//! Global scope built-ins

use crate::avm2::activation::Activation;
use crate::avm2::class::Class;
use crate::avm2::domain::Domain;
use crate::avm2::method::NativeMethod;
use crate::avm2::names::{Namespace, QName};
use crate::avm2::object::{
    ClassObject, DomainObject, FunctionObject, Object, ScriptObject, TObject,
};
use crate::avm2::scope::Scope;
use crate::avm2::script::Script;
use crate::avm2::string::AvmString;
use crate::avm2::value::Value;
use crate::avm2::Error;
use gc_arena::{Collect, GcCell, MutationContext};

mod array;
mod boolean;
mod class;
mod flash;
mod function;
mod global_scope;
mod int;
mod math;
mod namespace;
mod number;
mod object;
mod regexp;
mod string;
mod r#uint;
mod xml;
mod xml_list;

const NS_RUFFLE_INTERNAL: &str = "https://ruffle.rs/AS3/impl/";

fn trace<'gc>(
    activation: &mut Activation<'_, 'gc, '_>,
    _this: Option<Object<'gc>>,
    args: &[Value<'gc>],
) -> Result<Value<'gc>, Error> {
    let mut message = String::new();
    if !args.is_empty() {
        message.push_str(&args[0].clone().coerce_to_string(activation)?);
        for arg in &args[1..] {
            message.push(' ');
            message.push_str(&arg.clone().coerce_to_string(activation)?);
        }
    }

    activation.context.log.avm_trace(&message);

    Ok(Value::Undefined)
}

fn is_finite<'gc>(
    activation: &mut Activation<'_, 'gc, '_>,
    _this: Option<Object<'gc>>,
    args: &[Value<'gc>],
) -> Result<Value<'gc>, Error> {
    if let Some(val) = args.get(0) {
        Ok(val.coerce_to_number(activation)?.is_finite().into())
    } else {
        Ok(false.into())
    }
}

fn is_nan<'gc>(
    activation: &mut Activation<'_, 'gc, '_>,
    _this: Option<Object<'gc>>,
    args: &[Value<'gc>],
) -> Result<Value<'gc>, Error> {
    if let Some(val) = args.get(0) {
        Ok(val.coerce_to_number(activation)?.is_nan().into())
    } else {
        Ok(true.into())
    }
}

/// This structure represents all system builtins' prototypes.
#[derive(Clone, Collect)]
#[collect(no_drop)]
pub struct SystemPrototypes<'gc> {
    pub object: Object<'gc>,
    pub function: Object<'gc>,
    pub class: Object<'gc>,
    pub global: Object<'gc>,
    pub string: Object<'gc>,
    pub boolean: Object<'gc>,
    pub number: Object<'gc>,
    pub int: Object<'gc>,
    pub uint: Object<'gc>,
    pub namespace: Object<'gc>,
    pub array: Object<'gc>,
    pub movieclip: Object<'gc>,
    pub framelabel: Object<'gc>,
    pub scene: Object<'gc>,
    pub application_domain: Object<'gc>,
    pub event: Object<'gc>,
    pub video: Object<'gc>,
    pub xml: Object<'gc>,
    pub xml_list: Object<'gc>,
    pub display_object: Object<'gc>,
    pub shape: Object<'gc>,
    pub point: Object<'gc>,
    pub textfield: Object<'gc>,
    pub textformat: Object<'gc>,
    pub graphics: Object<'gc>,
    pub loaderinfo: Object<'gc>,
    pub bytearray: Object<'gc>,
    pub stage: Object<'gc>,
    pub sprite: Object<'gc>,
    pub simplebutton: Object<'gc>,
    pub regexp: Object<'gc>,
}

impl<'gc> SystemPrototypes<'gc> {
    /// Construct a minimal set of system prototypes necessary for
    /// bootstrapping player globals.
    ///
    /// All other system prototypes aside from the three given here will be set
    /// to the empty object also handed to this function. It is the caller's
    /// responsibility to instantiate each class and replace the empty object
    /// with that.
    fn new(
        object: Object<'gc>,
        function: Object<'gc>,
        class: Object<'gc>,
        empty: Object<'gc>,
    ) -> Self {
        SystemPrototypes {
            object,
            function,
            class,
            global: empty,
            string: empty,
            boolean: empty,
            number: empty,
            int: empty,
            uint: empty,
            namespace: empty,
            array: empty,
            movieclip: empty,
            framelabel: empty,
            scene: empty,
            application_domain: empty,
            event: empty,
            video: empty,
            xml: empty,
            xml_list: empty,
            display_object: empty,
            shape: empty,
            point: empty,
            textfield: empty,
            textformat: empty,
            graphics: empty,
            loaderinfo: empty,
            bytearray: empty,
            stage: empty,
            sprite: empty,
            simplebutton: empty,
            regexp: empty,
        }
    }
}

