Bring back pyweb as it was (#2105)

pyscript.core/src/stdlib/pyweb/pydom.py

@@ -0,0 +1,569 @@
+import inspect
+
+try:
+    from typing import Any
+except ImportError:
+    Any = "Any"
+
+try:
+    import warnings
+except ImportError:
+    # TODO: For now it probably means we are in MicroPython. We should figure
+    # out the "right" way to handle this. For now we just ignore the warning
+    # and logging to console
+    class warnings:
+        @staticmethod
+        def warn(*args, **kwargs):
+            print("WARNING: ", *args, **kwargs)
+
+
+try:
+    from functools import cached_property
+except ImportError:
+    # TODO: same comment about micropython as above
+    cached_property = property
+
+try:
+    from pyodide.ffi import JsProxy
+except ImportError:
+    # TODO: same comment about micropython as above
+    def JsProxy(obj):
+        return obj
+
+
+from pyscript import display, document, window
+
+alert = window.alert
+
+
+class JSProperty:
+    """JS property descriptor that directly maps to the property with the same
+    name in the underlying JS component."""
+
+    def __init__(self, name: str, allow_nones: bool = False):
+        self.name = name
+        self.allow_nones = allow_nones
+
+    def __get__(self, obj, objtype=None):
+        return getattr(obj._js, self.name)
+
+    def __set__(self, obj, value):
+        if not self.allow_nones and value is None:
+            return
+        setattr(obj._js, self.name, value)
+
+
+class BaseElement:
+    def __init__(self, js_element):
+        self._js = js_element
+        self._parent = None
+        self.style = StyleProxy(self)
+        self._proxies = {}
+
+    def __eq__(self, obj):
+        """Check if the element is the same as the other element by comparing
+        the underlying JS element"""
+        return isinstance(obj, BaseElement) and obj._js == self._js
+
+    @property
+    def parent(self):
+        if self._parent:
+            return self._parent
+
+        if self._js.parentElement:
+            self._parent = self.__class__(self._js.parentElement)
+
+        return self._parent
+
+    @property
+    def __class(self):
+        return self.__class__ if self.__class__ != PyDom else Element
+
+    def create(self, type_, is_child=True, classes=None, html=None, label=None):
+        js_el = document.createElement(type_)
+        element = self.__class(js_el)
+
+        if classes:
+            for class_ in classes:
+                element.add_class(class_)
+
+        if html is not None:
+            element.html = html
+
+        if label is not None:
+            element.label = label
+
+        if is_child:
+            self.append(element)
+
+        return element
+
+    def find(self, selector):
+        """Return an ElementCollection representing all the child elements that
+        match the specified selector.
+
+        Args:
+            selector (str): A string containing a selector expression
+
+        Returns:
+            ElementCollection: A collection of elements matching the selector
+        """
+        elements = self._js.querySelectorAll(selector)
+        if not elements:
+            return None
+        return ElementCollection([Element(el) for el in elements])
+
+
+class Element(BaseElement):
+    @property
+    def children(self):
+        return [self.__class__(el) for el in self._js.children]
+
+    def append(self, child):
+        # TODO: this is Pyodide specific for now!!!!!!
+        # if we get passed a JSProxy Element directly we just map it to the
+        # higher level Python element
+        if inspect.isclass(JsProxy) and isinstance(child, JsProxy):
+            return self.append(Element(child))
+
+        elif isinstance(child, Element):
+            self._js.appendChild(child._js)
+
+            return child
+
+        elif isinstance(child, ElementCollection):
+            for el in child:
+                self.append(el)
+
+    # -------- Pythonic Interface to Element -------- #
+    @property
+    def html(self):
+        return self._js.innerHTML
+
+    @html.setter
+    def html(self, value):
+        self._js.innerHTML = value
+
+    @property
+    def text(self):
+        return self._js.textContent
+
+    @text.setter
+    def text(self, value):
+        self._js.textContent = value
+
+    @property
+    def content(self):
+        # TODO: This breaks with with standard template elements. Define how to best
+        #       handle this specifica use case. Just not support for now?
