/**
 * Data type system for shape-to-shape data piping.
 *
 * Shapes declare typed input/output ports. Arrows connect ports,
 * flowing data from source outputs to target inputs with type checking.
 */

/** Supported data types for ports. */
export type DataType =
	| "string"
	| "number"
	| "boolean"
	| "image-url"
	| "video-url"
	| "text"
	| "json"
	| "trigger"
	| "any";

/** Describes a single input or output port on a shape. */
export interface PortDescriptor {
	name: string;
	type: DataType;
	direction: "input" | "output";
}

/** Type compatibility matrix: can `source` flow into `target`? */
export function isCompatible(source: DataType, target: DataType): boolean {
	if (source === target) return true;
	if (target === "any" || source === "any") return true;
	// text and string are interchangeable
	if ((source === "text" && target === "string") || (source === "string" && target === "text")) return true;
	// URLs are strings
	if ((source === "image-url" || source === "video-url") && (target === "string" || target === "text")) return true;
	// strings can be image/video URLs (user knows best)
	if ((source === "string" || source === "text") && (target === "image-url" || target === "video-url")) return true;
	return false;
}

/** Color tint per data type for arrow visualization. */
export function dataTypeColor(type: DataType): string {
	switch (type) {
		case "text":
		case "string":
			return "#3b82f6"; // blue
		case "number":
			return "#f59e0b"; // amber
		case "boolean":
			return "#8b5cf6"; // purple
		case "image-url":
			return "#10b981"; // emerald
		case "video-url":
			return "#ef4444"; // red
		case "json":
			return "#6366f1"; // indigo
		case "trigger":
			return "#f97316"; // orange
		case "any":
		default:
			return "#6b7280"; // gray
	}
}