r"""
Visitor for <maction> (action/interactive) MathML elements.

The <maction> element binds actions (like tooltips, highlighting, or toggling)
to mathematical expressions. It typically has an actiontype attribute that
specifies the kind of action.

In LaTeX conversion, maction is treated as a transparent wrapper since LaTeX
is a static typesetting system without interactive capabilities. Only the
selected child (typically the first) is converted.

Common action types:
- toggle: Toggle between alternative expressions
- statusline: Display expression in status line
- tooltip: Show tooltip on hover
- highlight: Highlight on mouseover
"""

from lxml import etree as ET
from ..core.interfaces import Visitor, Strategy
from ..utils import local_name as _local


class MactionVisitor(Visitor):
    r"""
    Handles <maction> (action/interactive) MathML elements.

    Treats maction as a transparent wrapper, converting only the selected
    child (typically the first one) since LaTeX doesn't support interactivity.

    Examples:
        Toggle action (shows first alternative):
            <maction actiontype="toggle">
                <mi>x</mi>
                <mi>y</mi>
            </maction>
            → x

        Tooltip action (shows content, ignores tooltip):
            <maction actiontype="tooltip">
                <mi>a</mi>
                <mtext>variable a</mtext>
            </maction>
            → a

        Highlight action (shows content without highlight):
            <maction actiontype="highlight">
                <mfrac><mi>a</mi><mi>b</mi></mfrac>
            </maction>
            → \frac{a}{b}

        Selection attribute (selects specific child):
            <maction actiontype="toggle" selection="2">
                <mi>x</mi>
                <mi>y</mi>
                <mi>z</mi>
            </maction>
            → y (second child, 1-indexed)

    Note:
        LaTeX has no interactive capabilities, so:
        - Only one child is rendered (the selected one)
        - Action types are ignored
        - Default: first child is selected
    """

    def __init__(self, strategy: Strategy):
        """Initialize the Maction visitor."""
        super().__init__(strategy)

    def visit(self, node: ET.Element) -> str:
        r"""
        Convert <maction> element to LaTeX (renders selected child only).

        Args:
            node: The <maction> element to convert

        Returns:
            LaTeX string with selected child converted

        Raises:
            ValueError: If node is not a <maction> element
        """
        if not self.can_handle(node):
            raise ValueError(f"MactionVisitor cannot handle element '{node.tag}'")

        # Get selection attribute (1-indexed, defaults to 1)
        selection = node.get("selection", "1")
        try:
            selection_idx = int(selection) - 1  # Convert to 0-indexed
        except ValueError:
            selection_idx = 0  # Default to first child if invalid

        # Get children
        children = list(node)
        if not children:
            return ""

        # Ensure selection is within bounds
        if selection_idx < 0 or selection_idx >= len(children):
            selection_idx = 0

        # Convert only the selected child
        return self._convert_child(children[selection_idx])

    def _convert_child(self, child: ET.Element) -> str:
        """Convert a child element to LaTeX."""
        tag = _local(child.tag)

        # Import visitors as needed to avoid circular imports
        if tag == 'mi':
            from .mi_visitor import MiVisitor
            return MiVisitor(self.strategy).visit(child)
        elif tag == 'mo':
            from .mo_visitor import MoVisitor
            return MoVisitor(self.strategy).visit(child)
        elif tag == 'mn':
            from .mn_visitor import MnVisitor
            return MnVisitor(self.strategy).visit(child)
        elif tag == 'mfrac':
            from .mfrac_visitor import MfracVisitor
            return MfracVisitor(self.strategy).visit(child)
        elif tag == 'msup':
            from .msup_visitor import MsupVisitor
            return MsupVisitor(self.strategy).visit(child)
        elif tag == 'msub':
            from .msub_visitor import MsubVisitor
            return MsubVisitor(self.strategy).visit(child)
        elif tag == 'mrow':
            from .mrow_visitor import MrowVisitor
            return MrowVisitor(self.strategy).visit(child)
        elif tag == 'msqrt':
            from .msqrt_visitor import MsqrtVisitor
            return MsqrtVisitor(self.strategy).visit(child)
        elif tag == 'mroot':
            from .mroot_visitor import MrootVisitor
            return MrootVisitor(self.strategy).visit(child)
        elif tag == 'msubsup':
            from .msubsup_visitor import MsubsupVisitor
            return MsubsupVisitor(self.strategy).visit(child)
        elif tag == 'munder':
            from .munder_visitor import MunderVisitor
            return MunderVisitor(self.strategy).visit(child)
        elif tag == 'mover':
            from .mover_visitor import MoverVisitor
            return MoverVisitor(self.strategy).visit(child)
        elif tag == 'munderover':
            from .munderover_visitor import MunderoverVisitor
            return MunderoverVisitor(self.strategy).visit(child)
        elif tag == 'mfenced':
            from .mfenced_visitor import MfencedVisitor
            return MfencedVisitor(self.strategy).visit(child)
        elif tag == 'mtable':
            from .mtable_visitor import MtableVisitor
            return MtableVisitor(self.strategy).visit(child)
        elif tag == 'mtext':
            from .mtext_visitor import MtextVisitor
            return MtextVisitor(self.strategy).visit(child)
        elif tag == 'mstyle':
            from .mstyle_visitor import MstyleVisitor
            return MstyleVisitor(self.strategy).visit(child)
        elif tag == 'mspace':
            from .mspace_visitor import MspaceVisitor
            return MspaceVisitor(self.strategy).visit(child)
        elif tag == 'menclose':
            from .menclose_visitor import MencloseVisitor
            return MencloseVisitor(self.strategy).visit(child)
        elif tag == 'mmultiscripts':
            from .mmultiscripts_visitor import MmultiscriptsVisitor
            return MmultiscriptsVisitor(self.strategy).visit(child)
        elif tag == 'maction':
            from .maction_visitor import MactionVisitor
            return MactionVisitor(self.strategy).visit(child)
        elif tag == 'merror':
            from .merror_visitor import MerrorVisitor
            return MerrorVisitor(self.strategy).visit(child)
        elif tag == 'mpadded':
            from .mpadded_visitor import MpaddedVisitor
            return MpaddedVisitor(self.strategy).visit(child)
        elif tag == 'mphantom':
            from .mphantom_visitor import MphantomVisitor
            return MphantomVisitor(self.strategy).visit(child)
        elif tag == 'ms':
            from .ms_visitor import MsVisitor
            return MsVisitor(self.strategy).visit(child)
        elif tag == 'mglyph':
            from .mglyph_visitor import MglyphVisitor
            return MglyphVisitor(self.strategy).visit(child)
        elif tag == 'maligngroup':
            from .maligngroup_visitor import MaligngroupVisitor
            return MaligngroupVisitor(self.strategy).visit(child)
        elif tag == 'malignmark':
            from .malignmark_visitor import MalignmarkVisitor
            return MalignmarkVisitor(self.strategy).visit(child)
        elif tag == 'mlabeledtr':
            from .mlabeledtr_visitor import MlabeledtrVisitor
            return MlabeledtrVisitor(self.strategy).visit(child)
        else:
            # Fallback: return text content for unknown elements
            import sys
            print(f"[WARNING] Unknown element <{tag}> in maction, using text fallback", file=sys.stderr)
            return _text_content(child)

    def can_handle(self, node: ET.Element) -> bool:
        """Check if this visitor can handle the given node."""
        return _local(node.tag) == 'maction'

    @property
    def element_name(self) -> str:
        """Get the element name this visitor handles."""
        return 'maction'

    def __repr__(self) -> str:
        """String representation for debugging."""
        return f"MactionVisitor(strategy={self.strategy.name})"