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#[cfg(engine)]
use crate::server::HtmlShell;
#[cfg(engine)]
use crate::utils::get_path_prefix_server;
use crate::{
    error_views::ErrorViews,
    i18n::{Locales, TranslationsManager},
    plugins::{PluginAction, Plugins},
    state::GlobalStateCreator,
    stores::MutableStore,
    template::{Entity, Forever, Template},
};
#[cfg(any(client, doc))]
use crate::{
    error_views::{ErrorContext, ErrorPosition},
    errors::ClientError,
};
use crate::{errors::PluginError, template::Capsule};
use crate::{stores::ImmutableStore, template::EntityMap};
use futures::Future;
#[cfg(any(client, doc))]
use std::marker::PhantomData;
#[cfg(engine)]
use std::pin::Pin;
#[cfg(any(client, doc))]
use std::rc::Rc;
use std::{any::TypeId, sync::Arc};
use std::{collections::HashMap, panic::PanicInfo};
use sycamore::prelude::Scope;
use sycamore::utils::hydrate::with_no_hydration_context;
use sycamore::web::{Html, SsrNode};
use sycamore::{
    prelude::{component, view},
    view::View,
};

/// The default index view, because some simple apps won't need anything fancy
/// here. The user should be able to provide the smallest possible amount of
/// information for their app to work.
static DFLT_INDEX_VIEW: &str = r#"
<html>
    <head>
        <meta charset="UTF-8" />
        <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    </head>
    <body>
        <div id="root"></div>
    </body>
</html>"#;
/// The default number of pages the page state store will allow before evicting
/// the oldest. Note: we don't allow an infinite number in development here
/// because that does actually get quite problematic after a few hours of
/// constant reloading and HSR (as in Firefox decides that opening the DevTools
/// is no longer allowed).
// TODO What's a sensible value here?
static DFLT_PSS_MAX_SIZE: usize = 25;

/// The different types of translations managers that can be stored. This allows
/// us to store dummy translations managers directly, without holding futures.
/// If this stores a full translations manager though, it will store it as a
/// `Future`, which is later evaluated.
#[cfg(engine)]
pub(crate) enum Tm<T: TranslationsManager> {
    Dummy(T),
    Full(Pin<Box<dyn Future<Output = T>>>),
}
#[cfg(engine)]
impl<T: TranslationsManager> std::fmt::Debug for Tm<T> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Tm").finish_non_exhaustive()
    }
}

/// An automatically implemented trait for asynchronous functions that return
/// instances of `TranslationsManager`. This is needed so we can store the
/// 'promise' of getting a translations manager in future by executing a stored
/// asynchronous function (because we don't want to take in the actual value,
/// which would require asynchronous initialization functions, which we
/// can't have in environments like the browser).
#[doc(hidden)]
pub trait TranslationsManagerGetter {
    type Output: TranslationsManager;
    fn call(&self) -> Box<dyn Future<Output = Self::Output>>;
}
impl<T, F, Fut> TranslationsManagerGetter for F
where
    T: TranslationsManager,
    F: Fn() -> Fut,
    Fut: Future<Output = T> + 'static,
{
    type Output = T;
    fn call(&self) -> Box<dyn Future<Output = Self::Output>> {
        Box::new(self())
    }
}