+        if self._js.tagName == "TEMPLATE":
+            warnings.warn(
+                "Content attribute not supported for template elements.", stacklevel=2
+            )
+            return None
+        return self._js.innerHTML
+
+    @content.setter
+    def content(self, value):
+        # TODO: (same comment as above)
+        if self._js.tagName == "TEMPLATE":
+            warnings.warn(
+                "Content attribute not supported for template elements.", stacklevel=2
+            )
+            return
+
+        display(value, target=self.id)
+
+    @property
+    def id(self):
+        return self._js.id
+
+    @id.setter
+    def id(self, value):
+        self._js.id = value
+
+    @property
+    def options(self):
+        if "options" in self._proxies:
+            return self._proxies["options"]
+
+        if not self._js.tagName.lower() in {"select", "datalist", "optgroup"}:
+            raise AttributeError(
+                f"Element {self._js.tagName} has no options attribute."
+            )
+        self._proxies["options"] = OptionsProxy(self)
+        return self._proxies["options"]
+
+    @property
+    def value(self):
+        return self._js.value
+
+    @value.setter
+    def value(self, value):
+        # in order to avoid confusion to the user, we don't allow setting the
+        # value of elements that don't have a value attribute
+        if not hasattr(self._js, "value"):
+            raise AttributeError(
+                f"Element {self._js.tagName} has no value attribute. If you want to "
+                "force a value attribute, set it directly using the `_js.value = <value>` "
+                "javascript API attribute instead."
+            )
+        self._js.value = value
+
+    @property
+    def selected(self):
+        return self._js.selected
+
+    @selected.setter
+    def selected(self, value):
+        # in order to avoid confusion to the user, we don't allow setting the
+        # value of elements that don't have a value attribute
+        if not hasattr(self._js, "selected"):
+            raise AttributeError(
+                f"Element {self._js.tagName} has no value attribute. If you want to "
+                "force a value attribute, set it directly using the `_js.value = <value>` "
+                "javascript API attribute instead."
+            )
+        self._js.selected = value
+
+    def clone(self, new_id=None):
+        clone = Element(self._js.cloneNode(True))
+        clone.id = new_id
+
+        return clone
+
+    def remove_class(self, classname):
+        classList = self._js.classList
+        if isinstance(classname, list):
+            classList.remove(*classname)
+        else:
+            classList.remove(classname)
+        return self
+
+    def add_class(self, classname):
+        classList = self._js.classList
+        if isinstance(classname, list):
+            classList.add(*classname)
+        else:
+            self._js.classList.add(classname)
+        return self
+
+    @property
+    def classes(self):
+        classes = self._js.classList.values()
+        return [x for x in classes]
+
+    def show_me(self):
+        self._js.scrollIntoView()
+
+    def snap(
+        self,
+        to: BaseElement | str = None,
+        width: int | None = None,
+        height: int | None = None,
+    ):
+        """
+        Captures a snapshot of a video element. (Only available for video elements)
+
+        Inputs:
+
+            * to: element where to save the snapshot of the video frame to
+            * width: width of the image
+            * height: height of the image
+
+        Output:
+            (Element) canvas element where the video frame snapshot was drawn into
+        """
+        if self._js.tagName != "VIDEO":
+            raise AttributeError("Snap method is only available for video Elements")
+
+        if to is None:
+            canvas = self.create("canvas")
+            if width is None:
+                width = self._js.width
+            if height is None:
+                height = self._js.height
+            canvas._js.width = width
+            canvas._js.height = height
+
+        elif isinstance(to, Element):
+            if to._js.tagName != "CANVAS":
+                raise TypeError("Element to snap to must a canvas.")
