"""Pins the search syntax that ``docs/usage.md`` promises users.

Every query here appears verbatim, or as a direct paraphrase, in the
"Document searches" section of ``docs/usage.md``. Each case indexes real
documents and asserts on matched document IDs rather than on the parsed
query, because a query that parses cleanly is not necessarily a query that
means what the documentation says it means: ``added:now`` parses without a
single diagnostic and then matches nothing, because it resolves to an
instant rather than to a span.

The negative cases matter as much as the positive ones. They pin the
behaviours the docs explicitly warn about, so that if any of them ever
starts working the warning can be removed deliberately rather than being
left standing as a lie.
"""

from __future__ import annotations

from datetime import UTC
from datetime import datetime
from typing import TYPE_CHECKING

import pytest
import time_machine

from documents.models import Document
from documents.models import Note
from documents.models import Tag
from documents.search._errors import InvalidDateQuery

if TYPE_CHECKING:
    from collections.abc import Generator

    from django.contrib.auth.models import User

    from documents.search._backend import TantivyBackend

pytestmark = [pytest.mark.search, pytest.mark.django_db]

# A Monday, so that "next monday"/"last monday" land a clean week either side.
FROZEN_NOW = datetime(2026, 6, 15, 12, 0, tzinfo=UTC)

# The checksum used in the docs' `checksum:` example.
DOC_CHECKSUM = "9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08"


def _matched_ids(backend: TantivyBackend, query: str) -> set[int]:
    return set(backend.search_ids(query, user=None))


def _index(backend: TantivyBackend, **kwargs: object) -> Document:
    doc = Document.objects.create(**kwargs)
    backend.add_or_update(doc)
    return doc


class TestLogicalExpressions:
    @pytest.fixture
    def docs(self, backend: TantivyBackend) -> dict[str, int]:
        return {
            "secret": _index(
                backend,
                title="Invoice one",
                content="invoice secret contents",
                checksum="doc-syntax-secret",
            ).pk,
            "plain": _index(
                backend,
                title="Invoice two",
                content="invoice ordinary contents",
                checksum="doc-syntax-plain",
            ).pk,
        }

    def test_not_excludes_a_term(
        self,
        backend: TantivyBackend,
        docs: dict[str, int],
    ) -> None:
        """
        GIVEN:
            - Two indexed documents, one containing "secret" and one not
        WHEN:
            - "invoice NOT secret" is searched, as docs/usage.md documents
        THEN:
            - Only the document without "secret" matches
        """
        assert _matched_ids(backend, "invoice NOT secret") == {docs["plain"]}

    def test_leading_hyphen_requires_the_term_instead_of_excluding_it(
        self,
        backend: TantivyBackend,
        docs: dict[str, int],
    ) -> None:
        """
        GIVEN:
            - Two indexed documents, one containing "secret" and one not
        WHEN:
            - "invoice -secret" is searched (a leading hyphen, not "NOT")
        THEN:
            - Only the document containing "secret" matches, because
              separators are stripped at index time, so "-secret" is
              indexed as the plain term "secret" and the query becomes an
              AND rather than an exclusion, exactly as the docs warn
        """
        assert _matched_ids(backend, "invoice -secret") == {docs["secret"]}

    def test_or_inside_parentheses_matches_either_branch(
        self,
        backend: TantivyBackend,
        docs: dict[str, int],
    ) -> None:
        """
        GIVEN:
            - Two indexed documents, one containing "secret" and one
              containing "ordinary"
        WHEN:
            - "invoice AND (secret OR ordinary)" is searched
        THEN:
            - Both documents match
        """
        matched = _matched_ids(backend, "invoice AND (secret OR ordinary)")
        assert matched == {docs["secret"], docs["plain"]}