/// The options for constructing a Perseus app. This `struct` will tie
/// together all your code, declaring to Perseus where your templates,
/// error pages, static content, etc. are.
///
/// # Memory leaks
///
/// This `struct` internally stores all templates and capsules as static
/// references, since they will definitionally be required for the lifetime
/// of the app, and since this enables support for capsules created and
/// managed through a `lazy_static!`, a very convenient and efficient pattern.
///
/// However, this does mean that the methods on this `struct` for adding
/// templates and capsules perform `Box::leak` calls internally, creating
/// deliberate memory leaks. This would be ...
pub struct PerseusAppBase<G: Html, M: MutableStore, T: TranslationsManager> {
    /// The HTML ID of the root `<div>` element into which Perseus will be
    /// injected.
    pub(crate) root: String,
    /// A list of all the templates and capsules that the app uses.
    pub(crate) entities: EntityMap<G>,
    /// The app's error pages.
    #[cfg(client)]
    pub(crate) error_views: Option<Rc<ErrorViews<G>>>,
    #[cfg(engine)]
    pub(crate) error_views: Option<Arc<ErrorViews<G>>>,
    /// The maximum size for the page state store.
    pub(crate) pss_max_size: usize,
    /// The global state creator for the app.
    // This is wrapped in an `Arc` so we can pass it around on the engine-side (which is solely for
    // Actix's benefit...)
    #[cfg(engine)]
    pub(crate) global_state_creator: Arc<GlobalStateCreator>,
    /// The internationalization information for the app.
    pub(crate) locales: Locales,
    /// The static aliases the app serves.
    #[cfg(engine)]
    pub(crate) static_aliases: HashMap<String, String>,
    /// The plugins the app uses.
    #[cfg(engine)]
    pub(crate) plugins: Arc<Plugins>,
    #[cfg(client)]
    pub(crate) plugins: Rc<Plugins>,
    /// The app's immutable store.
    #[cfg(engine)]
    pub(crate) immutable_store: ImmutableStore,
    /// The HTML template that'll be used to render the app into. This must be
    /// static, but can be generated or sourced in any way. Note that this MUST
    /// contain a `<div>` with the `id` set to whatever the value of `self.root`
    /// is.
    pub(crate) index_view: String,
    /// The app's mutable store.
    #[cfg(engine)]
    pub(crate) mutable_store: M,
    /// The app's translations manager, expressed as a function yielding a
    /// `Future`. This is only ever needed on the server-side, and can't be set
    /// up properly on the client-side because we can't use futures in the
    /// app initialization in Wasm.
    #[cfg(engine)]
    pub(crate) translations_manager: Tm<T>,
    /// The location of the directory to use for static assets that will placed
    /// under the URL `/.perseus/static/`. By default, this is the `static/`
    /// directory at the root of your project. Note that the directory set
    /// here will only be used if it exists.
    #[cfg(engine)]
    pub(crate) static_dir: String,
    /// A handler for panics on the browser-side.
    #[cfg(any(client, doc))]
    #[allow(clippy::type_complexity)] // TODO Really?
    pub(crate) panic_handler: Option<Box<dyn Fn(&PanicInfo) + Send + Sync + 'static>>,
    /// A duplicate of the app's error handling function intended for panic
    /// handling. This must be extracted as an owned value and provided in a
    /// thread-safe manner to the panic hook system.
    ///
    /// This is in an `Arc` because panic hooks are `Fn`s, not `FnOnce`s.
    #[cfg(any(client, doc))]
    #[allow(clippy::type_complexity)]
    pub(crate) panic_handler_view: Arc<
        dyn Fn(Scope, ClientError, ErrorContext, ErrorPosition) -> (View<SsrNode>, View<G>)
            + Send
            + Sync,
    >,
    // We need this on the client-side to account for the unused type parameters
    #[cfg(any(client, doc))]
    _marker: PhantomData<(M, T)>,
}
impl<G: Html, M: MutableStore, T: TranslationsManager> std::fmt::Debug for PerseusAppBase<G, M, T> {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        // We have to do the commons, and then the target-gates separately (otherwise
        // Rust uses the dummy methods)
        let mut debug = f.debug_struct("PerseusAppBase");
        debug
            .field("root", &self.root)
            .field("entities", &self.entities)
            .field("error_views", &self.error_views)
            .field("pss_max_size", &self.pss_max_size)
            .field("locale", &self.locales)
            .field("plugins", &self.plugins)
            .field("index_view", &self.index_view);
        #[cfg(any(client, doc))]
        {
            return debug
                .field(
                    "panic_handler",
                    &self
                        .panic_handler
                        .as_ref()
                        .map(|_| "dyn Fn(&PanicInfo) + Send + Sync + 'static"),
                )
                .finish_non_exhaustive();
        }
        #[cfg(engine)]
        {
            return debug
                .field("global_state_creator", &self.global_state_creator)
                .field("mutable_store", &self.mutable_store)
                .field("translations_manager", &self.translations_manager)
                .field("static_dir", &self.static_dir)
                .field("static_aliases", &self.static_aliases)
                .field("immutable_store", &self.immutable_store)
                .finish_non_exhaustive();
        }
    }
}

// The usual implementation in which the default mutable store is used
// We don't need to have a similar one for the default translations manager
// because things are completely generic there
impl<G: Html, T: TranslationsManager> PerseusAppBase<G, FsMutableStore, T> {
    /// Creates a new instance of a Perseus app using the default
    /// filesystem-based mutable store (see [`FsMutableStore`]). For most apps,
    /// this will be sufficient. Note that this initializes the translations
    /// manager as a dummy (see [`FsTranslationsManager`]), and
    /// adds no templates or error pages.
    ///
    /// In development, you can get away with defining no error pages, but
    /// production apps (e.g. those created with `perseus deploy`) MUST set
    /// their own custom error pages.
    ///
    /// This is asynchronous because it creates a translations manager in the
    /// background.
    // It makes no sense to implement `Default` on this, so we silence Clippy deliberately
    #[cfg(engine)]
    #[allow(clippy::new_without_default)]
    pub fn new() -> Self {
        Self::new_with_mutable_store(FsMutableStore::new("./dist/mutable".to_string()))
    }
    /// Creates a new instance of a Perseus app using the default
    /// filesystem-based mutable store (see [`FsMutableStore`]). For most apps,
    /// this will be sufficient. Note that this initializes the translations
    /// manager as a dummy (see [`FsTranslationsManager`]), and
    /// adds no templates or error pages.
    ///
    /// In development, you can get away with defining no error pages, but
    /// production apps (e.g. those created with `perseus deploy`) MUST set
    /// their own custom error pages.
    ///
    /// This is asynchronous because it creates a translations manager in the
    /// background.
    // It makes no sense to implement `Default` on this, so we silence Clippy deliberately
    #[cfg(any(client, doc))]
    #[allow(clippy::new_without_default)]
    pub fn new() -> Self {
        Self::new_wasm()
    }
}
// If one's using the default translations manager, caching should be handled
// automatically for them
impl<G: Html, M: MutableStore> PerseusAppBase<G, M, FsTranslationsManager> {
    /// The same as `.locales_and_translations_manager()`, but this accepts a
    /// literal [`Locales`] `struct`, which means this can be used when you're
    /// using [`FsTranslationsManager`] but when you don't know if your app is
    /// using i18n or not (almost always middleware).
    pub fn locales_lit_and_translations_manager(mut self, locales: Locales) -> Self {
        #[cfg(engine)]
        let using_i18n = locales.using_i18n;

