"""Unit tests for src/shared/shared/pdf.py (weekly summary PDF generator)."""

import pytest
from fpdf import FPDF as _RealFPDF

from shared.pdf import build_weekly_summary_pdf


class _NoCompressFPDF(_RealFPDF):
    """FPDF subclass with stream compression off, so the content stream holds
    readable text we can assert against without a PDF parser."""

    last_pages_count = 0

    def __init__(self, *args, **kwargs):
        super().__init__(*args, **kwargs)
        self.set_compression(False)

    def output(self, *args, **kwargs):
        _NoCompressFPDF.last_pages_count = self.pages_count
        return super().output(*args, **kwargs)


@pytest.fixture()
def readable_pdf(monkeypatch):
    """Patch the generator to emit uncompressed (searchable) PDFs."""
    monkeypatch.setattr("shared.pdf.FPDF", _NoCompressFPDF)


def _orders():
    return [
        {
            "employee_name": "Bob Jones",
            "employee_email": "bob@seahavenind.com",
            "items": [
                {"name": "Chicken Parm", "quantity": 2},
                {"name": "Caesar Salad", "quantity": 1},
            ],
        },
        {
            "employee_name": "Alice Smith",
            "employee_email": "alice@seahavenind.com",
            "items": [{"name": "Veggie Bowl", "quantity": 3}],
        },
    ]


def _build(orders, **overrides):
    kwargs = {
        "week": "2026-W19",
        "generated_at": "2026-05-22T16:35:40-04:00",
        "total_employees": len(orders),
        "total_meals": sum(i["quantity"] for o in orders for i in o["items"]),
    }
    kwargs.update(overrides)
    return build_weekly_summary_pdf(orders, **kwargs)


def _volume_orders(count, items_per_employee=2):
    """Synthetic orders for layout/page-count checks."""
    return [
        {
            "employee_name": f"Employee {i:02d}",
            "employee_email": f"emp{i:02d}@seahavenind.com",
            "items": [
                {"name": f"Meal {j}", "quantity": 1} for j in range(items_per_employee)
            ],
        }
        for i in range(count)
    ]


class TestPdfStructure:
    def test_returns_pdf_bytes(self):
        pdf = _build(_orders())
        assert isinstance(pdf, bytes)
        assert pdf[:5] == b"%PDF-", "Output should be a valid PDF"
        assert len(pdf) > 0

    def test_empty_orders_still_valid_pdf(self):
        pdf = _build([], total_employees=0, total_meals=0)
        assert pdf[:5] == b"%PDF-"


class TestPdfContent:
    def test_header_shows_week_and_counts(self, readable_pdf):
        pdf = _build(_orders())
        text = pdf.decode("latin-1")
        assert "Weekly Meal Order Summary - 2026-W19" in text
        assert "2 employees" in text
        assert "6 meals" in text

    def test_each_employee_and_item_present(self, readable_pdf):
        orders = _orders()
        pdf = _build(orders)
        text = pdf.decode("latin-1")
        for order in orders:
            assert order["employee_name"] in text, f"missing {order['employee_name']}"
            assert order["employee_email"] in text
            for item in order["items"]:
                assert item["name"] in text, f"missing item {item['name']}"

    def test_no_prices_anywhere(self, readable_pdf):
        """Per issue #16: strictly employee, item, qty — never a price."""
        orders = _orders()
        # Even if price fields are present on the items, they must not be rendered.
        for o in orders:
            for i in o["items"]:
                i["price"] = 12.50
                i["subtotal"] = 99.99
        pdf = _build(orders)
        text = pdf.decode("latin-1")
        assert "$" not in text, "PDF must contain no currency symbol"
        assert "12.50" not in text and "99.99" not in text, "PDF must not render prices"

    def test_non_latin1_chars_do_not_crash(self):
        orders = [
            {
                "employee_name": "José 🍜 Ramírez",
                "employee_email": "jose@seahavenind.com",
                "items": [{"name": "Phở Bowl", "quantity": 1}],
            }
        ]
        pdf = _build(orders)
        assert pdf[:5] == b"%PDF-"


class TestPdfLayout:
    def test_typical_week_fits_on_one_page(self, readable_pdf):
        """12 employees with 2 items each overflowed the pre-DEV-210 layout."""
        pdf = _build(_volume_orders(12))
        assert pdf[:5] == b"%PDF-"
        assert _NoCompressFPDF.last_pages_count == 1

    def test_high_volume_still_paginates(self, readable_pdf):
        pdf = _build(_volume_orders(40))
        assert pdf[:5] == b"%PDF-"
        assert _NoCompressFPDF.last_pages_count >= 2