browser_use/dom/history_tree_processor/service.py

import hashlib
from typing import Optional

from browser_use.dom.history_tree_processor.view import DOMHistoryElement, HashedDomElement
from browser_use.dom.views import DOMElementNode


class HistoryTreeProcessor:
	""" "
	Operations on the DOM elements

	@dev be careful - text nodes can change even if elements stay the same
	"""

	@staticmethod
	def convert_dom_element_to_history_element(dom_element: DOMElementNode) -> DOMHistoryElement:
		from browser_use.browser.context import BrowserContext

		parent_branch_path = HistoryTreeProcessor._get_parent_branch_path(dom_element)
		css_selector = BrowserContext._enhanced_css_selector_for_element(dom_element)
		return DOMHistoryElement(
			dom_element.tag_name,
			dom_element.xpath,
			dom_element.highlight_index,
			parent_branch_path,
			dom_element.attributes,
			dom_element.shadow_root,
			css_selector=css_selector,
			page_coordinates=dom_element.page_coordinates,
			viewport_coordinates=dom_element.viewport_coordinates,
			viewport_info=dom_element.viewport_info,
		)

	@staticmethod
	def find_history_element_in_tree(dom_history_element: DOMHistoryElement, tree: DOMElementNode) -> Optional[DOMElementNode]:
		hashed_dom_history_element = HistoryTreeProcessor._hash_dom_history_element(dom_history_element)

		def process_node(node: DOMElementNode):
			if node.highlight_index is not None:
				hashed_node = HistoryTreeProcessor._hash_dom_element(node)
				if hashed_node == hashed_dom_history_element:
					return node
			for child in node.children:
				if isinstance(child, DOMElementNode):
					result = process_node(child)
					if result is not None:
						return result
			return None

		return process_node(tree)

	@staticmethod
	def compare_history_element_and_dom_element(dom_history_element: DOMHistoryElement, dom_element: DOMElementNode) -> bool:
		hashed_dom_history_element = HistoryTreeProcessor._hash_dom_history_element(dom_history_element)
		hashed_dom_element = HistoryTreeProcessor._hash_dom_element(dom_element)

		return hashed_dom_history_element == hashed_dom_element

	@staticmethod
	def _hash_dom_history_element(dom_history_element: DOMHistoryElement) -> HashedDomElement:
		branch_path_hash = HistoryTreeProcessor._parent_branch_path_hash(dom_history_element.entire_parent_branch_path)
		attributes_hash = HistoryTreeProcessor._attributes_hash(dom_history_element.attributes)
		xpath_hash = HistoryTreeProcessor._xpath_hash(dom_history_element.xpath)

		return HashedDomElement(branch_path_hash, attributes_hash, xpath_hash)

	@staticmethod
	def _hash_dom_element(dom_element: DOMElementNode) -> HashedDomElement:
		parent_branch_path = HistoryTreeProcessor._get_parent_branch_path(dom_element)
		branch_path_hash = HistoryTreeProcessor._parent_branch_path_hash(parent_branch_path)
		attributes_hash = HistoryTreeProcessor._attributes_hash(dom_element.attributes)
		xpath_hash = HistoryTreeProcessor._xpath_hash(dom_element.xpath)
		# text_hash = DomTreeProcessor._text_hash(dom_element)

		return HashedDomElement(branch_path_hash, attributes_hash, xpath_hash)

	@staticmethod
	def _get_parent_branch_path(dom_element: DOMElementNode) -> list[str]:
		parents: list[DOMElementNode] = []
		current_element: DOMElementNode = dom_element
		while current_element.parent is not None:
			parents.append(current_element)
			current_element = current_element.parent

		parents.reverse()

		return [parent.tag_name for parent in parents]

	@staticmethod
	def _parent_branch_path_hash(parent_branch_path: list[str]) -> str:
		parent_branch_path_string = '/'.join(parent_branch_path)
		return hashlib.sha256(parent_branch_path_string.encode()).hexdigest()

	@staticmethod
	def _attributes_hash(attributes: dict[str, str]) -> str:
		attributes_string = ''.join(f'{key}={value}' for key, value in attributes.items())
		return hashlib.sha256(attributes_string.encode()).hexdigest()

	@staticmethod
	def _xpath_hash(xpath: str) -> str:
		return hashlib.sha256(xpath.encode()).hexdigest()

	@staticmethod
	def _text_hash(dom_element: DOMElementNode) -> str:
		""" """
		text_string = dom_element.get_all_text_till_next_clickable_element()
		return hashlib.sha256(text_string.encode()).hexdigest()