        self.locales = locales;
        // We only handle the translations manager on the server-side (it doesn't exist
        // on the client-side)
        #[cfg(engine)]
        {
            // If we're using i18n, do caching stuff
            // If not, use a dummy translations manager
            if using_i18n {
                // By default, all translations are cached
                let all_locales: Vec<String> = self
                    .locales
                    .get_all()
                    .iter()
                    // We have a `&&String` at this point, hence the double clone
                    .cloned()
                    .cloned()
                    .collect();
                let tm_fut = FsTranslationsManager::new(
                    crate::i18n::DFLT_TRANSLATIONS_DIR.to_string(),
                    all_locales,
                    crate::i18n::TRANSLATOR_FILE_EXT.to_string(),
                );
                self.translations_manager = Tm::Full(Box::pin(tm_fut));
            } else {
                self.translations_manager = Tm::Dummy(FsTranslationsManager::new_dummy());
            }
        }

        self
    }
    /// Sets the internationalization information for an app using the default
    /// translations manager ([`FsTranslationsManager`]). This handles locale
    /// caching and the like automatically for you, though you could
    /// alternatively use `.locales()` and `.translations_manager()`
    /// independently to customize various behaviors. This takes the same
    /// arguments as `.locales()`, so the first argument is the default
    /// locale (used as a fallback for users with no locale preferences set in
    /// their browsers), and the second is a list of other locales supported.
    ///
    /// If you're not using i18n, you don't need to call this function. If you
    /// for some reason do have to though (e.g. overriding some other
    /// preferences in middleware), use `.disable_i18n()`, not this, as
    /// you're very likely to shoot yourself in the foot! (If i18n is disabled,
    /// the default locale MUST be set to `xx-XX`, for example.)
    pub fn locales_and_translations_manager(self, default: &str, other: &[&str]) -> Self {
        let locales = Locales {
            default: default.to_string(),
            other: other.iter().map(|s| s.to_string()).collect(),
            using_i18n: true,
        };

        self.locales_lit_and_translations_manager(locales)
    }
}
// The base implementation, generic over the mutable store and translations
// manager
impl<G: Html, M: MutableStore, T: TranslationsManager> PerseusAppBase<G, M, T> {
    /// Creates a new instance of a Perseus app, with the default options and a
    /// customizable [`MutableStore`], using the default dummy
    /// [`FsTranslationsManager`] by default (though this can be changed).
    #[allow(unused_variables)]
    pub fn new_with_mutable_store(mutable_store: M) -> Self {
        Self {
            root: "root".to_string(),
            // We do initialize with no templates, because an app without templates is in theory
            // possible (and it's more convenient to call `.template()` for each one)
            entities: HashMap::new(),
            // We do offer default error views, but they'll panic if they're called for production
            // building
            error_views: None,
            pss_max_size: DFLT_PSS_MAX_SIZE,
            #[cfg(engine)]
            global_state_creator: Arc::new(GlobalStateCreator::default()),
            // By default, we'll disable i18n (as much as I may want more websites to support more
            // languages...)
            locales: Locales {
                default: "xx-XX".to_string(),
                other: Vec::new(),
                using_i18n: false,
            },
            // By default, we won't serve any static content outside the `static/` directory
            #[cfg(engine)]
            static_aliases: HashMap::new(),
            // By default, we won't use any plugins
            #[cfg(engine)]
            plugins: Arc::new(Plugins::new()),
            #[cfg(any(client, doc))]
            plugins: Rc::new(Plugins::new()),
            #[cfg(engine)]
            immutable_store: ImmutableStore::new("./dist".to_string()),
            #[cfg(engine)]
            mutable_store,
            #[cfg(engine)]
            translations_manager: Tm::Dummy(T::new_dummy()),
            // Many users won't need anything fancy in the index view, so we provide a default
            index_view: DFLT_INDEX_VIEW.to_string(),
            #[cfg(engine)]
            static_dir: "./static".to_string(),
            #[cfg(any(client, doc))]
            panic_handler: None,
            #[cfg(any(client, doc))]
            panic_handler_view: ErrorViews::unlocalized_development_default().take_panic_handler(),
            #[cfg(any(client, doc))]
            _marker: PhantomData,
        }
    }
    /// Internal function for Wasm initialization. This should never be called
    /// by the user!
    #[cfg(any(client, doc))]
    #[doc(hidden)]
    fn new_wasm() -> Self {
        Self {
            root: "root".to_string(),
            // We do initialize with no templates, because an app without templates is in theory
            // possible (and it's more convenient to call `.template()` for each one)
            entities: HashMap::new(),
            // We do offer default error pages, but they'll panic if they're called for production
            // building
            error_views: None,
            pss_max_size: DFLT_PSS_MAX_SIZE,
            // By default, we'll disable i18n (as much as I may want more websites to support more
            // languages...)
            locales: Locales {
                default: "xx-XX".to_string(),
                other: Vec::new(),
                using_i18n: false,
            },
            // By default, we won't use any plugins
            plugins: Rc::new(Plugins::new()),
            // Many users won't need anything fancy in the index view, so we provide a default
            index_view: DFLT_INDEX_VIEW.to_string(),
            panic_handler: None,
            panic_handler_view: ErrorViews::unlocalized_development_default().take_panic_handler(),
            _marker: PhantomData,
        }
    }