/// This structure represents all system builtins' constructors.
#[derive(Clone, Collect)]
#[collect(no_drop)]
pub struct SystemConstructors<'gc> {
    pub object: Object<'gc>,
    pub function: Object<'gc>,
    pub class: Object<'gc>,
    pub global: Object<'gc>,
    pub string: Object<'gc>,
    pub boolean: Object<'gc>,
    pub number: Object<'gc>,
    pub int: Object<'gc>,
    pub uint: Object<'gc>,
    pub namespace: Object<'gc>,
    pub array: Object<'gc>,
    pub movieclip: Object<'gc>,
    pub framelabel: Object<'gc>,
    pub scene: Object<'gc>,
    pub application_domain: Object<'gc>,
    pub event: Object<'gc>,
    pub video: Object<'gc>,
    pub xml: Object<'gc>,
    pub xml_list: Object<'gc>,
    pub display_object: Object<'gc>,
    pub shape: Object<'gc>,
    pub point: Object<'gc>,
    pub textfield: Object<'gc>,
    pub textformat: Object<'gc>,
    pub graphics: Object<'gc>,
    pub loaderinfo: Object<'gc>,
    pub bytearray: Object<'gc>,
    pub stage: Object<'gc>,
    pub sprite: Object<'gc>,
    pub simplebutton: Object<'gc>,
    pub regexp: Object<'gc>,
}

impl<'gc> SystemConstructors<'gc> {
    /// Construct a minimal set of system prototypes necessary for
    /// bootstrapping player globals.
    ///
    /// All other system prototypes aside from the three given here will be set
    /// to the empty object also handed to this function. It is the caller's
    /// responsibility to instantiate each class and replace the empty object
    /// with that.
    fn new(
        object: Object<'gc>,
        function: Object<'gc>,
        class: Object<'gc>,
        empty: Object<'gc>,
    ) -> Self {
        SystemConstructors {
            object,
            function,
            class,
            global: empty,
            string: empty,
            boolean: empty,
            number: empty,
            int: empty,
            uint: empty,
            namespace: empty,
            array: empty,
            movieclip: empty,
            framelabel: empty,
            scene: empty,
            application_domain: empty,
            event: empty,
            video: empty,
            xml: empty,
            xml_list: empty,
            display_object: empty,
            shape: empty,
            point: empty,
            textfield: empty,
            textformat: empty,
            graphics: empty,
            loaderinfo: empty,
            bytearray: empty,
            stage: empty,
            sprite: empty,
            simplebutton: empty,
            regexp: empty,
        }
    }
}

/// Add a free-function builtin to the global scope.
fn function<'gc>(
    mc: MutationContext<'gc, '_>,
    package: impl Into<AvmString<'gc>>,
    name: impl Into<AvmString<'gc>>,
    nf: NativeMethod,
    fn_proto: Object<'gc>,
    mut domain: Domain<'gc>,
    script: Script<'gc>,
) -> Result<(), Error> {
    let name = QName::new(Namespace::package(package), name);
    let as3fn = FunctionObject::from_method_and_proto(mc, nf.into(), None, fn_proto, None).into();
    domain.export_definition(name.clone(), script, mc)?;
    script
        .init()
        .1
        .install_dynamic_property(mc, name, as3fn)
        .unwrap();

    Ok(())
}

/// Add a class builtin with prototype methods to the global scope.
///
/// Since the function has to return a normal prototype object in this case, we
/// have to construct a constructor to go along with it, as if we had called
/// `install_foreign_trait` with such a class.
fn dynamic_class<'gc>(
    mc: MutationContext<'gc, '_>,
    constr: Object<'gc>,
    mut domain: Domain<'gc>,
    script: Script<'gc>,
) -> Result<(), Error> {
    let class = constr
        .as_class()
        .ok_or("Attempted to create builtin dynamic class without class on it's constructor!")?;
    let name = class.read().name().clone();

    script
        .init()
        .1
        .install_const(mc, name.clone(), 0, constr.into());
    domain.export_definition(name, script, mc)
}

/// Add a class builtin to the global scope.
///
/// This function returns a prototype which may be stored in `SystemPrototypes`.
/// The `custom_derive` is used to select a particular `TObject` impl, or you
/// can use `None` to indicate that this class does not change host object
/// impls.
fn class<'gc>(
    activation: &mut Activation<'_, 'gc, '_>,
    class_def: GcCell<'gc, Class<'gc>>,
    mut domain: Domain<'gc>,
    script: Script<'gc>,
) -> Result<(Object<'gc>, Object<'gc>), Error> {
    let mut global = script.init().1;
    let global_scope = Scope::push_scope(
        global.get_scope(activation.context.gc_context),
        global,
        activation.context.gc_context,
    );

    let class_read = class_def.read();
    let super_class = if let Some(sc_name) = class_read.super_class_name() {
        let super_name = global
            .resolve_multiname(sc_name)?
            .unwrap_or_else(|| QName::dynamic_name("Object"));

        let super_class: Result<Object<'gc>, Error> = global
            .get_property(global, &super_name, activation)?
            .coerce_to_object(activation)
            .map_err(|_e| {
                format!("Could not resolve superclass {:?}", super_name.local_name()).into()
            });

