mago-analyzer 1.45.0

use std::borrow::Cow;
use std::sync::Arc;

use mago_allocator::Arena;
use mago_codex::identifier::function_like::FunctionLikeIdentifier;
use mago_codex::misc::GenericParent;
use mago_codex::ttype::TType;
use mago_codex::ttype::TypeRef;
use mago_codex::ttype::add_union_type;
use mago_codex::ttype::atomic::TAtomic;
use mago_codex::ttype::atomic::array::TArray;
use mago_codex::ttype::atomic::callable::TCallable;
use mago_codex::ttype::atomic::conditional::TConditional;
use mago_codex::ttype::atomic::derived::TDerived;
use mago_codex::ttype::atomic::mixed::TMixed;
use mago_codex::ttype::atomic::object::TObject;
use mago_codex::ttype::atomic::reference::TReference;
use mago_codex::ttype::atomic::scalar::TScalar;
use mago_codex::ttype::atomic::scalar::class_like_string::TClassLikeString;
use mago_codex::ttype::combiner::CombinerOptions;
use mago_codex::ttype::comparator::ComparisonResult;
use mago_codex::ttype::comparator::union_comparator;
use mago_codex::ttype::expander;
use mago_codex::ttype::expander::StaticClassType;
use mago_codex::ttype::expander::TypeExpansionOptions;
use mago_codex::ttype::get_never;
use mago_codex::ttype::template::TemplateBound;
use mago_codex::ttype::template::TemplateResult;
use mago_codex::ttype::template::inferred_type_replacer;
use mago_codex::ttype::union::TUnion;
use mago_word::WordMap;
use mago_word::empty_word;

use crate::context::Context;
use crate::invocation::Invocation;

/// Resolves a type resulting from an invocation.
pub fn resolve_invocation_type<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    invocation_type: TUnion,
) -> TUnion
where
    A: Arena,
{
    let mut template_result = Cow::Borrowed(template_result);

    'populate_templates: {
        if let Some(function_like_identifier) = invocation.target.get_function_like_identifier() {
            let generic_parent = match function_like_identifier {
                FunctionLikeIdentifier::Method(class, method) => GenericParent::FunctionLike((*class, *method)),
                FunctionLikeIdentifier::Function(function) => GenericParent::FunctionLike((empty_word(), *function)),
                _ => {
                    break 'populate_templates;
                }
            };

            let method_templates = invocation.target.get_template_types();

            let all_template_names: Vec<_> = method_templates
                .map(|m| m.keys().copied().collect::<Vec<_>>())
                .unwrap_or_default()
                .into_iter()
                .chain(template_result.template_types.keys().copied())
                .collect();

            for template_name in all_template_names {
                let has_bound_for_method = template_result
                    .lower_bounds
                    .get(&template_name)
                    .and_then(|bounds| bounds.get(&generic_parent))
                    .is_some_and(|bounds| !bounds.is_empty());

                let method_parents: Vec<_> = method_templates
                    .and_then(|m| m.get(&template_name))
                    .map(|t| vec![&t.defining_entity])
                    .unwrap_or_default();

                let result_parents: Vec<_> = template_result
                    .template_types
                    .get(&template_name)
                    .map(|v| v.iter().map(|t| &t.defining_entity).collect())
                    .unwrap_or_default();

                let has_bound_for_template_parent =
                    method_parents.iter().chain(result_parents.iter()).any(|constraint_parent| {
                        template_result
                            .lower_bounds
                            .get(&template_name)
                            .and_then(|bounds| bounds.get(*constraint_parent))
                            .is_some_and(|bounds| !bounds.is_empty())
                    });

                if !has_bound_for_method && !has_bound_for_template_parent {
                    let mut owned_template_result = template_result.into_owned();

                    owned_template_result
                        .lower_bounds
                        .entry(template_name)
                        .or_default()
                        .insert(generic_parent, vec![TemplateBound::new(get_never(), 1, None, None)]);

                    template_result = Cow::Owned(owned_template_result);
                }
            }
        }
    }

