omena-cascade 0.3.0

Cascade-formal substrate for Omena CSS
Documentation 
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//! CSS property metadata lookups (inheritance, initial values) over the generated authority.

use crate::property_metadata_idl_generated::{
    CSS_PROPERTY_METADATA_RECORDS_V1, CssPropertyMetadataRecordStaticV1,
};

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum CssPropertyInitialValueV0 {
    Literal(&'static str),
    GuaranteedInvalid,
    Unknown,
}

#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub enum CssPropertyInheritanceV0 {
    Inherited,
    NotInherited,
    Unknown,
}

pub fn css_property_metadata_for_property(
    property: &str,
) -> Option<&'static CssPropertyMetadataRecordStaticV1> {
    css_property_metadata_for_property_in_records(property, CSS_PROPERTY_METADATA_RECORDS_V1)
}

#[doc(hidden)]
pub fn css_property_metadata_for_property_in_records(
    property: &str,
    records: &'static [CssPropertyMetadataRecordStaticV1],
) -> Option<&'static CssPropertyMetadataRecordStaticV1> {
    records
        .binary_search_by_key(&property, |record| record.canonical_name)
        .ok()
        .map(|index| &records[index])
}

pub fn css_property_is_inherited(property: &str) -> CssPropertyInheritanceV0 {
    if property.starts_with("--") {
        return CssPropertyInheritanceV0::Inherited;
    }

    match css_property_metadata_for_property(property).and_then(|record| record.inherited) {
        Some(true) => CssPropertyInheritanceV0::Inherited,
        Some(false) => CssPropertyInheritanceV0::NotInherited,
        None => CssPropertyInheritanceV0::Unknown,
    }
}

pub fn css_property_initial_value(property: &str) -> CssPropertyInitialValueV0 {
    if property.starts_with("--") {
        return CssPropertyInitialValueV0::GuaranteedInvalid;
    }

    css_property_metadata_for_property(property)
        .and_then(|record| record.initial_value)
        .map(CssPropertyInitialValueV0::Literal)
        .unwrap_or(CssPropertyInitialValueV0::Unknown)
}