use dust_lang::*;

#[test]
fn allow_access_to_parent_scope() {
    let source = r#"
        let x = 1;
        {
            x
        }
    "#;

    assert_eq!(run(source), Ok(Some(ConcreteValue::Integer(1))));
}

#[test]
fn block_scope() {
    let source = "
        let a = 0;
        {
            let b = 42;
            {
                let c = 1;
            }
            let d = 2;
        }
        let e = 1;
    ";

    assert_eq!(
        compile(source),
        Ok(Chunk::with_data(
            None,
            FunctionType {
                type_parameters: None,
                value_parameters: None,
                return_type: Box::new(Type::None),
            },
            vec![
                (
                    Instruction::load_constant(Destination::Register(0), 0, false),
                    Span(17, 18)
                ),
                (Instruction::define_local(0, 0, false), Span(13, 14)),
                (
                    Instruction::load_constant(Destination::Register(1), 2, false),
                    Span(50, 52)
                ),
                (Instruction::define_local(1, 1, false), Span(46, 47)),
                (
                    Instruction::load_constant(Destination::Register(2), 4, false),
                    Span(92, 93)
                ),
                (Instruction::define_local(2, 2, false), Span(88, 89)),
                (
                    Instruction::load_constant(Destination::Register(3), 6, false),
                    Span(129, 130)
                ),
                (Instruction::define_local(3, 3, false), Span(125, 126)),
                (
                    Instruction::load_constant(Destination::Register(4), 4, false),
                    Span(158, 159)
                ),
                (Instruction::define_local(4, 4, false), Span(154, 155)),
                (Instruction::r#return(false), Span(165, 165))
            ],
            vec![
                ConcreteValue::Integer(0),
                ConcreteValue::string("a"),
                ConcreteValue::Integer(42),
                ConcreteValue::string("b"),
                ConcreteValue::Integer(1),
                ConcreteValue::string("c"),
                ConcreteValue::Integer(2),
                ConcreteValue::string("d"),
                ConcreteValue::string("e"),
            ],
            vec![
                Local::new(1, Type::Integer, false, Scope::new(0, 0)),
                Local::new(3, Type::Integer, false, Scope::new(1, 1)),
                Local::new(5, Type::Integer, false, Scope::new(2, 2)),
                Local::new(7, Type::Integer, false, Scope::new(1, 1)),
                Local::new(8, Type::Integer, false, Scope::new(0, 0)),
            ]
        )),
    );

    assert_eq!(run(source), Ok(None));
}

#[test]
fn multiple_block_scopes() {
    let source = "
        let a = 0;
        {
            let b = 42;
            {
                let c = 1;
            }
            let d = b;
        }
        let q = a;
        {
            let b = 42;
            {
                let c = 1;
            }
            let d = b;
        }
        let e = a;
    ";

    assert_eq!(
        compile(source),
        Ok(Chunk::with_data(
            None,
            FunctionType {
                type_parameters: None,
                value_parameters: None,
                return_type: Box::new(Type::None),
            },
            vec![
                (
                    Instruction::load_constant(Destination::Register(0), 0, false),
                    Span(17, 18)
                ),
                (Instruction::define_local(0, 0, false), Span(13, 14)),
                (
                    Instruction::load_constant(Destination::Register(1), 2, false),
                    Span(50, 52)
                ),
                (Instruction::define_local(1, 1, false), Span(46, 47)),
                (
                    Instruction::load_constant(Destination::Register(2), 4, false),
                    Span(92, 93)
                ),
                (Instruction::define_local(2, 2, false), Span(88, 89)),
                (
                    Instruction::get_local(Destination::Register(3), 1),
                    Span(129, 130)
                ),
                (Instruction::define_local(3, 3, false), Span(125, 126)),
                (
                    Instruction::get_local(Destination::Register(4), 0),
                    Span(158, 159)
                ),
                (Instruction::define_local(4, 4, false), Span(154, 155)),
                (
                    Instruction::load_constant(Destination::Register(5), 2, false),
                    Span(191, 193)
                ),
                (Instruction::define_local(5, 5, false), Span(187, 188)),
                (
                    Instruction::load_constant(Destination::Register(6), 4, false),
                    Span(233, 234)
                ),
                (Instruction::define_local(6, 6, false), Span(229, 230)),
                (
                    Instruction::get_local(Destination::Register(7), 5),
                    Span(270, 271)
                ),
                (Instruction::define_local(7, 7, false), Span(266, 267)),
                (
                    Instruction::get_local(Destination::Register(8), 0),
                    Span(299, 300)
                ),
                (Instruction::define_local(8, 8, false), Span(295, 296)),
                (Instruction::r#return(false), Span(306, 306))
            ],
            vec![
                ConcreteValue::Integer(0),
                ConcreteValue::string("a"),
                ConcreteValue::Integer(42),
                ConcreteValue::string("b"),
                ConcreteValue::Integer(1),
                ConcreteValue::string("c"),
                ConcreteValue::string("d"),
                ConcreteValue::string("q"),
                ConcreteValue::string("e"),
            ],
            vec![
                Local::new(1, Type::Integer, false, Scope::new(0, 0)),
                Local::new(3, Type::Integer, false, Scope::new(1, 1)),
                Local::new(5, Type::Integer, false, Scope::new(2, 2)),
                Local::new(6, Type::Integer, false, Scope::new(1, 1)),
                Local::new(7, Type::Integer, false, Scope::new(0, 0)),
                Local::new(3, Type::Integer, false, Scope::new(1, 3)),
                Local::new(5, Type::Integer, false, Scope::new(2, 4)),
                Local::new(6, Type::Integer, false, Scope::new(1, 3)),
                Local::new(8, Type::Integer, false, Scope::new(0, 0)),
            ]
        )),
    );

    assert_eq!(run(source), Ok(None));
}

#[test]
fn disallow_access_to_child_scope() {
    let source = r#"
        {
            let x = 1;
        }
        x
    "#;

    assert_eq!(
        run(source),
        Err(CreateReport::Compile {
            error: CompileError::VariableOutOfScope {
                identifier: "x".to_string(),
                position: Span(52, 53),
                variable_scope: Scope::new(1, 1),
                access_scope: Scope::new(0, 0),
            },
            source
        })
    );
}

#[test]
fn disallow_access_to_child_scope_nested() {
    let source = r#"
        {
            {
                let x = 1;
            }
            x
        }
    "#;

    assert_eq!(
        run(source),
        Err(CreateReport::Compile {
            error: CompileError::VariableOutOfScope {
                identifier: "x".to_string(),
                position: Span(78, 79),
                variable_scope: Scope::new(2, 2),
                access_scope: Scope::new(1, 1),
            },
            source
        })
    );
}

#[test]
fn disallow_access_to_sibling_scope() {
    let source = r#"
        {
            let x = 1;
        }
        {
            x
        }
    "#;

    assert_eq!(
        run(source),
        Err(CreateReport::Compile {
            error: CompileError::VariableOutOfScope {
                identifier: "x".to_string(),
                variable_scope: Scope::new(1, 1),
                access_scope: Scope::new(1, 2),
                position: Span(66, 67),
            },
            source
        })
    );
}

#[test]
fn disallow_access_to_sibling_scope_nested() {
    let source = r#"
        {
            {
                let x = 1;
            }
            {
                x
            }
        }
    "#;

    assert_eq!(
        run(source),
        Err(CreateReport::Compile {
            error: CompileError::VariableOutOfScope {
                identifier: "x".to_string(),
                variable_scope: Scope::new(2, 2),
                access_scope: Scope::new(2, 3),
                position: Span(96, 97),
            },
            source
        })
    );
}