    // Setters (these all consume `self`)
    /// Sets the HTML ID of the `<div>` element at which to insert Perseus.
    /// In your index view, this should use [`PerseusRoot`].
    ///
    /// *Note:* if you're using string HTML, the `<div>` with this ID MUST look
    /// *exactly* like this: `<div id="some-id-here"></div>`, spacing and
    /// all!
    pub fn root(mut self, val: &str) -> Self {
        self.root = val.to_string();
        self
    }
    /// Sets the location of the directory storing static assets to be hosted
    /// under the URL `/.perseus/static/`. By default, this is `static/` at
    /// the root of your project.
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn static_dir(mut self, val: &str) -> Self {
        #[cfg(engine)]
        {
            self.static_dir = val.to_string();
        }
        self
    }
    /// Sets all the app's templates. This takes a vector of templates.
    ///
    /// Usually, it's preferred to run `.template()` once for each template,
    /// rather than manually constructing this more inconvenient type.
    pub fn templates(mut self, val: Vec<Template<G>>) -> Self {
        for template in val.into_iter() {
            self = self.template(template);
        }
        self
    }
    /// Adds a single new template to the app. This expects the output of
    /// a function that is generic over `G: Html`. If you have something with a
    /// predetermined type, like a `lazy_static!` that's using
    /// `PerseusNodeType`, you should use `.template_ref()` instead. For
    /// more information on the differences between the function and referrence
    /// patterns, see the book.
    ///
    /// See [`Template`] for further details.
    pub fn template(self, val: impl Into<Forever<Template<G>>>) -> Self {
        self.template_ref(val)
    }
    /// Adds a single new template to the app. This can accept either an owned
    /// [`Template`] or a static reference to one, as might be created by a
    /// `lazy_static!`. The latter would force you to specify the rendering
    /// backend type (`G`) manually, using a smart alias like
    /// `PerseusNodeType`. This method performs internal type coercions to make
    /// statics work neatly.
    ///
    /// If your templates come from functions like `get_template`, that are
    /// generic over `G: Html`, you can use `.template()`, to avoid having
    /// to specify `::<G>` manually.
    ///
    /// See [`Template`] for further details, and the book for further details
    /// on the differences between the function and reference patterns.
    pub fn template_ref<H: Html>(mut self, val: impl Into<Forever<Template<H>>>) -> Self {
        assert_eq!(
            TypeId::of::<G>(),
            TypeId::of::<H>(),
            "mismatched render backends"
        );
        let val = val.into();
        // SAFETY: We asserted that `G == H` above.
        let val: Forever<Template<G>> = unsafe { std::mem::transmute(val) };

        let entity: Forever<Entity<G>> = match val {
            Forever::Owned(capsule) => capsule.inner.into(),
            Forever::StaticRef(capsule_ref) => (&capsule_ref.inner).into(),
        };

        let path = entity.get_path();
        self.entities.insert(path, entity);
        self
    }
    // TODO
    // /// Sets all the app's capsules. This takes a vector of capsules.
    // ///
    // /// Usually, it's preferred to run `.capsule()` once for each capsule,
    // /// rather than manually constructing this more inconvenient type.
    // pub fn capsules(mut self, val: Vec<Capsule<G>>) -> Self {
    //     for capsule in val.into_iter() {
    //         self = self.capsule(capsule);
    //     }
    //     self
    // }
    /// Adds a single new capsule to the app. Like `.template()`, this expects
    /// the output of a function that is generic over `G: Html`. If you have
    /// something with a predetermined type, like a `lazy_static!` that's
    /// using `PerseusNodeType`, you should use `.capsule_ref()`
    /// instead. For more information on the differences between the function
    /// and reference patterns, see the book.
    ///
    /// See [`Capsule`] for further details.
    pub fn capsule<P: Clone + 'static>(self, val: impl Into<Forever<Capsule<G, P>>>) -> Self {
        self.capsule_ref(val)
    }
    /// Adds a single new capsule to the app. This behaves like
    /// `.template_ref()`, but for capsules.
    ///
    /// See [`Capsule`] for further details.
    pub fn capsule_ref<H: Html, P: Clone + 'static>(
        mut self,
        val: impl Into<Forever<Capsule<H, P>>>,
    ) -> Self {
        assert_eq!(
            TypeId::of::<G>(),
            TypeId::of::<H>(),
            "mismatched render backends"
        );
        let val = val.into();
        // Enforce that capsules must have defined fallbacks
        if val.fallback.is_none() {
            panic!(
                "capsule '{}' has no fallback (please register one)",
                val.inner.get_path()
            )
        }

