port print-web-form app to nested flask structure

Replace stub print/ app with full PDF web print service from
~/print-web-form. Adapt UPLOAD_FOLDER to use Path(__file__).parent,
add pypdf dependency, port all tests (10 passing), remove unused static/.

print/tests/conftest.py

@@ -0,0 +1,59 @@
+import io
+import tempfile
+
+import pypdf
+import pytest
+
+from app import app as flask_app, get_pdf_page_count
+
+
+@pytest.fixture
+def app():
+    flask_app.config["TESTING"] = True
+    flask_app.config["UPLOAD_FOLDER"] = tempfile.mkdtemp()
+    flask_app.config["SECRET_KEY"] = "test-secret"
+    yield flask_app
+
+
+@pytest.fixture
+def client(app):
+    return app.test_client()
+
+
+def _make_pdf(num_pages=3):
+    writer = pypdf.PdfWriter()
+    for _ in range(num_pages):
+        writer.add_blank_page(width=612, height=792)
+    buf = io.BytesIO()
+    writer.write(buf)
+    buf.seek(0)
+    return buf
+
+
+@pytest.fixture
+def sample_pdf():
+    return _make_pdf(3).read()
+
+
+@pytest.fixture
+def large_pdf():
+    return _make_pdf(15).read()
+
+
+@pytest.fixture
+def corrupt_file():
+    return b"This is not a PDF at all"
+
+
+@pytest.fixture
+def sample_pdf_path(tmp_path):
+    path = tmp_path / "test.pdf"
+    path.write_bytes(_make_pdf(3).read())
+    return str(path)
+
+
+@pytest.fixture
+def corrupt_file_path(tmp_path):
+    path = tmp_path / "corrupt.pdf"
+    path.write_bytes(b"not a pdf")
+    return str(path)

print/tests/test_pdf_utils.py

@@ -0,0 +1,13 @@
+from app import get_pdf_page_count
+
+
+def test_page_count_valid_pdf(sample_pdf_path):
+    assert get_pdf_page_count(sample_pdf_path) == 3
+
+
+def test_page_count_corrupt_file(corrupt_file_path):
+    assert get_pdf_page_count(corrupt_file_path) is None
+
+
+def test_page_count_nonexistent_file():
+    assert get_pdf_page_count("/nonexistent/file.pdf") is None

print/tests/test_routes.py

@@ -0,0 +1,69 @@
+import io
+import os
+from unittest.mock import patch
+
+
+def test_get_index(client):
+    resp = client.get("/")
+    assert resp.status_code == 200
+    assert b"printer" in resp.data.lower() or b"upload" in resp.data.lower()
+
+
+def test_post_no_file(client):
+    resp = client.post("/", data={}, follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"No file part" in resp.data
+
+
+def test_post_empty_filename(client):
+    resp = client.post("/", data={"file": (io.BytesIO(b""), "")}, follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"No file selected" in resp.data
+
+
+def test_post_invalid_extension(client):
+    data = {"file": (io.BytesIO(b"hello"), "document.txt")}
+    resp = client.post("/", data=data, follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"Invalid file type" in resp.data
+
+
+@patch("app.subprocess.run")
+def test_post_valid_pdf(mock_run, client, app, sample_pdf):
+    mock_run.return_value.stdout = "request-id-123"
+    mock_run.return_value.stderr = ""
+    mock_run.return_value.returncode = 0
+
+    data = {"file": (io.BytesIO(sample_pdf), "test.pdf")}
+    resp = client.post("/", data=data, follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"Success" in resp.data
+
+    upload_dir = app.config["UPLOAD_FOLDER"]
+    remaining = os.listdir(upload_dir)
+    assert len(remaining) == 0
+
+    mock_run.assert_called_once()
+    cmd = mock_run.call_args[0][0]
+    assert cmd[0] == "lp"
+
+
+@patch("app.subprocess.run")
+def test_post_pdf_exceeds_max_pages(mock_run, client, large_pdf):
+    data = {"file": (io.BytesIO(large_pdf), "big.pdf")}
+    resp = client.post("/", data=data, follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"maximum allowed" in resp.data.lower()
+
+    mock_run.assert_not_called()
+
+
+def test_post_corrupt_pdf(client, app, corrupt_file):
+    data = {"file": (io.BytesIO(corrupt_file), "bad.pdf")}
+    resp = client.post("/", data=data, follow_redirects=True)
+    assert resp.status_code == 200
+    assert b"corrupt" in resp.data.lower()
+
+    upload_dir = app.config["UPLOAD_FOLDER"]
+    remaining = os.listdir(upload_dir)
+    assert len(remaining) == 0