import { v } from "convex/values";
import { query, mutation } from "./_generated/server";

// Get user's collection (alias for backwards compat)
export const getByUser = query({
  args: { userId: v.id("users") },
  handler: async (ctx, { userId }) => {
    const entries = await ctx.db
      .query("collections")
      .withIndex("by_user", (q) => q.eq("userId", userId))
      .collect();

    // Enrich with card data
    const enriched = await Promise.all(
      entries.map(async (entry) => {
        const card = await ctx.db.get(entry.cardId);
        return {
          ...entry,
          card,
        };
      })
    );

    return enriched.filter((e) => e.card !== null);
  },
});

// Get user's collection
export const getMyCollection = query({
  args: { userId: v.id("users") },
  handler: async (ctx, { userId }) => {
    const entries = await ctx.db
      .query("collections")
      .withIndex("by_user", (q) => q.eq("userId", userId))
      .collect();

    // Enrich with card data
    const enriched = await Promise.all(
      entries.map(async (entry) => {
        const card = await ctx.db.get(entry.cardId);
        return {
          ...entry,
          card,
        };
      })
    );

    return enriched.filter((e) => e.card !== null);
  },
});

// Get collection stats
export const getStats = query({
  args: { userId: v.id("users") },
  handler: async (ctx, { userId }) => {
    const entries = await ctx.db
      .query("collections")
      .withIndex("by_user", (q) => q.eq("userId", userId))
      .collect();

    const totalCards = entries.reduce((sum, e) => sum + e.quantity, 0);
    const uniqueCards = entries.length;
    const foilCount = entries.filter((e) => e.isFoil).length;

    return {
      totalCards,
      uniqueCards,
      foilCount,
    };
  },
});

// Add card to collection
export const addCard = mutation({
  args: {
    userId: v.id("users"),
    cardId: v.id("cards"),
    quantity: v.number(),
    isFoil: v.boolean(),
  },
  handler: async (ctx, { userId, cardId, quantity, isFoil }) => {
    // Check if entry already exists
    const existing = await ctx.db
      .query("collections")
      .withIndex("by_user_card", (q) =>
        q.eq("userId", userId).eq("cardId", cardId).eq("isFoil", isFoil)
      )
      .first();

    if (existing) {
      // Update quantity
      await ctx.db.patch(existing._id, {
        quantity: existing.quantity + quantity,
      });
      return existing._id;
    }

    // Create new entry
    return await ctx.db.insert("collections", {
      userId,
      cardId,
      quantity,
      isFoil,
      addedAt: Date.now(),
    });
  },
});

// Alias for addCard
export const add = addCard;

// Update card quantity
export const updateQuantity = mutation({
  args: {
    entryId: v.id("collections"),
    quantity: v.number(),
  },
  handler: async (ctx, { entryId, quantity }) => {
    if (quantity <= 0) {
      await ctx.db.delete(entryId);
      return null;
    }
    await ctx.db.patch(entryId, { quantity });
    return entryId;
  },
});

// Remove card from collection
export const removeCard = mutation({
  args: { entryId: v.id("collections") },
  handler: async (ctx, { entryId }) => {
    await ctx.db.delete(entryId);
  },
});

// Alias for removeCard
export const remove = removeCard;

// Decrease quantity by 1
export const decrementQuantity = mutation({
  args: { entryId: v.id("collections") },
  handler: async (ctx, { entryId }) => {
    const entry = await ctx.db.get(entryId);
    if (!entry) return null;

    if (entry.quantity <= 1) {
      await ctx.db.delete(entryId);
      return null;
    }

    await ctx.db.patch(entryId, { quantity: entry.quantity - 1 });
    return entryId;
  },
});

// Increase quantity by 1
export const incrementQuantity = mutation({
  args: { entryId: v.id("collections") },
  handler: async (ctx, { entryId }) => {
    const entry = await ctx.db.get(entryId);
    if (!entry) return null;

    await ctx.db.patch(entryId, { quantity: entry.quantity + 1 });
    return entryId;
  },
});