        // SAFETY: We asserted that `G == H` above.
        let val: Forever<Capsule<G, P>> = unsafe { std::mem::transmute(val) };

        let entity: Forever<Entity<G>> = match val {
            Forever::Owned(capsule) => capsule.inner.into(),
            Forever::StaticRef(capsule_ref) => (&capsule_ref.inner).into(),
        };

        let path = entity.get_path();
        self.entities.insert(path, entity);
        self
    }
    /// Sets the app's error views. See [`ErrorViews`] for further details.
    // Internally, this will extract a copy of the main handler for panic
    // usage. Note that the default value of this is extracted from the default
    // error views.
    #[allow(unused_mut)]
    pub fn error_views(mut self, mut val: ErrorViews<G>) -> Self {
        #[cfg(any(client, doc))]
        {
            let panic_handler = val.take_panic_handler();
            self.error_views = Some(Rc::new(val));
            self.panic_handler_view = panic_handler;
        }
        #[cfg(engine)]
        {
            self.error_views = Some(Arc::new(val));
        }

        self
    }
    /// Sets the app's [`GlobalStateCreator`].
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn global_state_creator(mut self, val: GlobalStateCreator) -> Self {
        #[cfg(engine)]
        {
            self.global_state_creator = Arc::new(val);
        }
        self
    }
    /// Sets the locales information for the app. The first argument is the
    /// default locale (used as a fallback for users with no locale preferences
    /// set in their browsers), and the second is a list of other locales
    /// supported.
    ///
    /// Note that this does not update the translations manager, which must be
    /// done separately (if you're using [`FsTranslationsManager`], the default,
    /// you can use `.locales_and_translations_manager()` to set both at
    /// once).
    ///
    /// If you're not using i18n, you don't need to call this function. If you
    /// for some reason do have to though (e.g. overriding some other
    /// preferences in middleware), use `.disable_i18n()`, not this, as
    /// you're very likely to shoot yourself in the foot! (If i18n is disabled,
    /// the default locale MUST be set to `xx-XX`, for example.)
    pub fn locales(mut self, default: &str, other: &[&str]) -> Self {
        self.locales = Locales {
            default: default.to_string(),
            other: other.iter().map(|s| s.to_string()).collect(),
            using_i18n: true,
        };
        self
    }
    /// Sets the locales information directly based on an instance of
    /// [`Locales`]. Usually, end users will use `.locales()` instead for a
    /// friendlier interface.
    pub fn locales_lit(mut self, val: Locales) -> Self {
        self.locales = val;
        self
    }
    /// Sets the translations manager. If you're using the default translations
    /// manager ([`FsTranslationsManager`]), you can use
    /// `.locales_and_translations_manager()` to set this automatically
    /// based on the locales information. This takes a `Future<Output = T>`,
    /// where `T` is your translations manager's type.
    ///
    /// The reason that this takes a `Future` is to avoid the use of `.await` in
    /// your app definition code, which must be synchronous due to constraints
    /// of Perseus' browser-side systems. When your code is run on the
    /// server, the `Future` will be `.await`ed on, but in Wasm, it will be
    /// discarded and ignored, since the translations manager isn't needed in
    /// Wasm.
    ///
    /// This is generally intended for use with custom translations manager or
    /// specific use-cases with the default (mostly to do with custom caching
    /// behavior).
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn translations_manager(mut self, val: impl Future<Output = T> + 'static) -> Self {
        #[cfg(engine)]
        {
            self.translations_manager = Tm::Full(Box::pin(val));
        }
        self
    }
    /// Explicitly disables internationalization. You shouldn't ever need to
    /// call this, as it's the default, but you may want to if you're writing
    /// middleware that doesn't support i18n.
    pub fn disable_i18n(mut self) -> Self {
        self.locales = Locales {
            default: "xx-XX".to_string(),
            other: Vec::new(),
            using_i18n: false,
        };
        // All translations manager must implement this function, which is designed for
        // this exact purpose
        #[cfg(engine)]
        {
            self.translations_manager = Tm::Dummy(T::new_dummy());
        }
        self
    }
    /// Sets all the app's static aliases. This takes a map of URLs (e.g.
    /// `/file`) to resource paths, relative to the project directory (e.g.
    /// `style.css`). Generally, calling `.static_alias()` many times is
    /// preferred.
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn static_aliases(mut self, val: HashMap<String, String>) -> Self {
        #[cfg(engine)]
        {
            self.static_aliases = val;
        }
        self
    }
    /// Adds a single static alias. This takes a URL path (e.g. `/file`)
    /// followed by a path to a resource (which must be within the project
    /// directory, e.g. `style.css`).
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn static_alias(mut self, url: &str, resource: &str) -> Self {
        #[cfg(engine)]
        // We don't elaborate the alias to an actual filesystem path until the getter
        self.static_aliases
            .insert(url.to_string(), resource.to_string());
        self
    }
    /// Sets the plugins that the app will use. See [`Plugins`] for
    /// further details.
    pub fn plugins(mut self, val: Plugins) -> Self {
        #[cfg(any(client, doc))]
        {
            self.plugins = Rc::new(val);
        }
        #[cfg(engine)]
        {
            self.plugins = Arc::new(val);
        }

