from __future__ import annotations

import json
import re
from pathlib import Path

import pytest
from jsonschema import Draft202012Validator
from pydantic import ValidationError

from gcmd_classifier.models import (
    ArticleClassificationOutcome,
    ArticleProcessingStatus,
    ArticleResult,
    ClassificationFinalStatus,
    ClassificationRecord,
    ConfidenceMetadata,
    DeterministicValidationResult,
    OutputError,
    ProcessingMetadata,
    ReviewStatus,
    RunSummary,
    SupportType,
)

CLASSIFICATION_SCHEMA_PATH = Path("schemas/classification_result.schema.json")
RUN_SUMMARY_SCHEMA_PATH = Path("schemas/run_summary.schema.json")


def _valid_validation() -> DeterministicValidationResult:
    return DeterministicValidationResult(valid=True)


def _invalid_validation() -> DeterministicValidationResult:
    return DeterministicValidationResult(
        valid=False,
        errors=(OutputError(code="INVALID_UUID", message="UUID was not found."),),
    )


def _classification(**overrides: object) -> ClassificationRecord:
    values: dict[str, object] = {
        "UUID": "03ddc432-906d-4469-bb00-179c828dbea4",
        "name": "CARBON DIOXIDE PROFILES",
        "level": "Variable_Level_3",
        "canonical_path": "ATMOSPHERE > ATMOSPHERIC CHEMISTRY > CARBON DIOXIDE PROFILES",
        "path_components": [
            "ATMOSPHERE",
            "ATMOSPHERIC CHEMISTRY",
            "CARBON DIOXIDE PROFILES",
        ],
        "topic": "ATMOSPHERE",
        "term": "ATMOSPHERIC CHEMISTRY",
        "parent_uuid": "parent-uuid",
        "branch_id": "branch-1",
        "confidence": {"topic": 0.9, "term": 0.8, "final": 0.85},
        "classifier_evidence": (
            "The article explicitly describes atmospheric carbon dioxide profiles."
        ),
        "support_type": "explicit",
        "reason_for_stopping": "The selected concept is the deepest supported child.",
        "deterministic_validation": _valid_validation(),
        "final_status": "accepted",
        "review_required": False,
        "review_status": "not_required",
    }
    values.update(overrides)
    return ClassificationRecord.model_validate(values)


def _classified_article(**overrides: object) -> ArticleResult:
    values: dict[str, object] = {
        "DOI": "10.example/article",
        "Title": "Vertical distribution of atmospheric carbon dioxide",
        "Year": 2025,
        "Abstract": "Profiles of atmospheric carbon dioxide are evaluated.",
        "processing_status": "completed",
        "classification_outcome": "classified",
        "classifications": [_classification()],
        "review_status": "not_required",
        "processing_metadata": {
            "application_version": "0.1.0",
            "vocabulary_hash": "abc123",
            "model_provider": "fake",
            "model_name": "fake-model",
            "prompt_versions": {"topic_router": "1.0"},
            "cache_used": False,
            "title_available": True,
            "abstract_available": True,
        },
    }
    values.update(overrides)
    return ArticleResult.model_validate(values)


def test_valid_accepted_classification_record() -> None:
    record = _classification()

    assert record.final_status is ClassificationFinalStatus.ACCEPTED
    assert record.deterministic_validation.valid is True
    assert record.confidence is not None
    assert record.confidence.final == 0.85


def test_valid_reduced_to_ancestor_classification_record() -> None:
    record = _classification(
        UUID="b9c56939-c624-467d-b196-e56a5b660334",
        name="ATMOSPHERIC CHEMISTRY",
        level="Term",
        canonical_path="ATMOSPHERE > ATMOSPHERIC CHEMISTRY",
        path_components=["ATMOSPHERE", "ATMOSPHERIC CHEMISTRY"],
        final_status="reduced_to_ancestor",
        original_candidate={
            "UUID": "child-uuid",
            "canonical_path": "ATMOSPHERE > ATMOSPHERIC CHEMISTRY > CHILD",
        },
    )

    assert record.final_status is ClassificationFinalStatus.REDUCED_TO_ANCESTOR
    assert record.original_candidate is not None


def test_valid_rejected_classification_record() -> None:
    record = _classification(
        deterministic_validation=_invalid_validation(),
        final_status="rejected",
        errors=(OutputError(code="INVALID_UUID", message="UUID was not found."),),
    )

    assert record.final_status is ClassificationFinalStatus.REJECTED
    assert record.deterministic_validation.valid is False


def test_accepted_classification_requires_valid_deterministic_validation() -> None:
    with pytest.raises(ValidationError):
        _classification(deterministic_validation=_invalid_validation())


def test_valid_article_result_with_classifications() -> None:
    result = _classified_article()

    assert result.processing_status is ArticleProcessingStatus.COMPLETED
    assert result.classification_outcome is ArticleClassificationOutcome.CLASSIFIED
    assert len(result.classifications) == 1


def test_valid_minimal_no_classification_article_result() -> None:
    result = ArticleResult.model_validate(
        {
            "DOI": "10.example/no-classification",
            "Title": "Editorial note",
            "Year": 2025,
            "Abstract": "",
            "processing_status": "completed",
            "classification_outcome": "not_classified",
            "classifications": [],
            "no_classification_reason": "No defensible GCMD concept was supported.",
            "review_status": "not_required",
        }
    )

    assert result.Abstract == ""
    assert result.review_status is ReviewStatus.NOT_REQUIRED