    resolve_union(context, invocation, &template_result, parameters, invocation_type)
}

fn resolve_union<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    union_to_resolve: TUnion,
) -> TUnion
where
    A: Arena,
{
    let mut resulting_union = union_to_resolve;
    let mut resulting_atomics = Vec::with_capacity(resulting_union.types.len());
    for atomic_to_resolve in resulting_union.types.into_owned() {
        let return_atomics = resolve_atomic(context, invocation, template_result, parameters, atomic_to_resolve);
        resulting_atomics.extend(return_atomics);
    }

    resulting_union.types = Cow::Owned(resulting_atomics);

    if !template_result.lower_bounds.is_empty() || resulting_union.has_template_types() {
        // Replace templates first so derived types (e.g. `template-type<T, ...>`)
        // see concrete object/target types before expansion runs their resolution logic.
        // Running expansion first would eagerly walk the abstract `T`'s constraint and lose the substitution site.
        resulting_union = inferred_type_replacer::replace(&resulting_union, template_result, context.codebase);

        expander::expand_union(
            context.codebase,
            &mut resulting_union,
            &TypeExpansionOptions { expand_templates: false, ..Default::default() },
        );
    }

    let static_class_type;
    let parent_class;
    let self_class;
    let function_is_final;
    let allow_mixin_static_rebind;

    if let Some(method_context) = invocation.target.get_method_context() {
        static_class_type = method_context.class_type.clone();
        allow_mixin_static_rebind = method_context.declaring_object_type.is_some();
        parent_class = method_context.class_like_metadata.direct_parent_class;
        self_class = Some(method_context.class_like_metadata.name);
        function_is_final = invocation
            .target
            .get_function_like_metadata()
            .and_then(|metadata| metadata.method_metadata.as_ref())
            .is_some_and(|metadata| metadata.is_final);

        if let Some(declaring_method_id) = &method_context.declaring_method_id {
            let declaring_class_name = declaring_method_id.get_class_name();
            if declaring_class_name != method_context.class_like_metadata.name
                && let Some(declaring_class_meta) = context.codebase.get_class_like(declaring_class_name.as_bytes())
                && declaring_class_meta.kind.is_trait()
            {
                let mut new_atomics = Vec::with_capacity(resulting_union.types.len());
                for atomic in resulting_union.types.as_ref() {
                    match atomic {
                        TAtomic::Object(TObject::Named(named_object))
                            if named_object.name.as_bytes().eq_ignore_ascii_case(declaring_class_name.as_bytes()) =>
                        {
                            let mut new_object = named_object.clone();
                            new_object.name = method_context.class_like_metadata.name;
                            new_atomics.push(TAtomic::Object(TObject::Named(new_object)));
                        }
                        _ => new_atomics.push(atomic.clone()),
                    }
                }

                resulting_union.types = Cow::Owned(new_atomics);
            }
        }
    } else {
        static_class_type = StaticClassType::default();
        parent_class = None;
        self_class = None;
        function_is_final = false;
        allow_mixin_static_rebind = false;
    }

    let has_lexically_bound_parameter = resulting_union
        .get_all_child_nodes()
        .into_iter()
        .any(|node| matches!(node, TypeRef::Atomic(TAtomic::Variable(_))));
    if !has_lexically_bound_parameter {
        expander::expand_union(
            context.codebase,
            &mut resulting_union,
            &TypeExpansionOptions {
                expand_templates: false,
                expand_generic: true,
                self_class,
                static_class_type,
                parent_class,
                function_is_final,
                allow_mixin_static_rebind,
                ..Default::default()
            },
        );
    }

    resulting_union
}

fn resolve_atomic<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    atomic_to_resolve: TAtomic,
) -> Vec<TAtomic>
where
    A: Arena,
{
    if !matches!(&atomic_to_resolve, TAtomic::Variable(_) | TAtomic::Conditional(_) | TAtomic::Derived(_))
        && !atomic_to_resolve
            .get_all_child_nodes()
            .into_iter()
            .any(|node| matches!(node, TypeRef::Atomic(TAtomic::Variable(_))))
    {
        return vec![atomic_to_resolve];
    }

