leptos_router 0.2.0-beta

use crate::{use_navigate, use_resolved_path, ToHref};
use leptos::*;
use std::{error::Error, rc::Rc};
use wasm_bindgen::{JsCast, UnwrapThrowExt};
use wasm_bindgen_futures::JsFuture;

type OnFormData = Rc<dyn Fn(&web_sys::FormData)>;
type OnResponse = Rc<dyn Fn(&web_sys::Response)>;

/// An HTML [`form`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form) progressively
/// enhanced to use client-side routing.
#[component]
pub fn Form<A>(
    cx: Scope,
    /// [`method`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form#attr-method)
    /// is the HTTP method to submit the form with (`get` or `post`).
    #[prop(optional)]
    method: Option<&'static str>,
    /// [`action`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form#attr-action)
    /// is the URL that processes the form submission. Takes a [String], [&str], or a reactive
    /// function that returns a [String].
    action: A,
    /// [`enctype`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form#attr-enctype)
    /// is the MIME type of the form submission if `method` is `post`.
    #[prop(optional)]
    enctype: Option<String>,
    /// A signal that will be incremented whenever the form is submitted with `post`. This can useful
    /// for reactively updating a [Resource] or another signal whenever the form has been submitted.
    #[prop(optional)]
    version: Option<RwSignal<usize>>,
    /// A signal that will be set if the form submission ends in an error.
    #[prop(optional)]
    error: Option<RwSignal<Option<Box<dyn Error>>>>,
    /// A callback will be called with the [FormData](web_sys::FormData) when the form is submitted.
    #[prop(optional)]
    on_form_data: Option<OnFormData>,
    /// Sets the `class` attribute on the underlying `<form>` tag, making it easier to style.
    #[prop(optional, into)]
    class: Option<AttributeValue>,
    /// A callback will be called with the [Response](web_sys::Response) the server sends in response
    /// to a form submission.
    #[prop(optional)]
    on_response: Option<OnResponse>,
    /// Component children; should include the HTML of the form elements.
    children: Children,
) -> impl IntoView
where
    A: ToHref + 'static,
{
    fn inner(
        cx: Scope,
        method: Option<&'static str>,
        action: Memo<Option<String>>,
        enctype: Option<String>,
        version: Option<RwSignal<usize>>,
        error: Option<RwSignal<Option<Box<dyn Error>>>>,
        on_form_data: Option<OnFormData>,
        on_response: Option<OnResponse>,
        class: Option<Attribute>,
        children: Children,
    ) -> HtmlElement<html::Form> {
        let action_version = version;
        let on_submit = move |ev: web_sys::SubmitEvent| {
            if ev.default_prevented() {
                return;
            }
            let navigate = use_navigate(cx);

            let (form, method, action, enctype) = extract_form_attributes(&ev);

            let form_data =
                web_sys::FormData::new_with_form(&form).unwrap_throw();
            if let Some(on_form_data) = on_form_data.clone() {
                on_form_data(&form_data);
            }
            let params =
                web_sys::UrlSearchParams::new_with_str_sequence_sequence(
                    &form_data,
                )
                .unwrap_throw();
            let action = use_resolved_path(cx, move || action.clone())
                .get()
                .unwrap_or_default();
            // POST
            if method == "post" {
                ev.prevent_default();

                let on_response = on_response.clone();
                spawn_local(async move {
                    let res = gloo_net::http::Request::post(&action)
                        .header("Accept", "application/json")
                        .header("Content-Type", &enctype)
                        .body(params)
                        .send()
                        .await;
                    match res {
                        Err(e) => {
                            log::error!("<Form/> error while POSTing: {e:#?}");
                            if let Some(error) = error {
                                error.set(Some(Box::new(e)));
                            }
                        }
                        Ok(resp) => {
                            if let Some(version) = action_version {
                                version.update(|n| *n += 1);
                            }
                            if let Some(error) = error {
                                error.set(None);
                            }
                            if let Some(on_response) = on_response.clone() {
                                on_response(resp.as_raw());
                            }