+            canvas = to
+        elif getattr(to, "tagName", "") == "CANVAS":
+            canvas = Element(to)
+        elif isinstance(to, str):
+            canvas = pydom[to][0]
+            if canvas._js.tagName != "CANVAS":
+                raise TypeError("Element to snap to must a be canvas.")
+
+        canvas.draw(self, width, height)
+
+        return canvas
+
+    def download(self, filename: str = "snapped.png") -> None:
+        """Download the current element (only available for canvas elements) with the filename
+        provided in input.
+
+        Inputs:
+            * filename (str): name of the file being downloaded
+
+        Output:
+            None
+        """
+        if self._js.tagName != "CANVAS":
+            raise AttributeError(
+                "The download method is only available for canvas Elements"
+            )
+
+        link = self.create("a")
+        link._js.download = filename
+        link._js.href = self._js.toDataURL()
+        link._js.click()
+
+    def draw(self, what, width, height):
+        """Draw `what` on the current element  (only available for canvas elements).
+
+        Inputs:
+
+            * what (canvas image source): An element to draw into the context. The specification permits any canvas
+                image source, specifically, an HTMLImageElement, an SVGImageElement, an HTMLVideoElement,
+                an HTMLCanvasElement, an ImageBitmap, an OffscreenCanvas, or a VideoFrame.
+        """
+        if self._js.tagName != "CANVAS":
+            raise AttributeError(
+                "The draw method is only available for canvas Elements"
+            )
+
+        if isinstance(what, Element):
+            what = what._js
+
+        # https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/drawImage
+        self._js.getContext("2d").drawImage(what, 0, 0, width, height)
+
+
+class OptionsProxy:
+    """This class represents the options of a select element. It
+    allows to access to add and remove options by using the `add` and `remove` methods.
+    """
+
+    def __init__(self, element: Element) -> None:
+        self._element = element
+        if self._element._js.tagName.lower() != "select":
+            raise AttributeError(
+                f"Element {self._element._js.tagName} has no options attribute."
+            )
+
+    def add(
+        self,
+        value: Any = None,
+        html: str = None,
+        text: str = None,
+        before: Element | int = None,
+        **kws,
+    ) -> None:
+        """Add a new option to the select element"""
+        # create the option element and set the attributes
+        option = document.createElement("option")
+        if value is not None:
+            kws["value"] = value
+        if html is not None:
+            option.innerHTML = html
+        if text is not None:
+            kws["text"] = text
+
+        for key, value in kws.items():
+            option.setAttribute(key, value)
+
+        if before:
+            if isinstance(before, Element):
+                before = before._js
+
+        self._element._js.add(option, before)
+
+    def remove(self, item: int) -> None:
+        """Remove the option at the specified index"""
+        self._element._js.remove(item)
+
+    def clear(self) -> None:
+        """Remove all the options"""
+        for i in range(len(self)):
+            self.remove(0)
+
+    @property
+    def options(self):
+        """Return the list of options"""
+        return [Element(opt) for opt in self._element._js.options]
+
+    @property
+    def selected(self):
+        """Return the selected option"""
+        return self.options[self._element._js.selectedIndex]
+
+    def __iter__(self):
+        yield from self.options
+
+    def __len__(self):
+        return len(self.options)
+
+    def __repr__(self):
+        return f"{self.__class__.__name__} (length: {len(self)}) {self.options}"
+
+    def __getitem__(self, key):
+        return self.options[key]
+
+
+class StyleProxy:  # (dict):
+    def __init__(self, element: Element) -> None:
+        self._element = element
+
+    @cached_property
+    def _style(self):
+        return self._element._js.style
+
+    def __getitem__(self, key):
+        return self._style.getPropertyValue(key)
+
+    def __setitem__(self, key, value):
+        self._style.setProperty(key, value)
+
+    def remove(self, key):
+        self._style.removeProperty(key)
+
+    def set(self, **kws):
