/**
 * InMemoryTasksClient — deterministic in-memory TasksClient for local dev.
 *
 * Holds tasks in memory partitioned by `sub` so a user only ever sees and
 * mutates their own tasks (mirroring the real ABAC LeadingKeys boundary).
 * Seeded with a couple of FAKE tasks. No AWS, no network.
 *
 * This is for build-plan §4 "in-memory dev clients (tools return real data
 * locally)".
 */

import type {
  CompleteTaskInput,
  CreateTaskInput,
  DeleteTaskInput,
  ListTasksInput,
  Task,
  TasksClient,
} from './client.js';

function seedTasks(): Map<string, Task[]> {
  return new Map<string, Task[]>([
    [
      'lauren@seahavenind.com',
      [
        {
          taskId: 'task-0001',
          sub: 'lauren@seahavenind.com',
          title: 'Order replacement dock breakers',
          description: 'Confirm 30A marine-grade rating before ordering.',
          completed: false,
          createdAt: '2026-06-20T08:00:00Z',
        },
        {
          taskId: 'task-0002',
          sub: 'lauren@seahavenind.com',
          title: 'Send insurance cert to new vendor',
          completed: true,
          createdAt: '2026-06-18T09:30:00Z',
          completedAt: '2026-06-19T10:15:00Z',
        },
      ],
    ],
    [
      'adam@seahavenind.com',
      [
        {
          taskId: 'task-0003',
          sub: 'adam@seahavenind.com',
          title: 'Review Q2 vendor balances in QBO',
          completed: false,
          createdAt: '2026-06-22T13:00:00Z',
        },
      ],
    ],
  ]);
}

/** In-memory TasksClient partitioned by sub. */
export class InMemoryTasksClient implements TasksClient {
  private readonly tasksBySub: Map<string, Task[]>;
  private counter = 1000;

  constructor() {
    this.tasksBySub = seedTasks();
  }

  async createTask(input: CreateTaskInput): Promise<Task> {
    const task: Task = {
      taskId: `task-${(++this.counter).toString().padStart(4, '0')}`,
      sub: input.sub,
      title: input.title,
      completed: false,
      createdAt: new Date().toISOString(),
    };
    if (input.description !== undefined) {
      task.description = input.description;
    }
    const list = this.tasksBySub.get(input.sub) ?? [];
    list.push(task);
    this.tasksBySub.set(input.sub, list);
    return task;
  }

  async listTasks(input: ListTasksInput): Promise<Task[]> {
    const list = this.tasksBySub.get(input.sub) ?? [];
    if (input.includeCompleted === true) {
      return [...list];
    }
    return list.filter((t) => !t.completed);
  }

  async completeTask(input: CompleteTaskInput): Promise<Task> {
    const list = this.tasksBySub.get(input.sub) ?? [];
    const task = list.find((t) => t.taskId === input.taskId);
    if (!task) {
      throw new Error(`Task ${input.taskId} not found for user ${input.sub}`);
    }
    task.completed = true;
    task.completedAt = new Date().toISOString();
    return task;
  }

  async deleteTask(input: DeleteTaskInput): Promise<void> {
    const list = this.tasksBySub.get(input.sub) ?? [];
    const idx = list.findIndex((t) => t.taskId === input.taskId);
    if (idx !== -1) {
      list.splice(idx, 1);
    }
  }
}