        self
    }
    /// Sets the [`MutableStore`] for the app to use, which you would change for
    /// some production server environments if you wanted to store build
    /// artifacts that can change at runtime in a place other than on the
    /// filesystem (created for serverless functions specifically).
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn mutable_store(mut self, val: M) -> Self {
        #[cfg(engine)]
        {
            self.mutable_store = val;
        }
        self
    }
    /// Sets the [`ImmutableStore`] for the app to use. You should almost never
    /// need to change this unless you're not working with the CLI.
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn immutable_store(mut self, val: ImmutableStore) -> Self {
        #[cfg(engine)]
        {
            self.immutable_store = val;
        }
        self
    }
    /// Sets the index view as a string. This should be used if you're using an
    /// `index.html` file or the like.
    ///
    /// Note: if possible, you should switch to using `.index_view()`, which
    /// uses a Sycamore view rather than an HTML string.
    pub fn index_view_str(mut self, val: &str) -> Self {
        self.index_view = val.to_string();
        self
    }
    /// Sets the index view using a Sycamore view, which avoids the need to
    /// write any HTML by hand whatsoever. Note that this must contain a
    /// `<head>` and `<body>` at a minimum.
    ///
    /// Warning: this view can't be reactive (yet). It will be rendered to a
    /// static string, which won't be hydrated.
    // The lifetime of the provided function doesn't need to be static, because we
    // render using it and then we're done with it
    pub fn index_view<'a>(mut self, f: impl Fn(Scope) -> View<SsrNode> + 'a) -> Self {
        // We need to render the index view without any hydration IDs (which would break
        // the HTML shell's interpolation mechanisms)
        let html_str = sycamore::render_to_string(|cx| with_no_hydration_context(|| f(cx)));
        self.index_view = html_str;

        self
    }
    /// Sets the maximum number of pages that can have their states stored in
    /// the page state store before the oldest will be evicted. If your app is
    /// taking up a substantial amount of memory in the browser because your
    /// page states are fairly large, making this smaller may help.
    ///
    /// By default, this is set to 25. Higher values may lead to memory
    /// difficulties in both development and production, and the poor user
    /// experience of a browser that's substantially slowed down.
    ///
    /// WARNING: any setting applied here will impact HSR in development! (E.g.
    /// setting this to 1 would mean your position would only be
    /// saved for the most recent page.)
    pub fn pss_max_size(mut self, val: usize) -> Self {
        self.pss_max_size = val;
        self
    }
    /// Sets the browser-side panic handler for your app. This is a function
    /// that will be executed if your app panics (which should never be caused
    /// by Perseus unless something is seriously wrong, it's much more likely
    /// to come from your code, or third-party code).
    ///
    /// In the case of a panic, Perseus will automatically try to render a full
    /// popup error to explain the situation to the user before terminating,
    /// but, since it's impossible to use the plugins in the case of a
    /// panic, this function is provided as an alternative in case you want
    /// to perform other work, like sending a crash report.
    ///
    /// This function **must not** panic itself, because Perseus renders the
    /// message *after* your handler is executed. If it panics, that popup
    /// will never get to the user, leading to very poor UX. That said,
    /// don't stress about calling things like `web_sys::window().unwrap()`,
    /// because, if that fails, then trying to render a popup will
    /// *definitely* fail anyway. Perseus will attempt to write an error
    /// message to the console before this, just in case anything panics.
    ///
    /// Note that there is no access within this function to Sycamore, page
    /// state, global state, or translators. Assume that your code has
    /// completely imploded when you write this function. Anything more advanced
    /// should be left to your error views system, when it handles
    /// `ClientError::Panic`.
    ///
    /// This has no default value.
    #[allow(unused_variables)]
    #[allow(unused_mut)]
    pub fn panic_handler(mut self, val: impl Fn(&PanicInfo) + Send + Sync + 'static) -> Self {
        #[cfg(any(client, doc))]
        {
            self.panic_handler = Some(Box::new(val));
        }
        self
    }

    // Getters
    /// Gets the HTML ID of the `<div>` at which to insert Perseus.
    pub fn get_root(&self) -> Result<String, PluginError> {
        let root = self
            .plugins
            .control_actions
            .settings_actions
            .set_app_root
            .run((), self.plugins.get_plugin_data())?
            .unwrap_or_else(|| self.root.to_string());
        Ok(root)
    }
    // /// Gets the directory containing static assets to be hosted under the URL
    // /// `/.perseus/static/`.
    // // TODO Plugin action for this?
    // #[cfg(engine)]
    // pub fn get_static_dir(&self) -> String {
    //     self.static_dir.to_string()
    // }
    /// Gets the index view as a string, without generating an HTML shell (pass
    /// this into `::get_html_shell()` to do that).
    ///
    /// Note that this automatically adds `<!DOCTYPE html>` to the start of the
    /// HTML shell produced, which can only be overridden with a control plugin
    /// (though you should really never do this in Perseus, which targets
    /// HTML on the web).
    #[cfg(engine)]
    pub fn get_index_view_str(&self) -> String {
        // We have to add an HTML document type declaration, otherwise the browser could
        // think it's literally anything! (This shouldn't be a problem, but it could be
        // in 100 years...)
        format!("<!DOCTYPE html>\n{}", self.index_view)
    }
    /// Gets an HTML shell from an index view string. This is broken out so that
    /// it can be executed after the app has been built (which requires getting
    /// the translations manager, consuming `self`). As inconvenient as this
    /// is, it's necessitated, otherwise exporting would try to access the built
    /// app before it had actually been built.
    #[cfg(engine)]
    pub(crate) async fn get_html_shell(
        index_view_str: String,
        root: &str,
        render_cfg: &HashMap<String, String>,
        plugins: &Plugins,
    ) -> Result<HtmlShell, PluginError> {
        // Construct an HTML shell
        let mut html_shell =
            HtmlShell::new(index_view_str, root, render_cfg, &get_path_prefix_server());