+        for k, v in kws.items():
+            self._element._js.style.setProperty(k, v)
+
+    # CSS Properties
+    # Reference: https://github.com/microsoft/TypeScript/blob/main/src/lib/dom.generated.d.ts#L3799C1-L5005C2
+    # Following prperties automatically generated from the above reference using
+    # tools/codegen_css_proxy.py
+    @property
+    def visible(self):
+        return self._element._js.style.visibility
+
+    @visible.setter
+    def visible(self, value):
+        self._element._js.style.visibility = value
+
+
+class StyleCollection:
+    def __init__(self, collection: "ElementCollection") -> None:
+        self._collection = collection
+
+    def __get__(self, obj, objtype=None):
+        return obj._get_attribute("style")
+
+    def __getitem__(self, key):
+        return self._collection._get_attribute("style")[key]
+
+    def __setitem__(self, key, value):
+        for element in self._collection._elements:
+            element.style[key] = value
+
+    def remove(self, key):
+        for element in self._collection._elements:
+            element.style.remove(key)
+
+
+class ElementCollection:
+    def __init__(self, elements: [Element]) -> None:
+        self._elements = elements
+        self.style = StyleCollection(self)
+
+    def __getitem__(self, key):
+        # If it's an integer we use it to access the elements in the collection
+        if isinstance(key, int):
+            return self._elements[key]
+        # If it's a slice we use it to support slice operations over the elements
+        # in the collection
+        elif isinstance(key, slice):
+            return ElementCollection(self._elements[key])
+
+        # If it's anything else (basically a string) we use it as a selector
+        # TODO: Write tests!
+        elements = self._element.querySelectorAll(key)
+        return ElementCollection([Element(el) for el in elements])
+
+    def __len__(self):
+        return len(self._elements)
+
+    def __eq__(self, obj):
+        """Check if the element is the same as the other element by comparing
+        the underlying JS element"""
+        return isinstance(obj, ElementCollection) and obj._elements == self._elements
+
+    def _get_attribute(self, attr, index=None):
+        if index is None:
+            return [getattr(el, attr) for el in self._elements]
+
+        # As JQuery, when getting an attr, only return it for the first element
+        return getattr(self._elements[index], attr)
+
+    def _set_attribute(self, attr, value):
+        for el in self._elements:
+            setattr(el, attr, value)
+
+    @property
+    def html(self):
+        return self._get_attribute("html")
+
+    @html.setter
+    def html(self, value):
+        self._set_attribute("html", value)
+
+    @property
+    def value(self):
+        return self._get_attribute("value")
+
+    @value.setter
+    def value(self, value):
+        self._set_attribute("value", value)
+
+    @property
+    def children(self):
+        return self._elements
+
+    def __iter__(self):
+        yield from self._elements
+
+    def __repr__(self):
+        return f"{self.__class__.__name__} (length: {len(self._elements)}) {self._elements}"
+
+
+class DomScope:
+    def __getattr__(self, __name: str):
+        element = document[f"#{__name}"]
+        if element:
+            return element[0]
+
+
+class PyDom(BaseElement):
+    # Add objects we want to expose to the DOM namespace since this class instance is being
+    # remapped as "the module" itself
+    BaseElement = BaseElement
+    Element = Element
+    ElementCollection = ElementCollection
+
+    def __init__(self):
+        # PyDom is a special case of BaseElement where we don't want to create a new JS element
+        # and it really doesn't have a need for styleproxy or parent to to call to __init__
+        # (which actually fails in MP for some reason)
+        self._js = document
+        self._parent = None
+        self._proxies = {}
+        self.ids = DomScope()
+        self.body = Element(document.body)
+        self.head = Element(document.head)
+
+    def create(self, type_, classes=None, html=None):
+        return super().create(type_, is_child=False, classes=classes, html=html)
+
+    def __getitem__(self, key):
+        elements = self._js.querySelectorAll(key)
+        if not elements:
+            return None
+        return ElementCollection([Element(el) for el in elements])
+
+
+dom = PyDom()