"""批次 A（P0 前端配套）后端补口测试。

覆盖：
1. 商品可用单位接口 `GET /catalog/products/<id>/units/`（含换算率与按 rate 的销售价）
2. 销售开单动作接口 `create-bill` / `confirm`（含 402 信用超限、最低售价 400）
3. 采购开单动作接口 `create-bill`（批次号/到期日穿透）/ `confirm`
4. 对账单客户侧 HTML（匿名可访问、含金额、可打印）
5. 对账单分享吊销接口
6. 打印渲染器 `{{#if}}`/`{{else}}` 与批次号列
"""

import pytest
from datetime import date
from decimal import Decimal
from model_bakery import baker
from rest_framework.test import APIClient
from rest_framework_simplejwt.tokens import RefreshToken

from apps.catalog.models import Product, Unit, UnitConversion
from apps.inventory.models import Stock, StockBatch, Warehouse
from apps.partner.models import Customer, Supplier
from apps.finance.models import StatementShare
from apps.printing.renderer import render_template


@pytest.fixture
def auth_client(db, user, tenant):
    c = APIClient()
    refresh = RefreshToken.for_user(user)
    c.credentials(
        HTTP_AUTHORIZATION=f"Bearer {refresh.access_token}",
        HTTP_X_TENANT_ID=tenant.code,
    )
    return c


@pytest.fixture
def anon_client(db):
    """同步匿名客户端（覆盖 conftest 的 async 版本，便于在同步用例里断言匿名访问）。"""
    return APIClient()


@pytest.fixture
def warehouse(db, tenant):
    return baker.make(Warehouse, tenant=tenant, code="WH01", name="主仓")


@pytest.fixture
def product(db, tenant):
    """基本单位"瓶"，换算"箱"=24，默认售价 5。"""
    base = baker.make(Unit, tenant=tenant, code="bottle", name="瓶", is_base=True)
    p = baker.make(Product, tenant=tenant, code="P001", name="可乐",
                   sale_price=Decimal("5"), base_unit=base)
    box = baker.make(Unit, tenant=tenant, code="box", name="箱", is_base=False)
    UnitConversion.objects.create(tenant=tenant, product=p, unit=box, rate=Decimal("24"))
    return p


@pytest.fixture
def batch_product(db, tenant):
    p = baker.make(Product, tenant=tenant, code="B001", name="鲜奶",
                   sale_price=Decimal("10"), is_batch_managed=True,
                   shelf_life_days=30)
    return p


@pytest.fixture
def customer(db, tenant):
    return baker.make(Customer, tenant=tenant, code="C001", name="张三商店",
                      credit_limit=Decimal("0"))


@pytest.fixture
def supplier(db, tenant):
    return baker.make(Supplier, tenant=tenant, code="S001", name="上游厂")


def _stock_in(tenant, warehouse, product, qty, unit_cost="2"):
    from apps.inventory import services as inv_services
    inv_services.inbound(
        tenant=tenant, warehouse=warehouse, product=product,
        quantity=Decimal(str(qty)), unit_cost=Decimal(unit_cost),
    )


# ---------- 1. 商品可用单位 ----------


def test_product_units_api(db, auth_client, product):
    resp = auth_client.get(f"/api/v1/catalog/products/{product.id}/units/")
    assert resp.status_code == 200, resp.content
    body = resp.json()
    assert body["base_unit_name"] == "瓶"
    assert Decimal(body["sale_price"]) == Decimal("5")
    assert body["is_batch_managed"] is False
    units = {u["unit_name"]: u for u in body["units"]}
    assert Decimal(units["瓶"]["rate"]) == Decimal("1")
    assert Decimal(units["箱"]["rate"]) == Decimal("24")
    # 箱价 = 基本价 × 24
    assert Decimal(units["箱"]["price"]) == Decimal("120")
    assert units["箱"]["is_base"] is False


