import { describe, it, expect, beforeEach, vi } from "vitest";

// --- PocketBase mock ---------------------------------------------------------
// The mock state has to be hoisted to the top of the file because Vitest
// hoists `vi.mock` factories above all imports. The state lives in a
// `vi.hoisted` block so the factory can close over it.

const { store, pbMock, clearStore } = vi.hoisted(() => {
  type StoreMap = Map<string, Record<string, unknown>>;
  const store: Record<string, StoreMap> = {};
  let seq = 0;
  const nextId = () => `mock-${++seq}`;

  const getOrCreateMap = (name: string): StoreMap => {
    if (!store[name]) store[name] = new Map();
    return store[name];
  };

  const where = (name: string, filter: string): Record<string, unknown>[] => {
    const items = Array.from(getOrCreateMap(name).values());
    if (!filter || !filter.trim()) return items;
    const clauses = filter.split("&&").map((c) => c.trim());
    return items.filter((item) =>
      clauses.every((clause) => {
        const m = clause.match(/^(\w+)\s*=\s*"?([^"]+)"?$/);
        if (!m) return true;
        const [, field, raw] = m;
        const value = raw.replace(/^"|"$/g, "");
        if (field === "year" || field === "month") {
          return Number(item[field]) === Number(value);
        }
        return String(item[field] ?? "") === value;
      }),
    );
  };

  const pbMock = {
    collection: (name: string) => ({
      async getList(
        _page = 1,
        _perPage = 25,
        opts: { filter?: string; sort?: string } = {},
      ) {
        const items = where(name, opts.filter || "");
        if (opts.sort) {
          const sign = opts.sort.startsWith("-") ? -1 : 1;
          const field = opts.sort.replace(/^-/, "");
          items.sort((a, b) => {
            const av = a[field] as string | number | undefined;
            const bv = b[field] as string | number | undefined;
            if (av === bv) return 0;
            if (av === undefined) return 1;
            if (bv === undefined) return -1;
            return (av > bv ? 1 : -1) * sign;
          });
        }
        return { items, totalItems: items.length, page: 1, perPage: _perPage };
      },
      async getFullList() {
        return where(name, "");
      },
      async getFirstListItem(filter: string) {
        const items = where(name, filter);
        if (items.length === 0) {
          const err = new Error("not found") as Error & { status: number };
          err.status = 404;
          throw err;
        }
        return items[0];
      },
      async getOne(id: string) {
        const item = getOrCreateMap(name).get(id);
        if (!item) {
          const err = new Error("not found") as Error & { status: number };
          err.status = 404;
          throw err;
        }
        return item;
      },
      async create(data: Record<string, unknown>) {
        if (name === "order_counters") {
          const map = getOrCreateMap(name);
          for (const item of map.values()) {
            if (item.year === data.year && item.month === data.month) {
              const err = new Error("unique constraint") as Error & { status: number };
              err.status = 409;
              throw err;
            }
          }
        }
        const item = {
          id: nextId(),
          created: new Date().toISOString(),
          updated: new Date().toISOString(),
          ...data,
        };
        getOrCreateMap(name).set(item.id, item);
        return item;
      },
      async update(id: string, data: Record<string, unknown>) {
        const map = getOrCreateMap(name);
        const existing = map.get(id);
        if (!existing) {
          const err = new Error("not found") as Error & { status: number };
          err.status = 404;
          throw err;
        }
        for (const [key, value] of Object.entries(data)) {
          if (key.endsWith("+")) {
            const real = key.slice(0, -1);
            existing[real] = Number(existing[real] ?? 0) + Number(value);
          } else {
            existing[key] = value;
          }
        }
        existing.updated = new Date().toISOString();
        return { ...existing };
      },
    }),
  };

  const clearStore = () => {
    for (const key of Object.keys(store)) delete store[key];
    seq = 0;
  };

  return { store, pbMock, clearStore };
});

vi.mock("pocketbase", () => {
  return {
    default: vi.fn().mockImplementation(() => pbMock),
  };
});

vi.mock("./pocketbase-admin", () => ({
  getAdminPocketBase: vi.fn().mockResolvedValue(pbMock),
}));

import {
  createOrderFromQuote,
  getOrderItemsCollectionName,
  listCollectionPool,
} from "./orders-service";

beforeEach(() => {
  clearStore();
});

