#[macro_use]
extern crate log;

extern crate toml;

pub mod modelica_parser;
pub mod modelica_ast;

use std::path::Path;
use std::fs;
use std::io::Read;
use std::fs::File;

#[derive(Debug, PartialEq)]
pub struct ModelMetadata {
    pub name_en: String,
    pub description_en: Option<String>,
    pub vars: Vec<ModelVar>,
}

#[derive(Debug, PartialEq)]
pub enum ModelVarType {
    Independent,
    Dependent,
    Constant,
    // XXX:
    Time,
    State,
    Parameter,
}

#[derive(Debug, PartialEq)]
pub struct ModelVar {
    pub slug: String,
    pub name_en: Option<String>,
    pub vtype: ModelVarType,
    pub latex: Option<String>,
    pub units_si: Option<String>,
}

#[derive(Debug, PartialEq)]
pub struct ModelEntry {
    pub ast: modelica_ast::ModelicaModel,
    pub metadata: ModelMetadata,
    pub markdown: String,
}

// TODO: this
pub fn parse_metadata(raw: String) -> Result<ModelMetadata,String> {
    let root = toml::Parser::new(&raw).parse().unwrap();
    let model = root.get("model").unwrap().as_table().unwrap();
    let variables = root.get("variables").unwrap().as_table().unwrap();
    let mut vars = vec![];
    for (slug, info) in variables {
        let info = info.as_table().unwrap();
        let vtype = match info.get("type").unwrap().as_str().unwrap() {
            "independent" => ModelVarType::Independent,
            "dependent" => ModelVarType::Dependent,
            "constant" => ModelVarType::Constant,
            "time" => ModelVarType::Time,
            "state" => ModelVarType::State,
            "parameter" => ModelVarType::Parameter,
            other => return Err(format!("Unknown variable type: {}", other)),
        };
        vars.push(ModelVar {
            slug: slug.to_string(),
            name_en: info.get("name-en").map(|x| x.as_str().unwrap().to_string()),
            vtype: vtype,
            latex: info.get("latex").map(|x| x.as_str().unwrap().to_string()),
            units_si: info.get("units-si").map(|x| x.as_str().unwrap().to_string()),
        });
    }
    Ok(ModelMetadata {
        name_en: model.get("name-en").unwrap().as_str().unwrap().to_string(),
        description_en: model.get("description-en").map(|x| x.as_str().unwrap().to_string()),
        vars: vars,
    })
}

pub fn load_model_entry(p: &Path) -> Result<ModelEntry,String> {
    debug!("Attempting to load model from: {:?}", p);

    let ast = {
        let mut s = String::new();
        try!(File::open(p.join("model.modelica")).and_then(|mut f| f.read_to_string(&mut s)).map_err(|e| e.to_string()));
        try!(modelica_parser::parse_model(&s).map_err(|e| format!("{:?}", e)))
    };

    let metadata = {
        let mut s = String::new();
        try!(File::open(p.join("metadata.toml")).and_then(|mut f| f.read_to_string(&mut s)).map_err(|e| e.to_string()));
        parse_metadata(s).unwrap()
    };

    let markdown = {
        let mut s = String::new();
        try!(File::open(p.join("page.md")).and_then(|mut f| f.read_to_string(&mut s)).map_err(|e| e.to_string()));
        s
    };

    Ok(ModelEntry {
        ast: ast,
        metadata: metadata,
        markdown: markdown,
    })
}

// TODO: have this check for model.modelica etc
pub fn search_models(p: &Path) -> Vec<String> {
    if fs::metadata(p).unwrap().is_dir() {
        fs::read_dir(p).unwrap()
                       .map(|x| x.unwrap())
                       .filter(|x| x.metadata().unwrap().is_dir())
                       .map(|x| x.path().to_string_lossy().to_string())
                       .collect()
    } else {
        vec![]
    }
}

/* ******************************** Tests ******************************* */

#[test]
fn test_parse_metadata() {
    assert_eq!(parse_metadata("asdf".to_string()).unwrap(),
        ModelMetadata {
            name_en: "Bogus Dummy Model".to_string(),
            description_en: None,
            vars: vec![],
        });
}

#[test]
fn test_load_model_entry() {
    load_model_entry(Path::new("./examples/classic_gravitation/")).unwrap();
}

#[test]
fn test_search_models() {
    assert_eq!(search_models(Path::new("./examples/")).len() > 1, true);
}

#[test]
fn test_lexical() {
    assert_eq!(&format!("{:?}", modelica_parser::parse_integer("+123").unwrap()),
               "123");
    assert_eq!(&format!("{:?}", modelica_parser::parse_integer("-9").unwrap()),
               "-9");
    assert_eq!(&format!("{:?}", modelica_parser::parse_float("-1.0e0").unwrap()),
               "-1");
    assert_eq!(&format!("{:?}", modelica_parser::parse_float("123.456").unwrap()),
               "123.456");
}

#[test]
fn test_parse() {
    let example1 =
r#"model MinimalModel
  Real x;
equation
  x = 1;
end MinimalModel;
"#;
    assert_eq!(&format!("{:?}", modelica_parser::parse_model(example1).unwrap()), example1);

    let example2 =
r#"model MinimalModel
  parameter Real a;
  Real b;
equation
  connect(a, b);
  a = 1;
  b = ((abs(a) + 2) / 4);
end MinimalModel;
"#;
    assert_eq!(&format!("{:?}", modelica_parser::parse_model(example2).unwrap()), example2);
}