use crate::diagnostic::Diagnostic;
use crate::source_range::SourceRange;
use crate::symbol::ParameterSymbol;
use crate::symbol_table::{SymbolInsertError, SymbolTable};
use crate::type_info::TypeInfo;
use std::cell::RefCell;
use std::rc::Rc;

pub struct Parameter {
    declared_name: String,
    declared_name_source_range: SourceRange,
}

impl Parameter {
    pub fn new(declared_name: &str, declared_name_source_range: SourceRange) -> Self {
        Self {
            declared_name: declared_name.into(),
            declared_name_source_range,
        }
    }

    pub fn gather_declared_names(
        &mut self,
        symbol_table: &mut SymbolTable,
    ) -> Result<Rc<RefCell<ParameterSymbol>>, Vec<Diagnostic>> {
        let insert_result = symbol_table.insert_parameter_symbol(ParameterSymbol::new(
            &self.declared_name,
            TypeInfo::Any, // todo
        ));
        match insert_result {
            Ok(parameter_symbol) => Ok(parameter_symbol),
            Err(symbol_insert_error) => match symbol_insert_error {
                SymbolInsertError::AlreadyDeclared(already_declared) => Err(vec![Diagnostic::new(
                    &format!("Parameter {} already declared.", already_declared.name()),
                    self.declared_name_source_range.start(),
                    self.declared_name_source_range.end(),
                )]),
            },
        }
    }
}