import { ObjectId } from "mongodb";
import { z } from "zod";
import { getDb } from "@/lib/db";

export const strengthSetSchema = z.object({
  order: z.number().int().positive(),
  weightKg: z.number().positive().optional(),
  reps: z.number().int().positive().optional(),
});

export const strengthExerciseSchema = z.object({
  name: z.string().min(1),
  notes: z.string().optional(),
  sets: z.array(strengthSetSchema),
});

export const strengthWorkoutSchema = z.object({
  date: z.date(),
  name: z.string().min(1),
  notes: z.string().optional(),
  exercises: z.array(strengthExerciseSchema),
  sourceUrl: z.string().optional(),
  sourceKey: z.string().min(1),
});

export type StrengthSet = z.infer<typeof strengthSetSchema>;
export type StrengthExercise = z.infer<typeof strengthExerciseSchema>;
export type StrengthWorkoutInput = z.infer<typeof strengthWorkoutSchema>;

export type StrengthWorkout = StrengthWorkoutInput & {
  _id: ObjectId;
  userId: string;
  createdAt: Date;
};

const COLLECTION = "strength_workouts";

async function getCollection() {
  const db = await getDb();
  const collection = db.collection<StrengthWorkout>(COLLECTION);
  await collection.createIndex({ userId: 1, sourceKey: 1 }, { unique: true });
  return collection;
}

export async function upsertStrengthWorkout(
  userId: string,
  workout: StrengthWorkoutInput
): Promise<void> {
  const collection = await getCollection();
  await collection.updateOne(
    { userId, sourceKey: workout.sourceKey },
    {
      $set: { ...workout, userId },
      $setOnInsert: { createdAt: new Date() },
    },
    { upsert: true }
  );
}

export async function listStrengthWorkouts(userId: string): Promise<StrengthWorkout[]> {
  const collection = await getCollection();
  return collection.find({ userId }).sort({ date: -1 }).toArray();
}

export async function getStrengthWorkout(
  userId: string,
  id: string
): Promise<StrengthWorkout | null> {
  const collection = await getCollection();
  return collection.findOne({ _id: new ObjectId(id), userId });
}