def test_valid_failed_article_result_without_classifications() -> None:
    result = ArticleResult.model_validate(
        {
            "DOI": "10.example/failed",
            "Title": "A failed article",
            "Year": 2025,
            "Abstract": "Text.",
            "processing_status": "failed",
            "classification_outcome": None,
            "classifications": [],
            "errors": [OutputError(code="MODEL_TIMEOUT", message="Model timed out.")],
        }
    )

    assert result.processing_status is ArticleProcessingStatus.FAILED
    assert result.classifications == ()


def test_valid_partial_article_result_without_classifications() -> None:
    result = ArticleResult.model_validate(
        {
            "DOI": "10.example/partial",
            "Title": "A partially processed article",
            "Year": 2025,
            "Abstract": "Text.",
            "processing_status": "partial",
            "classification_outcome": None,
            "classifications": [],
            "warnings": [{"code": "BRANCH_FAILED", "message": "One branch failed."}],
        }
    )

    assert result.processing_status is ArticleProcessingStatus.PARTIAL
    assert result.classification_outcome is None


def test_status_scopes_do_not_accept_values_from_wrong_enum() -> None:
    with pytest.raises(ValidationError):
        ArticleResult.model_validate(
            {
                "DOI": "10.example/wrong-status",
                "Title": "Wrong status",
                "Year": 2025,
                "Abstract": "Text.",
                "processing_status": "not_classified",
                "classification_outcome": "not_classified",
                "classifications": [],
                "no_classification_reason": "No classification.",
            }
        )

    with pytest.raises(ValidationError):
        _classification(final_status="not_classified")


def test_generated_fields_use_snake_case_and_source_fields_remain_exact() -> None:
    dumped = _classified_article().model_dump(mode="json")

    assert {"DOI", "Title", "Year", "Abstract"}.issubset(dumped)
    generated_fields = set(dumped) - {"DOI", "Title", "Year", "Abstract"}
    assert generated_fields
    assert all(re.fullmatch(r"[a-z][a-z0-9_]*", field) for field in generated_fields)
    assert "processing_status" in dumped
    assert "classification_outcome" in dumped


def test_empty_abstract_is_allowed_in_article_result_output() -> None:
    result = _classified_article(Abstract="", processing_metadata={"abstract_available": False})

    assert result.Abstract == ""
    assert result.processing_metadata.abstract_available is False


def test_boolean_year_is_invalid_for_article_result() -> None:
    with pytest.raises(ValidationError):
        _classified_article(Year=True)


def test_review_compatible_values_can_be_represented_without_review_trigger_logic() -> None:
    review_record = _classification(final_status="review_required", review_required=True)
    result = _classified_article(
        classification_outcome="pending_review",
        classifications=[review_record],
        review_status="pending",
    )

    assert result.classification_outcome is ArticleClassificationOutcome.PENDING_REVIEW
    assert result.classifications[0].final_status is ClassificationFinalStatus.REVIEW_REQUIRED
    assert result.review_status is ReviewStatus.PENDING


def test_confidence_metadata_range_validation() -> None:
    assert ConfidenceMetadata(final=1.0).final == 1.0
    with pytest.raises(ValidationError):
        ConfidenceMetadata(final=1.01)


def test_schema_files_are_valid_json() -> None:
    for path in (CLASSIFICATION_SCHEMA_PATH, RUN_SUMMARY_SCHEMA_PATH):
        schema = json.loads(path.read_text())
        Draft202012Validator.check_schema(schema)


def test_minimal_no_classification_result_validates_against_json_schema() -> None:
    schema = json.loads(CLASSIFICATION_SCHEMA_PATH.read_text())
    result = ArticleResult.model_validate(
        {
            "DOI": "10.example/no-classification",
            "Title": "Editorial note",
            "Year": 2025,
            "Abstract": "",
            "processing_status": "completed",
            "classification_outcome": "not_classified",
            "classifications": [],
            "no_classification_reason": "No defensible GCMD concept was supported.",
            "review_status": "not_required",
        }
    )

    Draft202012Validator(schema).validate(result.model_dump(mode="json"))


def test_classified_result_validates_against_json_schema() -> None:
    schema = json.loads(CLASSIFICATION_SCHEMA_PATH.read_text())

    Draft202012Validator(schema).validate(_classified_article().model_dump(mode="json"))


def test_failed_result_validates_against_json_schema() -> None:
    schema = json.loads(CLASSIFICATION_SCHEMA_PATH.read_text())
    result = ArticleResult.model_validate(
        {
            "DOI": "10.example/failed",
            "Title": "Failed article",
            "Year": 2025,
            "Abstract": "Text.",
            "processing_status": "failed",
            "classification_outcome": None,
            "classifications": [],
            "errors": [{"code": "LOAD_FAILED", "message": "Article failed."}],
        }
    )

    Draft202012Validator(schema).validate(result.model_dump(mode="json"))


def test_basic_run_summary_validates_against_json_schema() -> None:
    schema = json.loads(RUN_SUMMARY_SCHEMA_PATH.read_text())
    summary = RunSummary(
        run_id="run-1",
        articles_received=3,
        articles_completed=2,
        articles_failed=1,
        accepted_classifications=2,
    )

    Draft202012Validator(schema).validate(summary.model_dump(mode="json"))


def test_processing_metadata_can_represent_title_only_input() -> None:
    metadata = ProcessingMetadata(title_available=True, abstract_available=False)

    assert metadata.title_available is True
    assert metadata.abstract_available is False


def test_support_type_enum_values_are_schema_compatible() -> None:
    record = _classification(support_type=SupportType.MIXED)

    assert record.support_type is SupportType.MIXED