        // Apply the myriad plugin actions to the HTML shell (replacing the whole thing
        // first if need be)
        let shell_str = plugins
            .control_actions
            .settings_actions
            .html_shell_actions
            .set_shell
            .run((), plugins.get_plugin_data())?
            .unwrap_or(html_shell.shell);
        html_shell.shell = shell_str;
        // For convenience, we alias the HTML shell functional actions
        let hsf_actions = &plugins
            .functional_actions
            .settings_actions
            .html_shell_actions;

        // These all return `Vec<String>`, so the code is almost identical for all the
        // places for flexible interpolation
        html_shell.head_before_boundary.push(
            hsf_actions
                .add_to_head_before_boundary
                .run((), plugins.get_plugin_data())?
                .values()
                .flatten()
                .cloned()
                .collect(),
        );
        html_shell.scripts_before_boundary.push(
            hsf_actions
                .add_to_scripts_before_boundary
                .run((), plugins.get_plugin_data())?
                .values()
                .flatten()
                .cloned()
                .collect(),
        );
        html_shell.head_after_boundary.push(
            hsf_actions
                .add_to_head_after_boundary
                .run((), plugins.get_plugin_data())?
                .values()
                .flatten()
                .cloned()
                .collect(),
        );
        html_shell.scripts_after_boundary.push(
            hsf_actions
                .add_to_scripts_after_boundary
                .run((), plugins.get_plugin_data())?
                .values()
                .flatten()
                .cloned()
                .collect(),
        );
        html_shell.before_content.push(
            hsf_actions
                .add_to_before_content
                .run((), plugins.get_plugin_data())?
                .values()
                .flatten()
                .cloned()
                .collect(),
        );
        html_shell.after_content.push(
            hsf_actions
                .add_to_after_content
                .run((), plugins.get_plugin_data())?
                .values()
                .flatten()
                .cloned()
                .collect(),
        );

        Ok(html_shell)
    }
    // /// Gets the map of entities (i.e. templates and capsules combined).
    // pub fn get_entities_map(&self) -> EntityMap<G> {
    //     // This is cheap to clone
    //     self.entities.clone()
    // }
    // /// Gets the [`ErrorViews`] used in the app. This returns an `Rc`.
    // #[cfg(any(client, doc))]
    // pub fn get_error_views(&self) -> Rc<ErrorViews<G>> {
    //     self.error_views.clone()
    // }
    // /// Gets the [`ErrorViews`] used in the app. This returns an `Arc`.
    // #[cfg(engine)]
    // pub fn get_atomic_error_views(&self) -> Arc<ErrorViews<G>> {
    //     self.error_views.clone()
    // }
    // /// Gets the maximum number of pages that can be stored in the page state
    // /// store before the oldest are evicted.
    // pub fn get_pss_max_size(&self) -> usize {
    //     self.pss_max_size
    // }
    // /// Gets the [`GlobalStateCreator`]. This can't be directly modified by
    // /// plugins because of reactive type complexities.
    // #[cfg(engine)]
    // pub fn get_global_state_creator(&self) -> Arc<GlobalStateCreator> {
    //     self.global_state_creator.clone()
    // }
    /// Gets the locales information.
    pub fn get_locales(&self) -> Result<Locales, PluginError> {
        let locales = self.locales.clone();
        let locales = self
            .plugins
            .control_actions
            .settings_actions
            .set_locales
            .run(locales.clone(), self.plugins.get_plugin_data())?
            .unwrap_or(locales);
        Ok(locales)
    }
    /// Gets the server-side [`TranslationsManager`]. Like the mutable store,
    /// this can't be modified by plugins due to trait complexities.
    ///
    /// This involves evaluating the future stored for the translations manager,
    /// and so this consumes `self`.
    #[cfg(engine)]
    pub async fn get_translations_manager(self) -> T {
        match self.translations_manager {
            Tm::Dummy(tm) => tm,
            Tm::Full(tm) => tm.await,
        }
    }
    /// Gets the [`ImmutableStore`].
    #[cfg(engine)]
    pub fn get_immutable_store(&self) -> Result<ImmutableStore, PluginError> {
        let immutable_store = self.immutable_store.clone();
        let immutable_store = self
            .plugins
            .control_actions
            .settings_actions
            .set_immutable_store
            .run(immutable_store.clone(), self.plugins.get_plugin_data())?
            .unwrap_or(immutable_store);
        Ok(immutable_store)
    }
    // /// Gets the [`MutableStore`]. This can't be modified by plugins due to
    // /// trait complexities, so plugins should instead expose a function that
    // /// the user can use to manually set it.
    // #[cfg(engine)]
    // pub fn get_mutable_store(&self) -> M {
    //     self.mutable_store.clone()
    // }
    // /// Gets the plugins registered for the app.
    // #[cfg(engine)]
    // pub fn get_plugins(&self) -> Arc<Plugins> {
    //     self.plugins.clone()
    // }
    // /// Gets the plugins registered for the app.
    // #[cfg(any(client, doc))]
    // pub fn get_plugins(&self) -> Rc<Plugins> {
    //     self.plugins.clone()
    // }
    /// Gets the static aliases. This will check all provided resource paths to
    /// ensure they don't reference files outside the project directory, due to
    /// potential security risks in production (we don't want to
    /// accidentally serve an arbitrary in a production environment where a path
    /// may point to somewhere evil, like an alias to `/etc/passwd`).
    #[cfg(engine)]
    pub fn get_static_aliases(&self) -> Result<HashMap<String, String>, PluginError> {
        let mut static_aliases = self.static_aliases.clone();
        // This will return a map of plugin name to another map of static aliases that
        // that plugin produced
        let extra_static_aliases = self
            .plugins
            .functional_actions
            .settings_actions
            .add_static_aliases
            .run((), self.plugins.get_plugin_data())?;
        for (_plugin_name, aliases) in extra_static_aliases {
            let new_aliases: HashMap<String, String> = aliases
                .iter()
                .map(|(k, v)| (k.to_string(), v.to_string()))
                .collect();
            static_aliases.extend(new_aliases);
        }

