//go:build js && wasm

package ultraviolet

import (
	"syscall/js"
)

func WebWindow() js.Value {
	return js.Global().Get("window")
}

func WebDocument() js.Value {
	return js.Global().Get("document")
}

func WebContent() js.Value {
	return WebDocument().
		Call(
			"getElementById",
			"content",
		)
}

func WebBuildDiv(oldNode js.Value, parent Component, view View, text string, html string, handlers AbstractHandlers) js.Value {
	return WebBuildDivInternal(
		oldNode,
		parent.(JS).Node(),
		view,
		text,
		html,
		handlers,
	)
}

func WebBuildDivInternal(oldNode js.Value, parent js.Value, view View, text string, html string, handlers AbstractHandlers) js.Value {
	newNode := WebDocument().Call("createElement", "div")
	newNode.Call("setAttribute", "style", ViewToString(view))

	if text != "" {
		newNode.Set("innerText", text)
	}

	if html != "" {
		newNode.Set("innerHTML", html)
	}

	for key, handler := range handlers {
		switch key {
		case HANDLER_CLICK:
			newNode.Call(
				"addEventListener",
				"click",
				js.FuncOf(
					func(current js.Value, args []js.Value) interface{} {
						handler(nil)
						return nil
					},
				),
			)
		}

	}

	if parent.Call("contains", oldNode).Bool() {
		parent.Call(
			"replaceChild",
			newNode,
			oldNode,
		)
	} else {
		parent.Call(
			"appendChild",
			newNode,
		)
	}

	return newNode
}

func WebBuildImg(oldNode js.Value, parentComponent Component, view View, path string, width int) js.Value {
	parent := parentComponent.(JS).Node()

	newNode := WebDocument().Call("createElement", "img")
	newNode.Call("setAttribute", "src", path)
	newNode.Call("setAttribute", "style", ViewToString(view))
	newNode.Call("setAttribute", "width", width)

	if parent.Call("contains", oldNode).Bool() {
		parent.Call(
			"replaceChild",
			newNode,
			oldNode,
		)
	} else {
		parent.Call(
			"appendChild",
			newNode,
		)
	}

	return newNode
}

func WebBuildFrame(oldNode js.Value, parentComponent Component, view View, path string) js.Value {
	parent := parentComponent.(JS).Node()

	newNode := WebDocument().Call("createElement", "iframe")
	newNode.Call("setAttribute", "src", path)
	newNode.Call("setAttribute", "style", ViewToString(view))

	if parent.Call("contains", oldNode).Bool() {
		parent.Call(
			"replaceChild",
			newNode,
			oldNode,
		)
	} else {
		parent.Call(
			"appendChild",
			newNode,
		)
	}

	return newNode
}

func WebBuildCode(oldNode js.Value, parentComponent Component, view View, language string, content string) js.Value {
	parent := parentComponent.(JS).Node()

	codeNode := WebDocument().Call("createElement", "code")
	codeNode.Call("setAttribute", "class", "language-"+language)
	codeNode.Set("textContent", content)

	newNode := WebDocument().Call("createElement", "pre")
	newNode.Call("setAttribute", "style", ViewToString(view))
	newNode.Call(
		"appendChild",
		codeNode,
	)

	if parent.Call("contains", oldNode).Bool() {
		parent.Call(
			"replaceChild",
			newNode,
			oldNode,
		)
	} else {
		parent.Call(
			"appendChild",
			newNode,
		)
	}

	WebWindow().Call("HighlightCode")
	return newNode
}

func WebCleanChildren(node js.Value) {
	children := node.Get("children")
	for i := range children.Length() {
		node.Call("removeChild", children.Index(i))
	}
}