                            if resp.status() == 303 {
                                if let Some(redirect_url) =
                                    resp.headers().get("Location")
                                {
                                    _ = navigate(
                                        &redirect_url,
                                        Default::default(),
                                    );
                                }
                            }
                        }
                    }
                });
            }
            // otherwise, GET
            else {
                let params = params.to_string().as_string().unwrap_or_default();
                if navigate(&format!("{action}?{params}"), Default::default())
                    .is_ok()
                {
                    ev.prevent_default();
                }
            }
        };

        let method = method.unwrap_or("get");

        view! { cx,
            <form
                method=method
                action=move || action.get()
                enctype=enctype
                on:submit=on_submit
                class=class
            >
                {children(cx)}
            </form>
        }
    }

    let action = use_resolved_path(cx, move || action.to_href()());
    let class = class.map(|bx| bx.into_attribute_boxed(cx));
    inner(
        cx,
        method,
        action,
        enctype,
        version,
        error,
        on_form_data,
        on_response,
        class,
        children,
    )
}

/// Automatically turns a server [Action](leptos_server::Action) into an HTML
/// [`form`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form)
/// progressively enhanced to use client-side routing.
#[component]
pub fn ActionForm<I, O>(
    cx: Scope,
    /// The action from which to build the form. This should include a URL, which can be generated
    /// by default using [create_server_action](leptos_server::create_server_action) or added
    /// manually using [leptos_server::Action::using_server_fn].
    action: Action<I, Result<O, ServerFnError>>,
    /// Sets the `class` attribute on the underlying `<form>` tag, making it easier to style.
    #[prop(optional, into)]
    class: Option<AttributeValue>,
    /// Component children; should include the HTML of the form elements.
    children: Children,
) -> impl IntoView
where
    I: Clone + ServerFn + 'static,
    O: Clone + Serializable + 'static,
{
    let action_url = if let Some(url) = action.url() {
        url
    } else {
        debug_warn!(
            "<ActionForm/> action needs a URL. Either use \
             create_server_action() or Action::using_server_fn()."
        );
        String::new()
    };
    let version = action.version();
    let value = action.value();
    let input = action.input();

    let on_form_data = Rc::new(move |form_data: &web_sys::FormData| {
        let data = action_input_from_form_data(form_data);
        match data {
            Ok(data) => {
                input.set(Some(data));
                action.set_pending(true);
            }
            Err(e) => log::error!("{e}"),
        }
    });

    let on_response = Rc::new(move |resp: &web_sys::Response| {
        let resp = resp.clone().expect("couldn't get Response");
        spawn_local(async move {
            let body = JsFuture::from(
                resp.text().expect("couldn't get .text() from Response"),
            )
            .await;
            match body {
                Ok(json) => {
                    match O::from_json(
                        &json
                            .as_string()
                            .expect("couldn't get String from JsString"),
                    ) {
                        Ok(res) => value.set(Some(Ok(res))),
                        Err(e) => value.set(Some(Err(
                            ServerFnError::Deserialization(e.to_string()),
                        ))),
                    }
                }
                Err(e) => log::error!("{e:?}"),
            };
            input.set(None);
            action.set_pending(false);
        });
    });
    let class = class.map(|bx| bx.into_attribute_boxed(cx));
    Form(
        cx,
        FormProps::builder()
            .action(action_url)
            .version(version)
            .on_form_data(on_form_data)
            .on_response(on_response)
            .method("post")
            .class(class)
            .children(children)
            .build(),
    )
}

/// Automatically turns a server [MultiAction](leptos_server::MultiAction) into an HTML
/// [`form`](https://developer.mozilla.org/en-US/docs/Web/HTML/Element/form)
/// progressively enhanced to use client-side routing.
#[component]
pub fn MultiActionForm<I, O>(
    cx: Scope,
    /// The action from which to build the form. This should include a URL, which can be generated
    /// by default using [create_server_action](leptos_server::create_server_action) or added
    /// manually using [leptos_server::Action::using_server_fn].
    action: MultiAction<I, Result<O, ServerFnError>>,
    /// Sets the `class` attribute on the underlying `<form>` tag, making it easier to style.
    #[prop(optional, into)]
    class: Option<AttributeValue>,
    /// Component children; should include the HTML of the form elements.
    children: Children,
) -> impl IntoView
where
    I: Clone + ServerFn + 'static,
    O: Clone + Serializable + 'static,
{
    let multi_action = action;
    let action = if let Some(url) = multi_action.url() {
        url
    } else {
        debug_warn!(
            "<MultiActionForm/> action needs a URL. Either use \
             create_server_action() or Action::using_server_fn()."
        );
        String::new()
    };

    let on_submit = move |ev: web_sys::SubmitEvent| {
        if ev.default_prevented() {
            return;
        }