        let mut scoped_static_aliases = HashMap::new();
        for (url, path) in static_aliases {
            // We need to move this from being scoped to the app to being scoped for
            // `.perseus/` TODO Make sure this works properly on Windows (seems
            // to..)
            let new_path = if path.starts_with('/') {
                // Absolute paths are a security risk and are disallowed
                // The reason for this is that they could point somewhere completely different
                // on a production server (like an alias to `/etc/passwd`)
                // Allowing these would also inevitably cause head-scratching in production,
                // it's much easier to disallow these
                panic!(
                    "it's a security risk to include absolute paths in `static_aliases` ('{}'), please make this relative to the project directory",
                    path
                );
            } else if path.starts_with("../") {
                // Anything outside this directory is a security risk as well
                panic!("it's a security risk to include paths outside the current directory in `static_aliases` ('{}')", path);
            } else {
                path.to_string()
            };

            scoped_static_aliases.insert(url, new_path);
        }

        Ok(scoped_static_aliases)
    }
    /// Takes the user-set panic handlers out and returns them as an owned
    /// tuple, allowing them to be used in an actual panic hook.
    ///
    /// # Future panics
    /// If this is called more than once, the view panic handler will panic when
    /// called.
    #[cfg(any(client, doc))]
    #[allow(clippy::type_complexity)]
    pub fn take_panic_handlers(
        &mut self,
    ) -> (
        Option<Box<dyn Fn(&PanicInfo) + Send + Sync + 'static>>,
        Arc<
            dyn Fn(Scope, ClientError, ErrorContext, ErrorPosition) -> (View<SsrNode>, View<G>)
                + Send
                + Sync,
        >,
    ) {
        let panic_handler_view = std::mem::replace(
            &mut self.panic_handler_view,
            Arc::new(|_, _, _, _| unreachable!()),
        );
        let general_panic_handler = self.panic_handler.take();

        (general_panic_handler, panic_handler_view)
    }
}

/// The component that represents the entrypoint at which Perseus will inject
/// itself. You can use this with the `.index_view()` method of
/// [`PerseusAppBase`] to avoid having to create the entrypoint `<div>`
/// manually.
#[component]
#[allow(non_snake_case)]
pub fn PerseusRoot<G: Html>(cx: Scope) -> View<G> {
    view! { cx,
        // Since we render the index view with no hydration IDs, this conforms
        // to the expectations of the HTML shell
        div(id = "root")
    }
}

use crate::i18n::FsTranslationsManager;
use crate::stores::FsMutableStore;

/// An alias for the usual kind of Perseus app, which uses the filesystem-based
/// mutable store and translations manager. See [`PerseusAppBase`] for details.
pub type PerseusApp<G> = PerseusAppBase<G, FsMutableStore, FsTranslationsManager>;
/// An alias for a Perseus app that uses a custom mutable store type. See
/// [`PerseusAppBase`] for details.
pub type PerseusAppWithMutableStore<G, M> = PerseusAppBase<G, M, FsTranslationsManager>;
/// An alias for a Perseus app that uses a custom translations manager type. See
/// [`PerseusAppBase`] for details.
pub type PerseusAppWithTranslationsManager<G, T> = PerseusAppBase<G, FsMutableStore, T>;
/// An alias for a fully customizable Perseus app that can accept a custom
/// mutable store and a custom translations manager. Alternatively, you could
/// just use [`PerseusAppBase`] directly.
pub type PerseusAppWithMutableStoreAndTranslationsManager<G, M, T> = PerseusAppBase<G, M, T>;