use super::*;

impl TopLevelComposer {
    pub fn make_primitives() -> (PrimitiveStore, Unifier) {
        let mut unifier = Unifier::new();
        let int32 = unifier.add_ty(TypeEnum::TObj {
            obj_id: DefinitionId(0),
            fields: HashMap::new().into(),
            params: HashMap::new().into(),
        });
        let int64 = unifier.add_ty(TypeEnum::TObj {
            obj_id: DefinitionId(1),
            fields: HashMap::new().into(),
            params: HashMap::new().into(),
        });
        let float = unifier.add_ty(TypeEnum::TObj {
            obj_id: DefinitionId(2),
            fields: HashMap::new().into(),
            params: HashMap::new().into(),
        });
        let bool = unifier.add_ty(TypeEnum::TObj {
            obj_id: DefinitionId(3),
            fields: HashMap::new().into(),
            params: HashMap::new().into(),
        });
        let none = unifier.add_ty(TypeEnum::TObj {
            obj_id: DefinitionId(4),
            fields: HashMap::new().into(),
            params: HashMap::new().into(),
        });
        let primitives = PrimitiveStore { int32, int64, float, bool, none };
        crate::typecheck::magic_methods::set_primitives_magic_methods(&primitives, &mut unifier);
        (primitives, unifier)
    }

    /// already include the definition_id of itself inside the ancestors vector
    /// when first regitering, the type_vars, fields, methods, ancestors are invalid
    pub fn make_top_level_class_def(
        index: usize,
        resolver: Option<Arc<Box<dyn SymbolResolver + Send + Sync>>>,
        name: &str,
    ) -> TopLevelDef {
        TopLevelDef::Class {
            name: name.to_string(),
            object_id: DefinitionId(index),
            type_vars: Default::default(),
            fields: Default::default(),
            methods: Default::default(),
            ancestors: Default::default(),
            resolver,
        }
    }

    /// when first registering, the type is a invalid value
    pub fn make_top_level_function_def(
        name: String,
        ty: Type,
        resolver: Option<Arc<Box<dyn SymbolResolver + Send + Sync>>>,
    ) -> TopLevelDef {
        TopLevelDef::Function {
            name,
            signature: ty,
            var_id: Default::default(),
            instance_to_symbol: Default::default(),
            instance_to_stmt: Default::default(),
            resolver,
        }
    }

    pub fn make_class_method_name(mut class_name: String, method_name: &str) -> String {
        class_name.push_str(method_name);
        class_name
    }

    pub fn get_class_method_def_info(
        class_methods_def: &[(String, Type, DefinitionId)],
        method_name: &str,
    ) -> Result<(Type, DefinitionId), String> {
        for (name, ty, def_id) in class_methods_def {
            if name == method_name {
                return Ok((*ty, *def_id));
            }
        }
        Err(format!("no method {} in the current class", method_name))
    }

    /// get all base class def id of a class, excluding itself. \
    /// this function should called only after the direct parent is set
    /// and before all the ancestors are set
    /// and when we allow single inheritance \
    /// the order of the returned list is from the child to the deepest ancestor
    pub fn get_all_ancestors_helper(
        child: &TypeAnnotation,
        temp_def_list: &[Arc<RwLock<TopLevelDef>>],
    ) -> Vec<TypeAnnotation> {
        let mut result: Vec<TypeAnnotation> = Vec::new();
        let mut parent = Self::get_parent(child, temp_def_list);
        while let Some(p) = parent {
            parent = Self::get_parent(&p, temp_def_list);
            result.push(p);
        }
        result
    }

    fn get_parent(
        child: &TypeAnnotation,
        temp_def_list: &[Arc<RwLock<TopLevelDef>>],
    ) -> Option<TypeAnnotation> {
        let child_id =
            if let TypeAnnotation::CustomClassKind { id, .. } = child { *id } else { return None };
        let child_def = temp_def_list.get(child_id.0).unwrap();
        let child_def = child_def.read();
        if let TopLevelDef::Class { ancestors, .. } = &*child_def {
            Some(ancestors[0].clone())
        } else {
            None
        }
    }
}