class TestPhraseSearch:
    def test_quoted_phrase_requires_the_words_in_order(
        self,
        backend: TantivyBackend,
    ) -> None:
        """
        GIVEN:
            - A document whose content contains "the quick brown fox jumps"
        WHEN:
            - A quoted phrase is searched, in order and out of order
        THEN:
            - The in-order phrase matches, and the same words reordered do
              not
        """
        doc = _index(
            backend,
            title="Phrase",
            content="the quick brown fox jumps",
            checksum="doc-syntax-phrase",
        )
        assert _matched_ids(backend, '"quick brown fox"') == {doc.pk}
        assert _matched_ids(backend, '"brown quick fox"') == set()


class TestTagCommaList:
    """``tag:bills,unpaid`` is published syntax (docs/usage.md), so this checks
    that the documented spelling still returns what the docs promise: only the
    document carrying every listed tag.

    It is deliberately not proof of paperless's field configuration, and must
    not be read as such. Removing ``comma_values`` from the ``tag`` FieldSpec
    leaves this test passing, because paperless's analyzer splits the literal
    value "bills,unpaid" into the same two tokens the value-list reading
    produces, so the two readings select the same documents. The registry fact
    -- that ``tag`` opts in and no other field does -- is observable only at
    the registry, and is owned by test_registry.py's
    ``test_tag_is_comma_values``/``test_correspondent_is_not_comma_values``.
    """

    def test_comma_list_requires_every_listed_tag(
        self,
        backend: TantivyBackend,
    ) -> None:
        """
        GIVEN:
            - A document carrying both "bills" and "unpaid" tags, and a
              second document carrying only "bills" (plus "archived")
        WHEN:
            - "tag:bills,unpaid" is searched
        THEN:
            - Only the document carrying every listed tag matches, and a
              single-tag "tag:bills" search still matches both documents
        """
        bills = Tag.objects.create(name="bills")
        unpaid = Tag.objects.create(name="unpaid")
        archived = Tag.objects.create(name="archived")

        both = Document.objects.create(
            title="Both tags",
            content="body",
            checksum="doc-syntax-tag-both",
        )
        both.tags.add(bills, unpaid)
        backend.add_or_update(both)

        one = Document.objects.create(
            title="One tag",
            content="body",
            checksum="doc-syntax-tag-one",
        )
        one.tags.add(bills, archived)
        backend.add_or_update(one)

        assert _matched_ids(backend, "tag:bills,unpaid") == {both.pk}
        assert _matched_ids(backend, "tag:bills") == {both.pk, one.pk}


class TestArchiveMetadataFields:
    @pytest.fixture
    def doc(self, backend: TantivyBackend, admin_user: User) -> Document:
        doc = Document.objects.create(
            title="Metadata",
            content="body",
            checksum=DOC_CHECKSUM,
            archive_serial_number=100,
            page_count=12,
            original_filename="invoice.pdf",
        )
        Note.objects.create(document=doc, user=admin_user, note="a note")
        backend.add_or_update(doc)
        return doc

    @pytest.mark.parametrize(
        "query",
        [
            "asn:100",
            "asn:[50 to 150]",
            "page_count:12",
            "page_count:[10 to 20]",
            "num_notes:1",
            "num_notes:[1 to 5]",
            "original_filename:invoice.pdf",
            f"checksum:{DOC_CHECKSUM}",
            "checksum:9f86d081*",
            # A checksum term is stored verbatim, but a checksum *pattern* is
            # lowercased before it is matched, which the docs now say outright
            # next to the "only a complete, lowercase checksum matches" rule
            # that the uppercase term in the negative list below pins.
            "checksum:9F86D081*",
        ],
    )
    def test_documented_metadata_query_matches(
        self,
        backend: TantivyBackend,
        doc: Document,
        query: str,
    ) -> None:
        """
        GIVEN:
            - A document with an ASN, page count, a note, an original
              filename and a known checksum
        WHEN:
            - Every documented metadata-field spelling (exact value,
              range, and, for checksum, a lowercase prefix pattern
              regardless of the case the pattern itself is typed in) is
              searched
        THEN:
            - Each one matches the document
        """
        assert _matched_ids(backend, query) == {doc.pk}