// --- Tests -------------------------------------------------------------------

describe("getOrderItemsCollectionName", () => {
  it("defaults to 'order_items' when env var is unset", () => {
    const original = process.env.ORDER_ITEMS_COLLECTION;
    delete process.env.ORDER_ITEMS_COLLECTION;
    try {
      expect(getOrderItemsCollectionName()).toBe("order_items");
    } finally {
      if (original !== undefined) process.env.ORDER_ITEMS_COLLECTION = original;
    }
  });

  it("returns the env var when set (e.g. order_items_v2)", () => {
    process.env.ORDER_ITEMS_COLLECTION = "order_items_v2";
    try {
      expect(getOrderItemsCollectionName()).toBe("order_items_v2");
    } finally {
      delete process.env.ORDER_ITEMS_COLLECTION;
    }
  });
});

describe("createOrderFromQuote", () => {
  it("returns the existing order when one already references the quote", async () => {
    // Pre-seed an existing order in the store; dedupe check should find it
    // and short-circuit before the rest of the pipeline runs.
    await pbMock.collection("orders").create({
      id: "order-1",
      quote: "quote-abc",
      order_number: "ORD-2025-01-001",
    });

    const result = await createOrderFromQuote("quote-abc");
    expect(result.already_exists).toBe(true);
    expect(result.order.id).toBe("order-1");
    expect(result.created_items).toBe(0);
  });

  it("throws when the quote has no items", async () => {
    await pbMock.collection("quotes").create({
      id: "quote-empty",
      company: "comp-1",
      customer: "cust-1",
      notes: "",
    });
    // No quote_items rows → service must throw.
    await expect(createOrderFromQuote("quote-empty")).rejects.toThrow(
      /no items to convert/,
    );
  });

  it("creates an order, copies every quote_item, and sets the right defaults", async () => {
    // Seed the dependencies in the mock store.
    await pbMock.collection("quotes").create({
      id: "quote-99",
      company: "comp-7",
      customer: "cust-3",
      notes: "Rush",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-1",
      quote: "quote-99",
      description: "Widget",
      quantity: 3,
      selling_price: 100,
      supplier: "sup-1",
      cost_price: 50,
      markup: 10,
      notes: "front",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-2",
      quote: "quote-99",
      description: "Sprocket",
      quantity: 2,
      selling_price: 75,
      supplier: "sup-2",
      cost_price: 30,
      markup: 0,
      notes: "",
    });

    const result = await createOrderFromQuote("quote-99");

    expect(result.already_exists).toBe(false);
    expect(result.created_items).toBe(2);

    // Pull the created order directly out of the store.
    const orders = await pbMock.collection("orders").getFullList();
    const created = orders.find((o) => o.quote === "quote-99") as
      | Record<string, unknown>
      | undefined;
    expect(created).toBeDefined();
    expect(created?.quote).toBe("quote-99");
    expect(created?.company).toBe("comp-7");
    expect(created?.customer).toBe("cust-3");
    expect(created?.quote_matching_attempted).toBe(true);
    expect(created?.is_repair_order).toBe(false);
    expect(created?.invoiced).toBe(false);
    // Starts at ORD-{now-year}-{now-month}-001 because the orders table
    // is empty for this test (no prior order to extend from).
    const now = new Date();
    const expectedPrefix = `ORD-${now.getFullYear()}-${String(now.getMonth() + 1).padStart(2, "0")}-`;
    expect(String(created?.order_number)).toBe(`${expectedPrefix}001`);

    // Order-item payload assertions: the two quote_items should each
    // have produced one order_item row.
    const orderItems = await pbMock.collection("order_items").getFullList();
    const ourItems = orderItems.filter((o) => o.order === created?.id);
    expect(ourItems.length).toBe(2);

    const widget = ourItems.find((o) => o.description === "Widget");
    expect(widget).toMatchObject({
      po_description: "Widget",
      quantity: 3,
      order_qty: 3,
      qty_ordered: "3",
      selling_price: 100,
      supplier: "sup-1",
      cost_price: 50,
      markup: 10,
      markup_percent: 10,
      item_status: "pending",
      status: "active",
      drv_status: "unassigned",
      notes: "front",
      quote_item: "qi-1",
    });

    const sprocket = ourItems.find((o) => o.description === "Sprocket");
    expect(sprocket?.quote_item).toBe("qi-2");
    expect(sprocket?.supplier).toBe("sup-2");
    expect(sprocket?.drv_status).toBe("unassigned");
  });

  it("extends the latest order's sequence (no month-boundary reset)", async () => {
    // The most recent order is in June; we're now in July. The contract
    // is that the next order continues June's sequence (NOT a fresh
    // July-001). The old code's bug was using `now` month, which would
    // have generated `ORD-2026-07-001` here.
    await pbMock.collection("orders").create({
      order_number: "ORD-2026-06-007",
      quote: "some-other-quote",
    });
    await pbMock.collection("quotes").create({
      id: "quote-seq",
      company: "c",
      customer: null,
      notes: "",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-1",
      quote: "quote-seq",
      description: "x",
      quantity: 1,
      selling_price: 1,
      cost_price: 0,
      markup: 0,
      notes: "",
    });

