#!/usr/bin/env python3
"""
Math Operation Node:
  - Inputs: Two input ports ("A" and "B").
  - Output: One output port ("Result").
  - Operation: A dropdown (combo menu) to select:
      Add, Subtract, Multiply, Divide, Average.
  - Displays the computed result in a read-only text box labeled "Result".
"""

from OdenGraphQt import BaseNode

class MathOperationNode(BaseNode):
    __identifier__ = 'bunny-lab.io.math_node'
    NODE_NAME = 'Math Operation'

    def __init__(self):
        super(MathOperationNode, self).__init__()

        # ----------------------------------------------------------------------
        # Initialization Section:
        #   - Create two input ports: A, B
        #   - Create one output port: Result
        #   - Add a combo box for operator selection
        #   - Add a text input for displaying the computed result
        # ----------------------------------------------------------------------
        self.add_input('A')
        self.add_input('B')
        self.add_output('Result')

        # Operator combo box (Add, Subtract, Multiply, Divide, Average)
        self.add_combo_menu('operator', 'Operator', items=[
            'Add', 'Subtract', 'Multiply', 'Divide', 'Average'
        ])

        # Text input for displaying the computed result.
        # We'll make it read-only by accessing the underlying QLineEdit.
        self.add_text_input('calc_result', 'Result', text='0')
        result_widget = self.get_widget('calc_result')  # This is a NodeLineEdit wrapper
        if result_widget:
            # Get the underlying QLineEdit
            line_edit = result_widget.get_custom_widget()
            # Make the QLineEdit read-only
            line_edit.setReadOnly(True)

        self.value = 0
        self.set_name("Math Operation")
        self.process_input()

    def process_input(self, event=None):
        """
        Compute Section:
          - For each input port (A, B), if connected, grab the 'value' from
            the upstream node; otherwise default to 0.0.
          - Convert to float, apply the selected operation from the combo box,
            update the "Result" text box, node title, and output port.
        """
        # Gather input A
        input_a = self.input(0)
        if input_a and input_a.connected_ports():
            a_raw = input_a.connected_ports()[0].node().get_property('value')
        else:
            a_raw = 0.0

        # Gather input B
        input_b = self.input(1)
        if input_b and input_b.connected_ports():
            b_raw = input_b.connected_ports()[0].node().get_property('value')
        else:
            b_raw = 0.0

        # Convert raw inputs to floats (default 0.0 on failure).
        try:
            a_val = float(a_raw)
        except (ValueError, TypeError):
            a_val = 0.0
        try:
            b_val = float(b_raw)
        except (ValueError, TypeError):
            b_val = 0.0

        # Retrieve the selected operator from the combo box.
        operator = self.get_property('operator')
        result = 0.0

        if operator == 'Add':
            result = a_val + b_val
        elif operator == 'Subtract':
            result = a_val - b_val
        elif operator == 'Multiply':
            result = a_val * b_val
        elif operator == 'Divide':
            result = a_val / b_val if b_val != 0 else 0.0
        elif operator == 'Average':
            result = (a_val + b_val) / 2.0

        self.value = result

        # Update the read-only text input and node title.
        self.set_property('calc_result', str(result))

        # Transmit the numeric result to any connected output nodes.
        output_port = self.output(0)
        if output_port and output_port.connected_ports():
            for cp in output_port.connected_ports():
                connected_node = cp.node()
                if hasattr(connected_node, 'receive_data'):
                    connected_node.receive_data(result, source_port_name='Result')

    def on_input_connected(self, input_port, output_port):
        self.process_input()

    def on_input_disconnected(self, input_port, output_port):
        self.process_input()

    def property_changed(self, property_name):
        if property_name in ['operator']:
            self.process_input()

    def receive_data(self, data, source_port_name=None):
        self.process_input()