    @pytest.mark.parametrize(
        "query",
        [
            # The docs say only a complete, lowercase checksum matches.
            "checksum:9f86d081",
            f"checksum:{DOC_CHECKSUM.upper()}",
        ],
    )
    def test_partial_or_uppercase_checksum_matches_nothing(
        self,
        backend: TantivyBackend,
        doc: Document,
        query: str,
    ) -> None:
        """
        GIVEN:
            - A document with a known, complete, lowercase checksum
        WHEN:
            - An exact-value search is run with a partial or uppercase
              spelling of that checksum
        THEN:
            - Nothing matches, as the docs say only a complete, lowercase
              checksum matches as an exact value
        """
        assert _matched_ids(backend, query) == set()


class TestDocumentedDateForms:
    @pytest.fixture(autouse=True)
    def frozen_now(self) -> Generator[None, None, None]:
        with time_machine.travel(FROZEN_NOW, tick=False):
            yield

    @pytest.fixture
    def dated(self, backend: TantivyBackend) -> dict[str, int]:
        stamps = {
            "today": datetime(2026, 6, 15, 9, 0, tzinfo=UTC),
            "yesterday": datetime(2026, 6, 14, 9, 0, tzinfo=UTC),
            "tomorrow": datetime(2026, 6, 16, 9, 0, tzinfo=UTC),
            "next_monday": datetime(2026, 6, 22, 10, 0, tzinfo=UTC),
            "last_monday": datetime(2026, 6, 8, 10, 0, tzinfo=UTC),
            "january": datetime(2026, 1, 10, 10, 0, tzinfo=UTC),
            "old": datetime(2005, 3, 4, 15, 30, tzinfo=UTC),
        }
        return {
            label: _index(
                backend,
                title=label,
                content="dated body",
                checksum=f"doc-syntax-date-{label}",
                added=stamp,
            ).pk
            for label, stamp in stamps.items()
        }

    @pytest.mark.parametrize(
        ("query", "label"),
        [
            ("added:today", "today"),
            ("added:yesterday", "yesterday"),
            ("added:tomorrow", "tomorrow"),
            ('added:"next monday"', "next_monday"),
            ('added:"last monday"', "last_monday"),
            ("added:january", "january"),
            ("added:2005-03-04", "old"),
            ("added:2005-03", "old"),
            ("added:[2005-01-01 to 2005-12-31]", "old"),
            ("added:[2005 to 2009]", "old"),
            # A full timestamp works, but only quoted when it stands alone,
            # and only unquoted when it is a range bound. The bare standalone
            # spelling is pinned as a non-match below.
            ('added:"2005-03-04T15:30:00Z"', "old"),
            ("added:[2005-03-04T09:00:00Z to 2005-03-04T17:00:00Z]", "old"),
            # A quoted range bound works when the quotes are single ones; the
            # double-quoted spelling is pinned as an error below.
            ("added:['2005-03-04' to 2005-03-05]", "old"),
        ],
    )
    def test_documented_date_form_matches_its_day_or_month(
        self,
        backend: TantivyBackend,
        dated: dict[str, int],
        query: str,
        label: str,
    ) -> None:
        """
        GIVEN:
            - Documents dated today, yesterday, tomorrow, next/last
              Monday, in January, and on an old fixed date, indexed
              against a frozen "now" (a Monday)
        WHEN:
            - Every documented date-form spelling is searched: relative
              keywords, quoted multi-word phrases, a bare year-month, an
              explicit range, a quoted full timestamp standing alone, an
              unquoted full timestamp as a range bound, and a
              single-quoted range bound
        THEN:
            - Each form matches exactly the document dated on its day or
              within its month
        """
        assert _matched_ids(backend, query) == {dated[label]}