        Some(super_class?)
    } else {
        None
    };

    let class_name = class_read.name().clone();
    drop(class_read);

    let mut constr =
        ClassObject::from_class(activation, class_def, super_class, Some(global_scope))?;
    global.install_const(
        activation.context.gc_context,
        class_name.clone(),
        0,
        constr.into(),
    );
    domain.export_definition(class_name, script, activation.context.gc_context)?;

    let proto = constr
        .get_property(
            constr,
            &QName::new(Namespace::public(), "prototype"),
            activation,
        )?
        .coerce_to_object(activation)?;

    Ok((constr, proto))
}

/// Add a builtin constant to the global scope.
fn constant<'gc>(
    mc: MutationContext<'gc, '_>,
    package: impl Into<AvmString<'gc>>,
    name: impl Into<AvmString<'gc>>,
    value: Value<'gc>,
    mut domain: Domain<'gc>,
    script: Script<'gc>,
) -> Result<(), Error> {
    let name = QName::new(Namespace::package(package), name);
    domain.export_definition(name.clone(), script, mc)?;
    script.init().1.install_const(mc, name, 0, value);

    Ok(())
}

macro_rules! avm2_system_class {
    ($field:ident, $activation:ident, $class:expr, $domain:expr, $script:expr) => {
        let (constr, proto) = class($activation, $class, $domain, $script)?;

        let sc = $activation.avm2().system_constructors.as_mut().unwrap();
        sc.$field = constr;

        let sp = $activation.avm2().system_prototypes.as_mut().unwrap();
        sp.$field = proto;
    };
}

/// Initialize the player global domain.
///
/// This should be called only once, to construct the global scope of the
/// player. It will return a list of prototypes it has created, which should be
/// stored on the AVM. All relevant declarations will also be attached to the
/// given domain.
pub fn load_player_globals<'gc>(
    activation: &mut Activation<'_, 'gc, '_>,
    domain: Domain<'gc>,
) -> Result<(), Error> {
    let mc = activation.context.gc_context;
    let gs = DomainObject::from_early_domain(mc, domain);
    let script = Script::empty_script(mc, gs);

    // public / root package
    //
    // We have to do this particular dance so that we have Object methods whose
    // functions have call/apply in their prototypes, and that Function is also
    // a subclass of Object.
    let object_proto = object::create_proto(activation);
    let fn_proto = function::create_proto(activation, object_proto);

    let (mut object_constr, object_cinit) =
        object::fill_proto(activation, gs, object_proto, fn_proto)?;
    let (mut function_constr, function_cinit) =
        function::fill_proto(activation, gs, fn_proto, object_constr)?;

    let (mut class_constr, class_proto, class_cinit) =
        class::create_class(activation, gs, object_constr, object_proto, fn_proto)?;

    dynamic_class(mc, object_constr, domain, script)?;
    dynamic_class(mc, function_constr, domain, script)?;
    dynamic_class(mc, class_constr, domain, script)?;

    // At this point, we need at least a partial set of system prototypes in
    // order to continue initializing the player. The rest of the prototypes
    // are set to a bare object until we have a chance to initialize them.
    activation.context.avm2.system_prototypes = Some(SystemPrototypes::new(
        object_proto,
        fn_proto,
        class_proto,
        ScriptObject::bare_object(mc),
    ));

    activation.context.avm2.system_constructors = Some(SystemConstructors::new(
        object_constr,
        function_constr,
        class_constr,
        ScriptObject::bare_object(mc),
    ));

    // We can now run all of the steps that would ordinarily be run
    // automatically had we not been so early in VM setup. This means things
    // like installing constructor traits and running class initializers, which
    // usually are done in the associated constructor for `ClassObject`.
    object_constr.install_traits(
        activation,
        object_constr.as_class().unwrap().read().class_traits(),
    )?;
    function_constr.install_traits(
        activation,
        function_constr.as_class().unwrap().read().class_traits(),
    )?;
    class_constr.install_traits(
        activation,
        class_constr.as_class().unwrap().read().class_traits(),
    )?;

    object_cinit.call(Some(object_constr), &[], activation, Some(object_constr))?;
    function_cinit.call(
        Some(function_constr),
        &[],
        activation,
        Some(function_constr),
    )?;
    class_cinit.call(Some(class_constr), &[], activation, Some(class_constr))?;

    avm2_system_class!(
        global,
        activation,
        global_scope::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(string, activation, string::create_class(mc), domain, script);
    avm2_system_class!(
        boolean,
        activation,
        boolean::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(number, activation, number::create_class(mc), domain, script);
    avm2_system_class!(int, activation, int::create_class(mc), domain, script);
    avm2_system_class!(uint, activation, uint::create_class(mc), domain, script);
    avm2_system_class!(
        namespace,
        activation,
        namespace::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(array, activation, array::create_class(mc), domain, script);