# ---------- 2. 销售开单/过账 ----------


def test_sales_create_bill_with_unit_and_round_off(
    db, auth_client, tenant, warehouse, customer, product
):
    """2 箱 × 单价 120.5（录入单位计价）+ 抹零，落库金额与基本单位数量正确。"""
    _stock_in(tenant, warehouse, product, 100)
    box = UnitConversion.objects.get(product=product).unit
    resp = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id,
        "warehouse": warehouse.id,
        "round_to": "1",
        "lines": [{
            "product": product.id, "quantity": 2, "unit_price": "120.5",
            "source_unit": box.id,
        }],
    }, format="json")
    assert resp.status_code == 201, resp.content
    body = resp.json()
    assert body["state"] == "draft"
    # 241.0 抹到元 → 净额 241，抹零额…241 已是整数，故用 120.6 让结果非整
    assert Decimal(body["total_amount"]) == Decimal("241")
    line = body["lines"][0]
    assert Decimal(line["quantity"]) == Decimal("48")        # 2 × 24
    assert Decimal(line["source_quantity"]) == Decimal("2")
    assert line["unit_name"] == "箱"


def test_sales_create_bill_round_off_amount(
    db, auth_client, tenant, warehouse, customer, product
):
    """抹零落到分/角/元三档：241.36 → 抹元 241（抹零 0.36）。"""
    _stock_in(tenant, warehouse, product, 100)
    resp = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id, "round_to": "1",
        "lines": [{"product": product.id, "quantity": 2, "unit_price": "120.68"}],
    }, format="json")
    assert resp.status_code == 201, resp.content
    body = resp.json()
    assert Decimal(body["total_amount"]) == Decimal("241")
    assert Decimal(body["round_off"]) == Decimal("0.36")


def test_sales_create_bill_auto_price_when_missing(
    db, auth_client, tenant, warehouse, customer, product
):
    """不传单价 → 自动取默认售价（无录入单位时按基本单位价）。"""
    _stock_in(tenant, warehouse, product, 100)
    resp = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id,
        "lines": [{"product": product.id, "quantity": 3}],
    }, format="json")
    assert resp.status_code == 201, resp.content
    line = resp.json()["lines"][0]
    assert Decimal(line["unit_price"]) == Decimal("5")
    assert Decimal(line["amount"]) == Decimal("15")


def test_sales_create_bill_below_min_price_400(
    db, auth_client, tenant, warehouse, customer, product
):
    product.min_sale_price = Decimal("8")
    product.save()
    resp = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id,
        "lines": [{"product": product.id, "quantity": 1, "unit_price": "5"}],
    }, format="json")
    assert resp.status_code == 400
    body = resp.json()
    assert body["code"] == "below_min_price"
    assert body["product_code"] == "P001"


def test_sales_create_bill_below_min_price_allowed(
    db, auth_client, tenant, warehouse, customer, product
):
    """行带 allow_below_min=true → 审批放行。"""
    product.min_sale_price = Decimal("8")
    product.save()
    _stock_in(tenant, warehouse, product, 10)
    resp = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id,
        "lines": [{"product": product.id, "quantity": 1, "unit_price": "5",
                   "allow_below_min": True}],
    }, format="json")
    assert resp.status_code == 201, resp.content


def test_sales_confirm_bill_api_deducts_stock(
    db, auth_client, tenant, warehouse, customer, product
):
    _stock_in(tenant, warehouse, product, 10)
    create = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id,
        "lines": [{"product": product.id, "quantity": 4, "unit_price": "5"}],
    }, format="json").json()
    resp = auth_client.post(f"/api/v1/sales/bills/{create['id']}/confirm/", {}, format="json")
    assert resp.status_code == 200, resp.content
    assert resp.json()["state"] == "confirmed"
    assert Stock.objects.get(product=product).on_hand == Decimal("6")


