// Copyright 2018-2020 the Deno authors. All rights reserved. MIT license.
use serde::Serialize;
use swc_ecma_ast;

use super::parser::DocParser;
use super::ts_type::ts_type_ann_to_def;
use super::ts_type::TsTypeDef;

#[derive(Debug, Serialize, Clone)]
#[serde(rename_all = "camelCase")]
pub struct VariableDef {
  pub ts_type: Option<TsTypeDef>,
  pub kind: swc_ecma_ast::VarDeclKind,
}

pub fn get_doc_for_var_decl(
  doc_parser: &DocParser,
  var_decl: &swc_ecma_ast::VarDecl,
) -> (String, VariableDef) {
  assert!(!var_decl.decls.is_empty());
  // TODO: support multiple declarators
  let var_declarator = var_decl.decls.get(0).unwrap();

  let var_name = match &var_declarator.name {
    swc_ecma_ast::Pat::Ident(ident) => ident.sym.to_string(),
    _ => "<TODO>".to_string(),
  };

  let maybe_ts_type = match &var_declarator.name {
    swc_ecma_ast::Pat::Ident(ident) => ident
      .type_ann
      .as_ref()
      .map(|rt| ts_type_ann_to_def(&doc_parser.source_map, rt)),
    _ => None,
  };

  let variable_def = VariableDef {
    ts_type: maybe_ts_type,
    kind: var_decl.kind,
  };

  (var_name, variable_def)
}