{
  "$schema": "https://ui.shadcn.com/schema/registry-item.json",
  "name": "edge-geometry",
  "title": "Edge Geometry",
  "description": "Pure geometry helpers that pick the best connection sides between two node rectangles.",
  "dependencies": ["@xyflow/react"],
  "files": [
    {
      "path": "src/registry/thornberry/lib/edge-geometry.ts",
      "content": "import { Position } from \"@xyflow/react\";\n\n/** Smooth step path offset for routed edges */\nexport const EDGE_OFFSET = 20;\n\n/** Penalty applied when a side pair aligns with the node layout direction */\nconst DIRECTION_BONUS = 50;\n\n/** A node rectangle expressed as top-left corner plus size */\nexport interface NodeRect {\n  x: number;\n  y: number;\n  width: number;\n  height: number;\n}\n\ninterface Point {\n  x: number;\n  y: number;\n}\n\n/** Center point of each side of a node rectangle */\nfunction getNodeSideCenters(rect: NodeRect) {\n  return {\n    top: { x: rect.x + rect.width / 2, y: rect.y },\n    bottom: { x: rect.x + rect.width / 2, y: rect.y + rect.height },\n    left: { x: rect.x, y: rect.y + rect.height / 2 },\n    right: { x: rect.x + rect.width, y: rect.y + rect.height / 2 },\n  };\n}\n\n/** Euclidean distance between two points */\nfunction distance(p1: Point, p2: Point): number {\n  return Math.sqrt((p2.x - p1.x) ** 2 + (p2.y - p1.y) ** 2);\n}\n\n/** A connection point pair with full geometry */\ninterface ConnectionPoints {\n  sourceX: number;\n  sourceY: number;\n  targetX: number;\n  targetY: number;\n  sourcePosition: Position;\n  targetPosition: Position;\n}\n\n/**\n * Determine the best connection point coordinates between two nodes.\n *\n * Scores the four cardinal side pairs (Bottom->Top, Top->Bottom,\n * Right->Left, Left->Right) by distance, with a bonus when the pair\n * aligns with the relative layout direction of the two nodes, and\n * returns the lowest-scoring pair's coordinates.\n */\nexport function getBestConnectionPoints(\n  sourceRect: NodeRect,\n  targetRect: NodeRect,\n): ConnectionPoints {\n  const sourceSides = getNodeSideCenters(sourceRect);\n  const targetSides = getNodeSideCenters(targetRect);\n\n  type PositionPair = {\n    sourcePos: Position;\n    targetPos: Position;\n    source: Point;\n    target: Point;\n  };\n  // a fixed 4-tuple so positionPairs[0] is provably defined without a non-null assertion\n  const positionPairs: [\n    PositionPair,\n    PositionPair,\n    PositionPair,\n    PositionPair,\n  ] = [\n    {\n      sourcePos: Position.Bottom,\n      targetPos: Position.Top,\n      source: sourceSides.bottom,\n      target: targetSides.top,\n    },\n    {\n      sourcePos: Position.Top,\n      targetPos: Position.Bottom,\n      source: sourceSides.top,\n      target: targetSides.bottom,\n    },\n    {\n      sourcePos: Position.Right,\n      targetPos: Position.Left,\n      source: sourceSides.right,\n      target: targetSides.left,\n    },\n    {\n      sourcePos: Position.Left,\n      targetPos: Position.Right,\n      source: sourceSides.left,\n      target: targetSides.right,\n    },\n  ];\n\n  let bestPair = positionPairs[0];\n  let bestScore = Number.POSITIVE_INFINITY;\n\n  for (const pair of positionPairs) {\n    const dist = distance(pair.source, pair.target);\n    let penalty = 0;\n\n    if (\n      pair.sourcePos === Position.Bottom &&\n      pair.targetPos === Position.Top &&\n      targetRect.y > sourceRect.y + sourceRect.height\n    ) {\n      penalty -= DIRECTION_BONUS;\n    }\n    if (\n      pair.sourcePos === Position.Top &&\n      pair.targetPos === Position.Bottom &&\n      targetRect.y + targetRect.height < sourceRect.y\n    ) {\n      penalty -= DIRECTION_BONUS;\n    }\n    if (\n      pair.sourcePos === Position.Right &&\n      pair.targetPos === Position.Left &&\n      targetRect.x > sourceRect.x + sourceRect.width\n    ) {\n      penalty -= DIRECTION_BONUS;\n    }\n    if (\n      pair.sourcePos === Position.Left &&\n      pair.targetPos === Position.Right &&\n      targetRect.x + targetRect.width < sourceRect.x\n    ) {\n      penalty -= DIRECTION_BONUS;\n    }\n\n    const score = dist + penalty;\n    if (score < bestScore) {\n      bestScore = score;\n      bestPair = pair;\n    }\n  }\n\n  return {\n    sourceX: bestPair.source.x,\n    sourceY: bestPair.source.y,\n    targetX: bestPair.target.x,\n    targetY: bestPair.target.y,\n    sourcePosition: bestPair.sourcePos,\n    targetPosition: bestPair.targetPos,\n  };\n}\n\n/**\n * Choose which sides of the source and target nodes an edge should\n * connect to, based purely on their geometry.\n */\nexport function chooseConnectionSides(\n  source: NodeRect,\n  target: NodeRect,\n): { sourcePosition: Position; targetPosition: Position } {\n  const { sourcePosition, targetPosition } = getBestConnectionPoints(\n    source,\n    target,\n  );\n  return { sourcePosition, targetPosition };\n}\n",
      "type": "registry:lib"
    }
  ],
  "type": "registry:lib"
}