    @pytest.mark.parametrize(
        "query",
        [
            # Zero-width: these resolve to a single instant, not a span, so
            # nothing in a realistic corpus lands on them. The docs warn
            # about them rather than presenting them as usable.
            "added:now",
            "added:noon",
            "added:midnight",
            # Quoting is what rescues the other multi-word date expressions,
            # so pin that it does not rescue these: the problem is the width
            # of the resulting range, not the way the value is delimited.
            # One quoted spelling is enough for that; which keyword sits
            # inside the quotes is grammar whoosh-compat owns.
            'added:"now"',
            # A relative offset, which the warning in the docs names by this
            # exact spelling. Standing alone it is an instant like the rest of
            # this list; the same offset used as a range bound is a real
            # window, pinned by the test below.
            'added:"-1 week"',
        ],
    )
    def test_forms_the_docs_warn_about_match_nothing(
        self,
        backend: TantivyBackend,
        dated: dict[str, int],
        query: str,
    ) -> None:
        """
        GIVEN:
            - A realistic dated corpus (see the `dated` fixture)
        WHEN:
            - A zero-width date form ("now", "noon", "midnight", a quoted
              "now") or a standalone relative offset ("-1 week") is
              searched: each resolves to a single instant rather than a
              span, and quoting does not rescue them the way it rescues
              other multi-word date expressions, since the problem is the
              width of the resulting range, not how the value is
              delimited
        THEN:
            - Nothing matches, exactly as the docs warn, rather than
              presenting these as usable spellings
        """
        assert _matched_ids(backend, query) == set()

    def test_bare_timestamp_is_rejected_rather_than_matching_nothing(
        self,
        backend: TantivyBackend,
        dated: dict[str, int],
    ) -> None:
        """
        GIVEN:
            - A realistic dated corpus, including a document dated at a
              known full timestamp
        WHEN:
            - The bare, unquoted spelling of that full timestamp is
              searched (the quoted and range-bound spellings pinned above
              do work and match this fixture's document)
        THEN:
            - `InvalidDateQuery` is raised rather than the query silently
              matching nothing, since this is a user-fixable error the
              docs tell the user to quote, and the reported value is the
              whole contiguous fragment the user typed, not just the
              prefix the date grammar's tokenizer first split on
        """
        with pytest.raises(InvalidDateQuery) as exc_info:
            _matched_ids(backend, "added:2005-03-04T15:30:00Z")
        assert exc_info.value.field == "added"
        assert exc_info.value.value == "2005-03-04T15:30:00Z"

    def test_relative_offset_as_a_range_bound_is_a_real_window(
        self,
        backend: TantivyBackend,
        dated: dict[str, int],
    ) -> None:
        """
        GIVEN:
            - A realistic dated corpus, including a document dated two
              hours before a "last Monday to now" window opens, and
              documents dated today and yesterday, inside that window
        WHEN:
            - "added:['-1 week' to now]" is searched: the same offset
              that matches nothing standing alone (see the test above),
              used here as a range bound instead
        THEN:
            - The window matches today and yesterday but excludes the
              document two hours before it opens, showing the bound is
              the offset itself and not a whole-day rounding of it, as
              the docs say next to the warning about the standalone form
        """
        assert _matched_ids(backend, "added:['-1 week' to now]") == {
            dated["today"],
            dated["yesterday"],
        }

    def test_double_quoted_range_bound_is_rejected(
        self,
        backend: TantivyBackend,
        dated: dict[str, int],
    ) -> None:
        """
        GIVEN:
            - A realistic dated corpus
        WHEN:
            - A range bound is double-quoted rather than single-quoted
              ("added:[\"2005-03-04\" to 2005-03-05]")
        THEN:
            - `InvalidDateQuery` is raised, pinning which of the two
              quote characters fails: quoting a range bound is allowed,
              but only with single quotes, since the double-quoted
              spelling reaches the date grammar with its quotes still
              attached and is not a recognizable date
        """
        with pytest.raises(InvalidDateQuery) as exc_info:
            _matched_ids(backend, 'added:["2005-03-04" to 2005-03-05]')
        assert exc_info.value.value == '"2005-03-04"'