    // At this point we have to hide the fact that we had to create the player
    // globals scope *before* the `Object` class
    gs.set_proto(mc, activation.avm2().prototypes().global);

    function(mc, "", "trace", trace, fn_proto, domain, script)?;
    function(mc, "", "isFinite", is_finite, fn_proto, domain, script)?;
    function(mc, "", "isNaN", is_nan, fn_proto, domain, script)?;
    constant(mc, "", "undefined", Value::Undefined, domain, script)?;
    constant(mc, "", "null", Value::Null, domain, script)?;
    constant(mc, "", "NaN", f64::NAN.into(), domain, script)?;
    constant(mc, "", "Infinity", f64::INFINITY.into(), domain, script)?;

    class(activation, math::create_class(mc), domain, script)?;
    avm2_system_class!(regexp, activation, regexp::create_class(mc), domain, script);

    avm2_system_class!(xml, activation, xml::create_class(mc), domain, script);
    avm2_system_class!(
        xml_list,
        activation,
        xml_list::create_class(mc),
        domain,
        script
    );

    // package `flash.system`
    avm2_system_class!(
        application_domain,
        activation,
        flash::system::application_domain::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::system::system::create_class(mc),
        domain,
        script,
    )?;

    // package `flash.events`
    avm2_system_class!(
        event,
        activation,
        flash::events::event::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::events::ieventdispatcher::create_interface(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::events::eventdispatcher::create_class(mc),
        domain,
        script,
    )?;
    // package `flash.utils`
    avm2_system_class!(
        bytearray,
        activation,
        flash::utils::bytearray::create_class(mc),
        domain,
        script
    );

    //We also have to do this to the global scope, too.
    gs.as_application_domain()
        .unwrap()
        .init_default_domain_memory(activation)?;

    class(
        activation,
        flash::utils::endian::create_class(mc),
        domain,
        script,
    )?;

    class(
        activation,
        flash::utils::compression_algorithm::create_class(mc),
        domain,
        script,
    )?;

    function(
        mc,
        "flash.utils",
        "getTimer",
        flash::utils::get_timer,
        fn_proto,
        domain,
        script,
    )?;

    // package `flash.display`
    avm2_system_class!(
        display_object,
        activation,
        flash::display::displayobject::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(
        shape,
        activation,
        flash::display::shape::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::display::interactiveobject::create_class(mc),
        domain,
        script,
    )?;
    avm2_system_class!(
        simplebutton,
        activation,
        flash::display::simplebutton::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::display::displayobjectcontainer::create_class(mc),
        domain,
        script,
    )?;
    avm2_system_class!(
        sprite,
        activation,
        flash::display::sprite::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(
        movieclip,
        activation,
        flash::display::movieclip::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(
        framelabel,
        activation,
        flash::display::framelabel::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(
        scene,
        activation,
        flash::display::scene::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(
        graphics,
        activation,
        flash::display::graphics::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::display::jointstyle::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::display::linescalemode::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::display::capsstyle::create_class(mc),
        domain,
        script,
    )?;
    avm2_system_class!(
        loaderinfo,
        activation,
        flash::display::loaderinfo::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::display::actionscriptversion::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::display::swfversion::create_class(mc),
        domain,
        script,
    )?;
    avm2_system_class!(
        stage,
        activation,
        flash::display::stage::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::display::stagescalemode::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::display::stagealign::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::display::stagedisplaystate::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::display::stagequality::create_class(mc),
        domain,
        script,
    )?;

    // package `flash.geom`
    avm2_system_class!(
        point,
        activation,
        flash::geom::point::create_class(mc),
        domain,
        script
    );

    // package `flash.media`
    avm2_system_class!(
        video,
        activation,
        flash::media::video::create_class(mc),
        domain,
        script
    );

    // package `flash.text`
    avm2_system_class!(
        textfield,
        activation,
        flash::text::textfield::create_class(mc),
        domain,
        script
    );
    avm2_system_class!(
        textformat,
        activation,
        flash::text::textformat::create_class(mc),
        domain,
        script
    );
    class(
        activation,
        flash::text::textfieldautosize::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::text::textformatalign::create_class(mc),
        domain,
        script,
    )?;
    class(
        activation,
        flash::text::textfieldtype::create_class(mc),
        domain,
        script,
    )?;

    Ok(())
}