    await createOrderFromQuote("quote-seq");
    const orders = await pbMock.collection("orders").getFullList();
    const newOrder = orders.find((o) => o.quote === "quote-seq");
    expect(newOrder?.order_number).toBe("ORD-2026-06-008");
  });

  it("starts a fresh month at 001 when the orders table is empty", async () => {
    // The orders collection is empty → no most-recent order to extend
    // from. Falls back to wall-clock year/month, sequence at 001.
    await pbMock.collection("quotes").create({
      id: "q-fresh",
      company: "c",
      customer: null,
      notes: "",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-1",
      quote: "q-fresh",
      description: "x",
      quantity: 1,
      selling_price: 1,
      cost_price: 0,
      markup: 0,
      notes: "",
    });

    await createOrderFromQuote("q-fresh");
    const orders = await pbMock.collection("orders").getFullList();
    const newOrder = orders.find((o) => o.quote === "q-fresh");
    const now = new Date();
    const expected = `ORD-${now.getFullYear()}-${String(now.getMonth() + 1).padStart(2, "0")}-001`;
    expect(newOrder?.order_number).toBe(expected);
  });

  it("falls back to wall-clock year/month when the latest order_number is unparseable", async () => {
    // A junk order_number (legacy import, manual edit, or old data with a
    // different prefix) should NOT break the generator. The service
    // detects unparseable prefixes and uses now year/month.
    await pbMock.collection("orders").create({
      order_number: "GARBAGE-2026-06-007",
      quote: "old",
    });
    await pbMock.collection("quotes").create({
      id: "q-junk",
      company: "c",
      customer: null,
      notes: "",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-1",
      quote: "q-junk",
      description: "x",
      quantity: 1,
      selling_price: 1,
      cost_price: 0,
      markup: 0,
      notes: "",
    });

    await createOrderFromQuote("q-junk");
    const orders = await pbMock.collection("orders").getFullList();
    const newOrder = orders.find((o) => o.quote === "q-junk");
    const now = new Date();
    const expected = `ORD-${now.getFullYear()}-${String(now.getMonth() + 1).padStart(2, "0")}-001`;
    expect(newOrder?.order_number).toBe(expected);
  });

  it("writes to the collection named by ORDER_ITEMS_COLLECTION env var", async () => {
    process.env.ORDER_ITEMS_COLLECTION = "order_items_v2";
    await pbMock.collection("quotes").create({
      id: "q",
      company: "c",
      customer: null,
      notes: "",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-1",
      quote: "q",
      description: "x",
      quantity: 1,
      selling_price: 1,
      cost_price: 0,
      markup: 0,
      notes: "",
    });

    const result = await createOrderFromQuote("q");
    expect(result.order_items_collection).toBe("order_items_v2");

    const v2Rows = await pbMock.collection("order_items_v2").getFullList();
    expect(v2Rows.length).toBe(1);
    expect(v2Rows[0].order).toBeDefined();

    delete process.env.ORDER_ITEMS_COLLECTION;
  });

  it("concurrent calls produce unique order numbers (no race)", async () => {
    // Set up the dependencies for a single order.
    await pbMock.collection("quotes").create({
      id: "q-race",
      company: "c",
      customer: null,
      notes: "",
    });
    await pbMock.collection("quote_items").create({
      id: "qi-1",
      quote: "q-race",
      description: "x",
      quantity: 1,
      selling_price: 1,
      cost_price: 0,
      markup: 0,
      notes: "",
    });
    // Run 5 createOrderFromQuote calls in parallel against distinct
    // quotes. The counter must give each a unique number even under
    // simulated concurrency. (Note: the test mock is not actually
    // concurrent — the `await`s in the implementation interleave the
    // operations — so the assertion verifies the counter pattern, not
    // true concurrency. Real concurrency safety comes from PB's
    // `last_seq+` server-side increment.)
    const quotes = ["q-race-a", "q-race-b", "q-race-c", "q-race-d", "q-race-e"];
    for (const id of quotes) {
      await pbMock.collection("quotes").create({ id, company: "c", customer: null, notes: "" });
      await pbMock.collection("quote_items").create({
        id: `qi-${id}`,
        quote: id,
        description: "x",
        quantity: 1,
        selling_price: 1,
        cost_price: 0,
        markup: 0,
        notes: "",
      });
    }
    const results = await Promise.all(quotes.map((id) => createOrderFromQuote(id)));
    const numbers = results.map((r) => String((r.order as unknown as { order_number: string }).order_number));
    expect(new Set(numbers).size).toBe(5);
  });
});