/**
 * Sprint Planner — Requirement Decomposer (RFC-0074)
 */

import type { Requirement, Task, StoryPoint } from "./types.js";

let taskCounter = 0;

/**
 * Decompose a requirement into tasks
 */
export function decomposeRequirement(
	req: Requirement,
	options?: { defaultEstimate?: StoryPoint },
): Task[] {
	const tasks: Task[] = [];
	const estimate = req.estimate ?? options?.defaultEstimate ?? 3;

	tasks.push(createTask(req, "Implementation", "todo", estimate));
	tasks.push(
		createTask(req, "Tests", "todo", Math.min(estimate, 5) as StoryPoint),
	);
	tasks.push(createTask(req, "Documentation", "todo", 1 as StoryPoint));

	for (const ac of req.acceptanceCriteria) {
		tasks.push(createTask(req, `AC: ${ac}`, "todo", 2 as StoryPoint));
	}

	return tasks;
}

function createTask(
	req: Requirement,
	title: string,
	status: Task["status"],
	estimate: StoryPoint,
): Task {
	return {
		id: `task-${++taskCounter}-${Date.now()}`,
		requirementId: req.id,
		title: `${req.title} — ${title}`,
		description: req.description,
		status,
		estimate,
		labels: req.labels,
	};
}

export function assignEstimate(complexity: number): StoryPoint {
	const points: StoryPoint[] = [1, 2, 3, 5, 8, 13, 21];
	const idx = Math.min(Math.floor(complexity / 2), points.length - 1);
	return points[idx];
}

export function sumPoints(tasks: Task[]): number {
	return tasks.reduce((sum, t) => sum + (t.estimate ?? 0), 0);
}