""" Pin Locator for KiCad Schematics Discovers pin locations on symbol instances, accounting for position, rotation, and mirroring. Uses S-expression parsing to extract pin data from symbol definitions. """ import logging import math import tempfile from pathlib import Path from typing import List, Tuple, Optional, Dict import sexpdata from sexpdata import Symbol from skip import Schematic logger = logging.getLogger("kicad_interface") class PinLocator: """Locate pins on symbol instances in KiCad schematics""" def __init__(self): """Initialize pin locator with empty cache""" self.pin_definition_cache = {} # Cache: "lib_id:symbol_name" -> pin_data self._schematic_cache: Dict[str, object] = {} # Cache: path -> loaded Schematic @staticmethod def parse_symbol_definition(symbol_def: list) -> Dict[str, Dict]: """ Parse a symbol definition from lib_symbols to extract pin information Args: symbol_def: S-expression list representing symbol definition Returns: Dictionary mapping pin number -> pin data: { "1": {"x": 0, "y": 3.81, "angle": 270, "length": 1.27, "name": "~", "type": "passive"}, "2": {"x": 0, "y": -3.81, "angle": 90, "length": 1.27, "name": "~", "type": "passive"} } """ pins = {} def extract_pins_recursive(sexp): """Recursively search for pin definitions""" if not isinstance(sexp, list): return # Check if this is a pin definition if len(sexp) > 0 and sexp[0] == Symbol("pin"): # Pin format: (pin type shape (at x y angle) (length len) (name "name") (number "num")) pin_data = { "x": 0, "y": 0, "angle": 0, "length": 0, "name": "", "number": "", "type": str(sexp[1]) if len(sexp) > 1 else "passive", } # Extract pin attributes for item in sexp: if isinstance(item, list) and len(item) > 0: if item[0] == Symbol("at") and len(item) >= 3: pin_data["x"] = float(item[1]) pin_data["y"] = float(item[2]) if len(item) >= 4: pin_data["angle"] = float(item[3]) elif item[0] == Symbol("length") and len(item) >= 2: pin_data["length"] = float(item[1]) elif item[0] == Symbol("name") and len(item) >= 2: pin_data["name"] = str(item[1]).strip('"') elif item[0] == Symbol("number") and len(item) >= 2: pin_data["number"] = str(item[1]).strip('"') # Store by pin number if pin_data["number"]: pins[pin_data["number"]] = pin_data # Recurse into sublists for item in sexp: if isinstance(item, list): extract_pins_recursive(item) extract_pins_recursive(symbol_def) return pins def get_symbol_pins(self, schematic_path: Path, lib_id: str) -> Dict[str, Dict]: """ Get pin definitions for a symbol from the schematic's lib_symbols section Args: schematic_path: Path to .kicad_sch file lib_id: Library identifier (e.g., "Device:R", "MCU_ST_STM32F1:STM32F103C8Tx") Returns: Dictionary mapping pin number -> pin data """ # Check cache cache_key = f"{schematic_path}:{lib_id}" if cache_key in self.pin_definition_cache: logger.debug(f"Using cached pin data for {lib_id}") return self.pin_definition_cache[cache_key] try: # Read schematic with open(schematic_path, "r", encoding="utf-8") as f: sch_content = f.read() sch_data = sexpdata.loads(sch_content) # Find lib_symbols section lib_symbols = None for item in sch_data: if ( isinstance(item, list) and len(item) > 0 and item[0] == Symbol("lib_symbols") ): lib_symbols = item break if not lib_symbols: logger.error("No lib_symbols section found in schematic") return {} # Find the specific symbol definition for item in lib_symbols[1:]: # Skip 'lib_symbols' itself if ( isinstance(item, list) and len(item) > 1 and item[0] == Symbol("symbol") ): symbol_name = str(item[1]).strip('"') if symbol_name == lib_id: # Found the symbol, parse pins pins = self.parse_symbol_definition(item) self.pin_definition_cache[cache_key] = pins logger.info(f"Extracted {len(pins)} pins from {lib_id}") return pins logger.warning(f"Symbol {lib_id} not found in lib_symbols") return {} except Exception as e: logger.error(f"Error getting symbol pins: {e}") import traceback logger.error(traceback.format_exc()) return {} @staticmethod def rotate_point(x: float, y: float, angle_degrees: float) -> Tuple[float, float]: """ Rotate a point around the origin Args: x: X coordinate y: Y coordinate angle_degrees: Rotation angle in degrees (counterclockwise) Returns: (rotated_x, rotated_y) """ if angle_degrees == 0: return (x, y) angle_rad = math.radians(angle_degrees) cos_a = math.cos(angle_rad) sin_a = math.sin(angle_rad) rotated_x = x * cos_a - y * sin_a rotated_y = x * sin_a + y * cos_a return (rotated_x, rotated_y) def get_pin_location( self, schematic_path: Path, symbol_reference: str, pin_number: str ) -> Optional[List[float]]: """ Get the absolute location of a pin on a symbol instance Args: schematic_path: Path to .kicad_sch file symbol_reference: Symbol reference designator (e.g., "R1", "U1") pin_number: Pin number/identifier (e.g., "1", "2", "GND", "VCC") Returns: [x, y] absolute coordinates of the pin, or None if not found """ try: # Load schematic with kicad-skip to get symbol instance # Use cache to avoid reloading the file for every pin lookup sch_key = str(schematic_path) if sch_key not in self._schematic_cache: self._schematic_cache[sch_key] = Schematic(sch_key) sch = self._schematic_cache[sch_key] # Find the symbol instance target_symbol = None for symbol in sch.symbol: ref = symbol.property.Reference.value if ref == symbol_reference: target_symbol = symbol break if not target_symbol: logger.error(f"Symbol {symbol_reference} not found in schematic") return None # Get symbol position and rotation symbol_at = target_symbol.at.value symbol_x = float(symbol_at[0]) symbol_y = float(symbol_at[1]) symbol_rotation = float(symbol_at[2]) if len(symbol_at) > 2 else 0.0 # Get symbol lib_id lib_id = ( target_symbol.lib_id.value if hasattr(target_symbol, "lib_id") else None ) if not lib_id: logger.error(f"Symbol {symbol_reference} has no lib_id") return None logger.debug( f"Symbol {symbol_reference}: pos=({symbol_x}, {symbol_y}), rot={symbol_rotation}, lib_id={lib_id}" ) # Get pin definitions for this symbol pins = self.get_symbol_pins(schematic_path, lib_id) if not pins: logger.error(f"No pin definitions found for {lib_id}") return None # Find the requested pin if pin_number not in pins: logger.error( f"Pin {pin_number} not found on {symbol_reference}. Available pins: {list(pins.keys())}" ) return None pin_data = pins[pin_number] # Get pin position relative to symbol origin pin_rel_x = pin_data["x"] pin_rel_y = pin_data["y"] logger.debug( f"Pin {pin_number} relative position: ({pin_rel_x}, {pin_rel_y})" ) # Apply symbol rotation to pin position if symbol_rotation != 0: pin_rel_x, pin_rel_y = self.rotate_point( pin_rel_x, pin_rel_y, symbol_rotation ) logger.debug( f"After rotation {symbol_rotation}°: ({pin_rel_x}, {pin_rel_y})" ) # Calculate absolute position abs_x = symbol_x + pin_rel_x abs_y = symbol_y + pin_rel_y logger.info( f"Pin {symbol_reference}/{pin_number} located at ({abs_x}, {abs_y})" ) return [abs_x, abs_y] except Exception as e: logger.error(f"Error getting pin location: {e}") import traceback logger.error(traceback.format_exc()) return None def get_all_symbol_pins( self, schematic_path: Path, symbol_reference: str ) -> Dict[str, List[float]]: """ Get locations of all pins on a symbol instance Args: schematic_path: Path to .kicad_sch file symbol_reference: Symbol reference designator (e.g., "R1", "U1") Returns: Dictionary mapping pin number -> [x, y] coordinates """ try: # Load schematic (use cache) sch_key = str(schematic_path) if sch_key not in self._schematic_cache: self._schematic_cache[sch_key] = Schematic(sch_key) sch = self._schematic_cache[sch_key] # Find symbol target_symbol = None for symbol in sch.symbol: if symbol.property.Reference.value == symbol_reference: target_symbol = symbol break if not target_symbol: logger.error(f"Symbol {symbol_reference} not found") return {} # Get lib_id lib_id = ( target_symbol.lib_id.value if hasattr(target_symbol, "lib_id") else None ) if not lib_id: logger.error(f"Symbol {symbol_reference} has no lib_id") return {} # Get pin definitions pins = self.get_symbol_pins(schematic_path, lib_id) if not pins: return {} # Calculate location for each pin result = {} for pin_num in pins.keys(): location = self.get_pin_location( schematic_path, symbol_reference, pin_num ) if location: result[pin_num] = location logger.info(f"Located {len(result)} pins on {symbol_reference}") return result except Exception as e: logger.error(f"Error getting all symbol pins: {e}") return {} if __name__ == "__main__": # Test pin location discovery import sys sys.path.insert(0, "/home/chris/MCP/KiCAD-MCP-Server/python") from pathlib import Path from commands.component_schematic import ComponentManager from commands.schematic import SchematicManager import shutil print("=" * 80) print("PIN LOCATOR TEST") print("=" * 80) # Create test schematic with components (cross-platform temp directory) test_path = Path(tempfile.gettempdir()) / "test_pin_locator.kicad_sch" template_path = Path( "/home/chris/MCP/KiCAD-MCP-Server/python/templates/template_with_symbols_expanded.kicad_sch" ) shutil.copy(template_path, test_path) print(f"\n✓ Created test schematic: {test_path}") # Add some components print("\n[1/4] Adding test components...") sch = SchematicManager.load_schematic(str(test_path)) # Add resistor at (100, 100), rotation 0 r1_def = { "type": "R", "reference": "R1", "value": "10k", "x": 100, "y": 100, "rotation": 0, } ComponentManager.add_component(sch, r1_def, test_path) # Add capacitor at (150, 100), rotation 90 c1_def = { "type": "C", "reference": "C1", "value": "100nF", "x": 150, "y": 100, "rotation": 90, } ComponentManager.add_component(sch, c1_def, test_path) SchematicManager.save_schematic(sch, str(test_path)) print(" ✓ Added R1 and C1") # Test pin locator print("\n[2/4] Testing pin location discovery...") locator = PinLocator() # Find R1 pins r1_pin1 = locator.get_pin_location(test_path, "R1", "1") r1_pin2 = locator.get_pin_location(test_path, "R1", "2") print(f" R1 pin 1: {r1_pin1}") print(f" R1 pin 2: {r1_pin2}") # Find C1 pins (rotated 90 degrees) c1_pin1 = locator.get_pin_location(test_path, "C1", "1") c1_pin2 = locator.get_pin_location(test_path, "C1", "2") print(f" C1 pin 1: {c1_pin1}") print(f" C1 pin 2: {c1_pin2}") # Test get all pins print("\n[3/4] Testing get all pins...") r1_all_pins = locator.get_all_symbol_pins(test_path, "R1") print(f" R1 all pins: {r1_all_pins}") c1_all_pins = locator.get_all_symbol_pins(test_path, "C1") print(f" C1 all pins: {c1_all_pins}") # Verify results print("\n[4/4] Verification...") success = True if not r1_pin1 or not r1_pin2: print(" ✗ Failed to locate R1 pins") success = False else: print(" ✓ R1 pins located") if not c1_pin1 or not c1_pin2: print(" ✗ Failed to locate C1 pins") success = False else: print(" ✓ C1 pins located") # Check rotation (C1 pins should be rotated 90 degrees from R1) if r1_pin1 and c1_pin1: # R1 is not rotated, pins should be at y offset from symbol center # C1 is rotated 90°, pins should be at x offset from symbol center print(f"\n Pin offset analysis:") print(f" R1 (0°): pin 1 y-offset = {r1_pin1[1] - 100}") print(f" C1 (90°): pin 1 x-offset = {c1_pin1[0] - 150}") print("\n" + "=" * 80) if success: print("✅ PIN LOCATOR TEST PASSED!") else: print("❌ PIN LOCATOR TEST FAILED!") print("=" * 80) print(f"\nTest schematic saved: {test_path}")