        let (form, _, _, _) = extract_form_attributes(&ev);

        let form_data = web_sys::FormData::new_with_form(&form).unwrap_throw();
        let data = action_input_from_form_data(&form_data);
        match data {
            Err(e) => log::error!("{e}"),
            Ok(input) => {
                ev.prevent_default();
                multi_action.dispatch(input);
            }
        }
    };

    let class = class.map(|bx| bx.into_attribute_boxed(cx));
    view! { cx,
        <form
            method="POST"
            action=action
            class=class
            on:submit=on_submit
        >
            {children(cx)}
        </form>
    }
}

fn extract_form_attributes(
    ev: &web_sys::Event,
) -> (web_sys::HtmlFormElement, String, String, String) {
    let submitter = ev.unchecked_ref::<web_sys::SubmitEvent>().submitter();
    match &submitter {
        Some(el) => {
            if let Some(form) = el.dyn_ref::<web_sys::HtmlFormElement>() {
                (
                    form.clone(),
                    form.get_attribute("method")
                        .unwrap_or_else(|| "get".to_string())
                        .to_lowercase(),
                    form.get_attribute("action")
                        .unwrap_or_default()
                        .to_lowercase(),
                    form.get_attribute("enctype")
                        .unwrap_or_else(|| {
                            "application/x-www-form-urlencoded".to_string()
                        })
                        .to_lowercase(),
                )
            } else if let Some(input) =
                el.dyn_ref::<web_sys::HtmlInputElement>()
            {
                let form = ev
                    .target()
                    .unwrap()
                    .unchecked_into::<web_sys::HtmlFormElement>();
                (
                    form.clone(),
                    input.get_attribute("method").unwrap_or_else(|| {
                        form.get_attribute("method")
                            .unwrap_or_else(|| "get".to_string())
                            .to_lowercase()
                    }),
                    input.get_attribute("action").unwrap_or_else(|| {
                        form.get_attribute("action")
                            .unwrap_or_default()
                            .to_lowercase()
                    }),
                    input.get_attribute("enctype").unwrap_or_else(|| {
                        form.get_attribute("enctype")
                            .unwrap_or_else(|| {
                                "application/x-www-form-urlencoded".to_string()
                            })
                            .to_lowercase()
                    }),
                )
            } else if let Some(button) =
                el.dyn_ref::<web_sys::HtmlButtonElement>()
            {
                let form = ev
                    .target()
                    .unwrap()
                    .unchecked_into::<web_sys::HtmlFormElement>();
                (
                    form.clone(),
                    button.get_attribute("method").unwrap_or_else(|| {
                        form.get_attribute("method")
                            .unwrap_or_else(|| "get".to_string())
                            .to_lowercase()
                    }),
                    button.get_attribute("action").unwrap_or_else(|| {
                        form.get_attribute("action")
                            .unwrap_or_default()
                            .to_lowercase()
                    }),
                    button.get_attribute("enctype").unwrap_or_else(|| {
                        form.get_attribute("enctype")
                            .unwrap_or_else(|| {
                                "application/x-www-form-urlencoded".to_string()
                            })
                            .to_lowercase()
                    }),
                )
            } else {
                leptos_dom::debug_warn!(
                    "<Form/> cannot be submitted from a tag other than \
                     <form>, <input>, or <button>"
                );
                panic!()
            }
        }
        None => match ev.target() {
            None => {
                leptos_dom::debug_warn!(
                    "<Form/> SubmitEvent fired without a target."
                );
                panic!()
            }
            Some(form) => {
                let form = form.unchecked_into::<web_sys::HtmlFormElement>();
                (
                    form.clone(),
                    form.get_attribute("method")
                        .unwrap_or_else(|| "get".to_string()),
                    form.get_attribute("action").unwrap_or_default(),
                    form.get_attribute("enctype").unwrap_or_else(|| {
                        "application/x-www-form-urlencoded".to_string()
                    }),
                )
            }
        },
    }
}

fn action_input_from_form_data<I: serde::de::DeserializeOwned>(
    form_data: &web_sys::FormData,
) -> Result<I, serde_urlencoded::de::Error> {
    let data =
        web_sys::UrlSearchParams::new_with_str_sequence_sequence(form_data)
            .unwrap_throw();
    let data = data.to_string().as_string().unwrap_or_default();
    serde_urlencoded::from_str::<I>(&data)
}