    match atomic_to_resolve {
        TAtomic::Variable(variable) => {
            if variable.as_bytes().eq_ignore_ascii_case(b"$this")
                && let Some(method_context) = invocation.target.get_method_context()
                && let StaticClassType::Object(this_type) = &method_context.class_type
            {
                return vec![TAtomic::Object(this_type.clone())];
            }

            parameters
                .get(&variable)
                .map(|argument_type| {
                    inferred_type_replacer::replace(argument_type, template_result, context.codebase).types.into_owned()
                })
                .unwrap_or_else(|| vec![TAtomic::Mixed(TMixed::new())])
        }
        TAtomic::Conditional(conditional) => {
            resolve_conditional(context, invocation, template_result, parameters, conditional)
        }
        TAtomic::Derived(mut derived) => {
            resolve_derived(context, invocation, template_result, parameters, &mut derived);

            vec![TAtomic::Derived(derived)]
        }
        TAtomic::Array(mut array) => {
            match &mut array {
                TArray::List(list) => {
                    *std::sync::Arc::make_mut(&mut list.element_type) =
                        resolve_union(context, invocation, template_result, parameters, (*list.element_type).clone());

                    if let Some(known_elements) = &mut list.known_elements {
                        for (_, element_type) in known_elements.values_mut() {
                            *element_type =
                                resolve_union(context, invocation, template_result, parameters, element_type.clone());
                        }
                    }
                }
                TArray::Keyed(keyed) => {
                    if let Some((key_type, value_type)) = &mut keyed.parameters {
                        *std::sync::Arc::make_mut(key_type) =
                            resolve_union(context, invocation, template_result, parameters, (**key_type).clone());
                        *std::sync::Arc::make_mut(value_type) =
                            resolve_union(context, invocation, template_result, parameters, (**value_type).clone());
                    }

                    if let Some(known_items) = &mut keyed.known_items {
                        for (_, item_type) in known_items.values_mut() {
                            *item_type =
                                resolve_union(context, invocation, template_result, parameters, item_type.clone());
                        }
                    }
                }
            }

            vec![TAtomic::Array(array)]
        }
        TAtomic::Iterable(mut iterable) => {
            *iterable.get_key_type_mut() =
                resolve_union(context, invocation, template_result, parameters, iterable.get_key_type().clone());
            *iterable.get_value_type_mut() =
                resolve_union(context, invocation, template_result, parameters, iterable.get_value_type().clone());
            resolve_intersection_types(
                context,
                invocation,
                template_result,
                parameters,
                iterable.get_intersection_types_mut(),
            );

            vec![TAtomic::Iterable(iterable)]
        }
        TAtomic::Object(mut object) => {
            match &mut object {
                TObject::Named(named) => {
                    if let Some(type_parameters) = named.get_type_parameters_mut() {
                        for type_parameter in type_parameters {
                            *type_parameter =
                                resolve_union(context, invocation, template_result, parameters, type_parameter.clone());
                        }
                    }
                }
                TObject::WithProperties(shape) => {
                    for (_, property_type) in shape.known_properties.values_mut() {
                        *property_type =
                            resolve_union(context, invocation, template_result, parameters, property_type.clone());
                    }
                }
                _ => {}
            }

            resolve_intersection_types(
                context,
                invocation,
                template_result,
                parameters,
                object.get_intersection_types_mut(),
            );

            vec![TAtomic::Object(object)]
        }
        TAtomic::Callable(mut callable) => {
            if let TCallable::Signature(signature) = &mut callable {
                let mut scoped_parameters = parameters.clone();
                for parameter in signature.get_parameters() {
                    if let Some(parameter_name) = parameter.get_name() {
                        scoped_parameters
                            .insert(parameter_name.0, TUnion::from_atomic(TAtomic::Variable(parameter_name.0)));
                    }
                }