def test_sales_confirm_over_credit_402_then_force(
    db, auth_client, tenant, warehouse, product
):
    """信用超限返回 402 + code，force=true 放行。"""
    limited = baker.make(Customer, tenant=tenant, code="C999", name="受限客户",
                         credit_limit=Decimal("100"))
    from apps.finance.models import Receivable
    baker.make(Receivable, tenant=tenant, customer=limited, bill_no="RC-OLD",
               bill_date=date.today(), total_amount=Decimal("80"), status="open")
    _stock_in(tenant, warehouse, product, 10)
    create = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": limited.id, "warehouse": warehouse.id,
        "lines": [{"product": product.id, "quantity": 10, "unit_price": "5"}],
    }, format="json").json()
    resp = auth_client.post(f"/api/v1/sales/bills/{create['id']}/confirm/", {}, format="json")
    assert resp.status_code == 402
    body = resp.json()
    assert body["code"] == "credit_limit_exceeded"
    assert body["customer_code"] == "C999"
    # 未放行：库存未扣
    assert Stock.objects.get(product=product).on_hand == Decimal("10")
    # 强制过账
    resp2 = auth_client.post(f"/api/v1/sales/bills/{create['id']}/confirm/",
                             {"force": True}, format="json")
    assert resp2.status_code == 200, resp2.content
    assert resp2.json()["state"] == "confirmed"


# ---------- 3. 采购开单/过账（批次） ----------


def test_purchase_create_and_confirm_with_batch(
    db, auth_client, tenant, warehouse, supplier, batch_product
):
    resp = auth_client.post("/api/v1/purchase/bills/create-bill/", {
        "supplier": supplier.id, "warehouse": warehouse.id,
        "lines": [{
            "product": batch_product.id, "quantity": 12, "unit_price": "6",
            "batch_no": "B20260901", "production_date": "2026-09-01",
            "expiry_date": "2026-10-01",
        }],
    }, format="json")
    assert resp.status_code == 201, resp.content
    bill = resp.json()
    assert bill["lines"][0]["batch_no"] == "B20260901"
    assert bill["lines"][0]["is_batch_managed"] is True

    resp2 = auth_client.post(f"/api/v1/purchase/bills/{bill['id']}/confirm/", {}, format="json")
    assert resp2.status_code == 200, resp2.content
    assert resp2.json()["state"] == "confirmed"
    sb = StockBatch.objects.get(product=batch_product, batch_no="B20260901")
    assert sb.on_hand == Decimal("12")
    assert sb.expiry_date == date(2026, 10, 1)


def test_purchase_batch_managed_missing_batch_no_400(
    db, auth_client, tenant, warehouse, supplier, batch_product
):
    """批次商品漏填批次号 → 服务层拒绝，接口翻译为 400。"""
    resp = auth_client.post("/api/v1/purchase/bills/create-bill/", {
        "supplier": supplier.id, "warehouse": warehouse.id,
        "lines": [{"product": batch_product.id, "quantity": 5, "unit_price": "6"}],
    }, format="json")
    assert resp.status_code == 201  # 建单阶段不校验批次（过账才校验）
    bill_id = resp.json()["id"]
    resp2 = auth_client.post(f"/api/v1/purchase/bills/{bill_id}/confirm/", {}, format="json")
    assert resp2.status_code == 400, resp2.content


# ---------- 4. 对账单客户侧 HTML ----------


def test_public_statement_html(db, auth_client, anon_client, tenant, customer):
    from apps.finance.models import Receivable
    baker.make(Receivable, tenant=tenant, customer=customer, bill_no="RC001",
               bill_date=date.today(), total_amount=Decimal("1234.5"), status="open")
    share = baker.make(
        StatementShare, tenant=tenant, customer=customer,
        date_from=date.today(), date_to=date.today(),
    )
    resp = anon_client.get(f"/api/v1/open/statements/{share.token}/?view=html")
    assert resp.status_code == 200, resp.content
    assert resp["Content-Type"].startswith("text/html")
    html_text = resp.content.decode("utf-8")
    assert "对 账 单" in html_text
    assert "张三商店" in html_text
    assert "1,234.50" in html_text          # 金额千分位
    assert "window.print()" in html_text    # 可打印
    assert "RC001" in html_text


