/**
 * Shared ReactFlow edge palette + styling, extracted verbatim from
 * `ProviderTopology.tsx` (U0). Reused by the Combo/Routing Studio (Tela B) and
 * the Compression Studio (Tela A) so all three flow graphs speak the same
 * color language: green = active, red = error, amber = last-used, muted = idle.
 */
import { STATUS_HEX } from "@/shared/constants/statusColors";

export const FLOW_EDGE_COLORS = {
  active: STATUS_HEX.success,
  error: STATUS_HEX.error,
  last: STATUS_HEX.warning,
  idle: "var(--color-border)",
} as const;

export interface FlowEdgeStyle {
  stroke: string;
  strokeWidth: number;
  opacity: number;
}

/**
 * Resolve the stroke style for an edge given its state. Precedence is
 * error > active > last-used > idle — identical to the original ProviderTopology
 * implementation (do not reorder without updating the home regression).
 */
export function edgeStyle(active: boolean, last: boolean, error: boolean): FlowEdgeStyle {
  if (error) return { stroke: FLOW_EDGE_COLORS.error, strokeWidth: 2, opacity: 0.85 };
  if (active) return { stroke: FLOW_EDGE_COLORS.active, strokeWidth: 2.5, opacity: 1 };
  if (last) return { stroke: FLOW_EDGE_COLORS.last, strokeWidth: 1.5, opacity: 0.6 };
  return { stroke: FLOW_EDGE_COLORS.idle, strokeWidth: 1, opacity: 0.2 };
}