                for parameter in signature.get_parameters_mut() {
                    if let Some(parameter_type) = parameter.get_type_signature_mut() {
                        *parameter_type = resolve_union(
                            context,
                            invocation,
                            template_result,
                            &scoped_parameters,
                            parameter_type.clone(),
                        );
                    }
                }

                if let Some(return_type) = signature.get_return_type_mut() {
                    *return_type =
                        resolve_union(context, invocation, template_result, &scoped_parameters, return_type.clone());
                }

                for constraint in &mut signature.constraints {
                    constraint.input_type = Arc::new(resolve_union(
                        context,
                        invocation,
                        template_result,
                        &scoped_parameters,
                        (*constraint.input_type).clone(),
                    ));
                    constraint.parameter_type = Arc::new(resolve_union(
                        context,
                        invocation,
                        template_result,
                        &scoped_parameters,
                        (*constraint.parameter_type).clone(),
                    ));
                }
            }

            vec![TAtomic::Callable(callable)]
        }
        TAtomic::GenericParameter(mut generic) => {
            generic.constraint = std::sync::Arc::new(resolve_union(
                context,
                invocation,
                template_result,
                parameters,
                (*generic.constraint).clone(),
            ));
            resolve_intersection_types(
                context,
                invocation,
                template_result,
                parameters,
                generic.intersection_types.as_mut(),
            );

            vec![TAtomic::GenericParameter(generic)]
        }
        TAtomic::Reference(mut reference) => {
            if let TReference::Symbol { parameters: type_parameters, intersection_types, .. } = &mut reference {
                if let Some(type_parameters) = type_parameters {
                    for type_parameter in type_parameters {
                        *type_parameter =
                            resolve_union(context, invocation, template_result, parameters, type_parameter.clone());
                    }
                }

                resolve_intersection_types(
                    context,
                    invocation,
                    template_result,
                    parameters,
                    intersection_types.as_mut(),
                );
            }

            vec![TAtomic::Reference(reference)]
        }
        TAtomic::Scalar(TScalar::ClassLikeString(class_string)) => {
            resolve_class_like_string(context, invocation, template_result, parameters, class_string)
        }
        atomic => vec![atomic],
    }
}

fn resolve_intersection_types<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    intersection_types: Option<&mut Vec<TAtomic>>,
) where
    A: Arena,
{
    let Some(intersection_types) = intersection_types else {
        return;
    };

    *intersection_types = resolve_union(
        context,
        invocation,
        template_result,
        parameters,
        TUnion::from_vec(std::mem::take(intersection_types)),
    )
    .types
    .into_owned();
}

fn resolve_class_like_string<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    class_string: TClassLikeString,
) -> Vec<TAtomic>
where
    A: Arena,
{
    let (kind, constraint, generic) = match class_string {
        TClassLikeString::OfType { kind, constraint } => (kind, constraint, None),
        TClassLikeString::Generic { kind, parameter_name, defining_entity, constraint } => {
            (kind, constraint, Some((parameter_name, defining_entity)))
        }
        class_string => return vec![TAtomic::Scalar(TScalar::ClassLikeString(class_string))],
    };

    resolve_union(
        context,
        invocation,
        template_result,
        parameters,
        TUnion::from_vec(vec![Arc::unwrap_or_clone(constraint)]),
    )
    .types
    .into_owned()
    .into_iter()
    .map(|constraint| {
        let class_string = if let Some((parameter_name, defining_entity)) = generic {
            TClassLikeString::generic(kind, parameter_name, defining_entity, constraint)
        } else {
            TClassLikeString::of_type(kind, constraint)
        };