def test_public_statement_json_still_works(db, auth_client, anon_client, tenant, customer):
    share = baker.make(
        StatementShare, tenant=tenant, customer=customer,
        date_from=date.today(), date_to=date.today(),
    )
    resp = anon_client.get(f"/api/v1/open/statements/{share.token}/")
    assert resp.status_code == 200
    assert resp.json()["customer"]["code"] == "C001"


def test_statement_share_revoke_api(db, auth_client, anon_client, tenant, customer):
    resp = auth_client.post("/api/v1/finance/statements/share/", {
        "customer_id": customer.id,
        "date_from": date.today().isoformat(),
        "date_to": date.today().isoformat(),
        "expires_days": 7,
    }, format="json")
    assert resp.status_code == 201, resp.content
    token = resp.json()["token"]
    assert anon_client.get(f"/api/v1/open/statements/{token}/").status_code == 200

    resp2 = auth_client.post(f"/api/v1/finance/statements/share/{token}/revoke/", {},
                             format="json")
    assert resp2.status_code == 200, resp2.content
    assert resp2.json()["revoked"] is True
    assert anon_client.get(f"/api/v1/open/statements/{token}/").status_code == 404


# ---------- 5. 渲染器 if/else ----------


def test_renderer_if_block():
    ctx = {"a": 1, "b": "", "lines": []}
    assert render_template("{{#if a}}有{{/if}}", ctx) == "有"
    assert render_template("{{#if b}}有{{/if}}", ctx) == ""
    assert render_template("{{#if b}}有{{else}}无{{/if}}", ctx) == "无"
    assert render_template("{{#if lines}}有{{else}}无{{/if}}", ctx) == "无"
    # 嵌套
    assert render_template("{{#if a}}{{#if b}}AB{{else}}A{{/if}}{{/if}}", ctx) == "A"


def test_renderer_if_inside_each():
    ctx = {"lines": [{"n": "A", "batch": "B1"}, {"n": "B", "batch": ""}]}
    body = "{{#each lines}}[{{item.n}}{{#if item.batch}}:{{item.batch}}{{/if}}]{{/each}}"
    assert render_template(body, ctx) == "[A:B1][B]"


# ---------- 6. 打印批次列 ----------


def test_print_sales_bill_has_batch_column(
    db, auth_client, tenant, warehouse, customer, batch_product
):
    """批次商品的销售单打印带批次号（FEFO 分摊结果）。"""
    from apps.inventory import services as inv_services
    inv_services.inbound(
        tenant=tenant, warehouse=warehouse, product=batch_product,
        quantity=Decimal("10"), unit_cost=Decimal("4"),
        batch_no="BATCH-A", expiry_date=date(2026, 12, 31),
    )
    create = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id,
        "lines": [{"product": batch_product.id, "quantity": 3, "unit_price": "10"}],
    }, format="json").json()
    auth_client.post(f"/api/v1/sales/bills/{create['id']}/confirm/", {}, format="json")

    resp = auth_client.get(f"/api/v1/printing/render/sales_bill/{create['id']}/?autoprint=0")
    assert resp.status_code == 200
    html_text = resp.content.decode("utf-8")
    assert "批次号" in html_text
    assert "BATCH-A" in html_text


def test_print_non_batch_no_batch_column(
    db, auth_client, tenant, warehouse, customer, product
):
    """非批次商品不出现批次号列。"""
    _stock_in(tenant, warehouse, product, 10)
    create = auth_client.post("/api/v1/sales/bills/create-bill/", {
        "customer": customer.id, "warehouse": warehouse.id,
        "lines": [{"product": product.id, "quantity": 2, "unit_price": "5"}],
    }, format="json").json()
    auth_client.post(f"/api/v1/sales/bills/{create['id']}/confirm/", {}, format="json")
    resp = auth_client.get(f"/api/v1/printing/render/sales_bill/{create['id']}/?autoprint=0")
    assert "批次号" not in resp.content.decode("utf-8")