'.
            let clip_rule = child.attributes().get_str_or(AId::ClipRule, "nonzero").to_string();
            child.set_attribute((AId::FillRule, clip_rule));
        }
    }
}