rqml/src/parser.rs

extern crate pest;

use crate::Value::{QmlIdent, QmlNumber, QmlString};
use pest::iterators::Pairs;
use pest::Parser;
use std::collections::HashMap;
use std::fs::read_to_string;

#[derive(Parser)]
#[grammar = "../pest/qml.pest"]
struct QmlParser;

#[derive(Debug, Clone)]
pub enum Value {
    QmlString(String),
    QmlNumber(f64),
    QmlIdent(String),
}

#[derive(Debug, Clone)]
pub struct QML {
    pub properties: HashMap<String, Value>,
    pub children: Vec<(String, QML)>,
}

pub fn parse_qml(path: &str) -> QML {
    let qml_file = read_to_string(path).unwrap();
    let qml_tokens =
        QmlParser::parse(Rule::qml, qml_file.as_str()).unwrap_or_else(|e| panic!("{}", e));
    parse(qml_tokens)
}

fn parse(qml: Pairs<Rule>) -> QML {
    let mut qmldoc = QML {
        properties: Default::default(),
        children: vec![],
    };
    for pair in qml {
        //   println!("Rule {:?} Str {}", pair.as_rule(), pair.as_str());

        match pair.as_rule() {
            Rule::import => {
                let mut tokens = pair.into_inner();
                println!("Found new Import {} ", tokens.next().unwrap().as_str());
            }
            Rule::body => {
                let mut tokens = pair.into_inner();
                let ident = tokens.next().unwrap().as_str();
                println!("Found new Body: {} ", ident);
                qmldoc
                    .children
                    .push((String::from(ident), parse(tokens.into_iter())));
            }
            Rule::property => {
                let mut tokens = pair.into_inner();
                let ident = tokens.next().unwrap().as_str();
                let value = tokens.next().unwrap();
                // let value = tokens.next().unwrap().as_str();
                match value.as_rule() {
                    Rule::number => {
                        let num: f64 = value.as_str().parse().unwrap();
                        println!("Found new Property: {} {:?}", ident, num);
                        qmldoc
                            .properties
                            .insert(String::from(ident), QmlNumber(num));
                    }
                    Rule::string => {
                        println!("Found new Property: {} {}", ident, value.as_str());
                        qmldoc.properties.insert(
                            String::from(ident),
                            QmlString(String::from(value.into_inner().next().unwrap().as_str())),
                        );
                    }
                    Rule::ident => {
                        println!("Found new Property: {} {}", ident, value.as_str());
                        qmldoc
                            .properties
                            .insert(String::from(ident), QmlIdent(String::from(value.as_str())));
                    }
                    _ => {}
                }
            }
            Rule::function => {
                let mut tokens = pair.into_inner();
                let ident = tokens.next().unwrap().as_str();
                let value = tokens.concat();
                qmldoc.properties.insert(
                    String::from(ident),
                    QmlString(String::from(value.clone().trim())),
                );
            }
            _ => return parse(pair.into_inner()),
        }
    }
    qmldoc
}