#![cfg(test)]

use crate::symbol_table::SymbolTable;
use crate::tree_walk_eval::State;

fn evaluate_input(input: &str) -> Result<String, String> {
  let ast = crate::util::quick_ast(input);
  let mut symbol_table = SymbolTable::new();
  symbol_table.process_ast(&ast).unwrap();
  let reduced_ir = crate::reduced_ir::reduce(&ast, &symbol_table);
  reduced_ir.debug(&symbol_table);
  let mut state = State::new();
  let mut outputs = state.evaluate(reduced_ir, true);
  outputs.pop().unwrap()
}

fn eval_assert(input: &str, expected: &str) {
    assert_eq!(evaluate_input(input), Ok(expected.to_string()));
}

#[test]
fn test_basic_eval() {
  eval_assert("1 + 2", "3");
  eval_assert("let mut a = 1; a = 2", "()");
  eval_assert("let mut a = 1; a = a + 2; a", "3");
}

#[test]
fn op_eval() {
  eval_assert("- 13", "-13");
  eval_assert("10 - 2", "8");
}

#[test]
fn function_eval() {
  eval_assert("fn oi(x) { x + 1 }; oi(4)", "5");
  eval_assert("fn oi(x) { x + 1 }; oi(1+2)", "4");
}

#[test]
fn scopes() {
  let scope_ok = r#"
    let a = 20
    fn haha() {
      let something = 38
      let a = 10
      a
    }
    haha()
    "#;

    eval_assert(scope_ok, "10");

    let scope_ok = r#"
    let a = 20
    fn queque() {
      let a = 10
      a
    }
    a
    "#;
    eval_assert(scope_ok, "20");
}

#[test]
fn if_is_patterns() {
  let source = r#"
type Option<T> = Some(T) | None
let x = Option::Some(9); if x is Option::Some(q) then { q } else { 0 }"#;

  eval_assert(source, "9");

  let source = r#"
type Option<T> = Some(T) | None
let x = Option::None; if x is Option::Some(q) then { q } else { 0 }"#;
  eval_assert(source, "0");
}



#[test]
fn basic_lambda_evaluation_1() {
    let source = r#"
let q = \(x, y) { x * y }
let x = q(5, 2)
let y = \(m, n, o) { m + n + o }(1,2,3)
(x, y)
"#;

eval_assert(source, r"(10, 6)");
}

#[test]
fn basic_lambda_evaluation_2() {
  let source = r#"
fn milta() {
  \(x) { x + 33 }
}
milta()(10)
  "#;

  eval_assert(source, "43");
  }

#[test]
fn import_all() {
  let source = r#"
type Option<T> = Some(T) | None
import Option::*
let x = Some(9); if x is Some(q) then { q } else { 0 }"#;
  //eval_assert(source, "9");
}