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use crate::sbml::import::MATHML;
use roxmltree::{ExpandedName, Node};
use std::option::Option::Some;
const APPLY_TAG: (&str, &str) = (MATHML, "apply");
const NUMBER_TAG: (&str, &str) = (MATHML, "cn");
const IDENTIFIER_TAG: (&str, &str) = (MATHML, "ci");
const SYMBOL_TAG: (&str, &str) = (MATHML, "csymbol");
const TRUE_TAG: (&str, &str) = (MATHML, "true");
const FALSE_TAG: (&str, &str) = (MATHML, "false");
#[derive(Clone, Debug, PartialEq, Eq)]
pub enum MathMl {
Boolean(bool),
Integer(i64),
Identifier(String),
Apply(String, Vec<MathMl>),
SymbolApply(String, Vec<MathMl>),
}
pub fn read_mathml(math: Node) -> Result<MathMl, String> {
let child_count = math.children().filter(|c| c.is_element()).count();
if child_count == 0 {
return Err("Tag <math> has no children.".to_string());
}
if child_count > 1 {
return Err("More than one child in a <math> tag.".to_string());
}
read_expression(math.first_element_child().unwrap())
}
fn read_expression(math: Node) -> Result<MathMl, String> {
if math.tag_name() == ExpandedName::from(TRUE_TAG) {
return Ok(MathMl::Boolean(true));
}
if math.tag_name() == ExpandedName::from(FALSE_TAG) {
return Ok(MathMl::Boolean(false));
}
if math.tag_name() == ExpandedName::from(IDENTIFIER_TAG) {
let id = math
.text()
.map(|s| s.trim().to_string())
.unwrap_or_default();
if id.is_empty() {
return Err("Empty math identifier.".to_string());
}
return Ok(MathMl::Identifier(id));
}
if math.tag_name() == ExpandedName::from(NUMBER_TAG) {
let value = math
.text()
.map(|s| s.trim().to_string())
.unwrap_or_default();
let num_type = math.attribute((MATHML, "type"));
if num_type.is_some() && num_type.unwrap() != "integer" {
return Err(format!(
"Non-integer numeric types ({}) are not supported.",
num_type.unwrap()
));
}
return if let Ok(parsed) = value.parse::<i64>() {
Ok(MathMl::Integer(parsed))
} else {
Err(format!("Invalid integer constant: `{}`.", value))
};
}
if math.tag_name() == ExpandedName::from(APPLY_TAG) {
let op_tag = math.first_element_child();
return if let Some(op_tag) = op_tag {
let mut args = Vec::new();
let mut arg = op_tag.next_sibling_element();
while let Some(inner) = arg {
args.push(read_expression(inner)?);
arg = inner.next_sibling_element();
}
if op_tag.tag_name() == ExpandedName::from(SYMBOL_TAG) {
let symbol = op_tag
.text()
.map(|s| s.trim().to_string())
.unwrap_or_default();
if symbol.is_empty() {
Err("Empty <csymbol> in MathML.".to_string())
} else {
Ok(MathMl::SymbolApply(symbol, args))
}
} else {
Ok(MathMl::Apply(op_tag.tag_name().name().to_string(), args))
}
} else {
Err("MathML <apply> with no child elements.".to_string())
};
}
Err(format!(
"Unexpected MathML tag `{}`.",
math.tag_name().name()
))
}
impl MathMl {
pub fn contains_identifier(&self, id: &str) -> bool {
match self {
MathMl::Boolean(_) => false,
MathMl::Integer(_) => false,
MathMl::Identifier(value) => value == id,
MathMl::SymbolApply(_, args) => args.iter().any(|a| a.contains_identifier(id)),
MathMl::Apply(_, args) => args.iter().any(|a| a.contains_identifier(id)),
}
}
}