        TAtomic::Scalar(TScalar::ClassLikeString(class_string))
    })
    .collect()
}

fn resolve_derived<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    derived: &mut TDerived,
) where
    A: Arena,
{
    match derived {
        TDerived::KeyOf(key_of) => {
            *key_of.get_target_type_mut() =
                resolve_union(context, invocation, template_result, parameters, key_of.get_target_type().clone());
        }
        TDerived::ValueOf(value_of) => {
            *value_of.get_target_type_mut() =
                resolve_union(context, invocation, template_result, parameters, value_of.get_target_type().clone());
        }
        TDerived::IntMask(int_mask) => {
            for value in int_mask.get_values_mut() {
                *value = resolve_union(context, invocation, template_result, parameters, value.clone());
            }
        }
        TDerived::IntMaskOf(int_mask_of) => {
            *int_mask_of.get_target_type_mut() =
                resolve_union(context, invocation, template_result, parameters, int_mask_of.get_target_type().clone());
        }
        TDerived::PropertiesOf(properties_of) => {
            *properties_of.get_target_type_mut() = resolve_union(
                context,
                invocation,
                template_result,
                parameters,
                properties_of.get_target_type().clone(),
            );
        }
        TDerived::IndexAccess(index_access) => {
            *index_access.get_target_type_mut() =
                resolve_union(context, invocation, template_result, parameters, index_access.get_target_type().clone());
            *index_access.get_index_type_mut() =
                resolve_union(context, invocation, template_result, parameters, index_access.get_index_type().clone());
        }
        TDerived::New(new_type) => {
            *new_type.get_target_type_mut() =
                resolve_union(context, invocation, template_result, parameters, new_type.get_target_type().clone());
        }
        TDerived::TemplateType(template_type) => {
            *template_type.get_object_mut() =
                resolve_union(context, invocation, template_result, parameters, template_type.get_object().clone());
            *template_type.get_class_name_mut() =
                resolve_union(context, invocation, template_result, parameters, template_type.get_class_name().clone());
            *template_type.get_template_name_mut() = resolve_union(
                context,
                invocation,
                template_result,
                parameters,
                template_type.get_template_name().clone(),
            );
        }
        TDerived::Intersection(intersection) => {
            let resolved_base =
                resolve_union(context, invocation, template_result, parameters, intersection.get_base_type().clone());
            *intersection.get_base_type_mut() = resolved_base;
            resolve_intersection_types(
                context,
                invocation,
                template_result,
                parameters,
                intersection.get_intersection_types_mut(),
            );
        }
    }
}

fn resolve_conditional<'ctx, 'arena, A>(
    context: &Context<'ctx, 'arena, A>,
    invocation: &Invocation<'ctx, '_, 'arena>,
    template_result: &TemplateResult,
    parameters: &WordMap<TUnion>,
    conditional: TConditional,
) -> Vec<TAtomic>
where
    A: Arena,
{
    let subject = resolve_union(context, invocation, template_result, parameters, (*conditional.subject).clone());
    let target = resolve_union(context, invocation, template_result, parameters, (*conditional.target).clone());
    let then_type = resolve_union(context, invocation, template_result, parameters, (*conditional.then).clone());
    let otherwise_type =
        resolve_union(context, invocation, template_result, parameters, (*conditional.otherwise).clone());
    let negated = conditional.negated;

    let subject = inferred_type_replacer::replace(&subject, template_result, context.codebase);
    let target = inferred_type_replacer::replace(&target, template_result, context.codebase);

    if !subject.is_never() {
        let mut comparison_result = ComparisonResult::new();
        let subject_is_contained = union_comparator::is_contained_by(
            context.codebase,
            &subject,
            &target,
            false,
            false,
            true,
            &mut comparison_result,
        );

        let are_int_float_disjoint = if target.is_single() && subject.is_single() {
            matches!(
                (subject.effective_int_or_float(), target.effective_int_or_float()),
                (Some(true), Some(false)) | (Some(false), Some(true))
            )
        } else {
            false
        };

        let are_disjoint = are_int_float_disjoint
            || !union_comparator::can_expression_types_be_identical(context.codebase, &subject, &target, false, false);

        if are_disjoint {
            return if negated { then_type.types.into_owned() } else { otherwise_type.types.into_owned() };
        }

        if subject_is_contained {
            return if negated { otherwise_type.types.into_owned() } else { then_type.types.into_owned() };
        }
    }

    add_union_type(then_type, &otherwise_type, context.codebase, CombinerOptions::default()).types.into_owned()
}