"""I2 Step 1 tests — fail-fast ingest-manifest contract (spec §4, verdict reservation §3).

Every malformed manifest raises at validation, BEFORE any source access (the startup-contract
discipline of method spec §10 / ingest spec §4 and §9's technical gate). The verdict-layer
reservation (okf_type != verdict, case-insensitive) is enforced here — at the contract, never
downstream — closing session-plan key assumption 2 (fail-fast manifest validation without
network). Pattern: tests/test_contracts.py (inline dict constants + pytest.raises per
malformation; fail-fast ordering proof mirrors test_no_chat_client_call_on_malformed_contract).
"""

import copy
import hashlib
import json
from pathlib import Path
from typing import Any

import pytest
from pydantic import ValidationError

from portfolio_optimiser.ingest import ManifestV1, load_manifest

_MANIFEST: dict[str, Any] = {
    "manifest_version": 1,
    "source": {"type": "file", "id": "prosjekt-arkiv", "root": "fixture"},
    "bundle_summary": "Cost extracts from the project archive.",
    "extractions": [
        {
            "id": "costs",
            "title": "Project costs",
            "query": "costs.csv",
            "okf_type": "dataset",
            "max_rows": 100,
        },
        {
            "id": "meta",
            "title": "Catalogue metadata",
            "query": "meta.csv",
            "okf_type": "reference",
            "max_rows": 10,
        },
    ],
}


def _write(tmp_path: Path, data: dict[str, Any], name: str = "manifest.json") -> Path:
    path = tmp_path / name
    path.write_text(json.dumps(data), encoding="utf-8")
    return path


def _variant(**overrides: Any) -> dict[str, Any]:
    data = copy.deepcopy(_MANIFEST)
    data.update(overrides)
    return data


def test_valid_file_manifest_loads_with_stamp(tmp_path: Path) -> None:
    path = _write(tmp_path, _MANIFEST)
    manifest, stamp = load_manifest(path)
    assert isinstance(manifest, ManifestV1)
    assert manifest.source.type == "file"
    assert [e.id for e in manifest.extractions] == ["costs", "meta"]
    # §5: stamp = {stem}@{first 16 hex of SHA-256 over the manifest file's RAW bytes}.
    expected = "manifest@" + hashlib.sha256(path.read_bytes()).hexdigest()[:16]
    assert stamp == expected


def test_each_missing_top_level_field_raises(tmp_path: Path) -> None:
    for field in ("manifest_version", "source", "bundle_summary", "extractions"):
        data = copy.deepcopy(_MANIFEST)
        del data[field]
        with pytest.raises(ValidationError):
            load_manifest(_write(tmp_path, data, name=f"missing-{field}.json"))


def test_manifest_version_other_than_1_rejected(tmp_path: Path) -> None:
    with pytest.raises(ValidationError):
        load_manifest(_write(tmp_path, _variant(manifest_version=2)))


def test_empty_extractions_rejected(tmp_path: Path) -> None:
    with pytest.raises(ValidationError):
        load_manifest(_write(tmp_path, _variant(extractions=[])))


def test_bad_id_grammar_rejected(tmp_path: Path) -> None:
    # §4 grammar for source.id and extraction.id: ^[a-z0-9][a-z0-9-]*$
    for bad in ("Upper", "-leading", "", "space id", "æøå"):
        data = copy.deepcopy(_MANIFEST)
        data["source"]["id"] = bad
        with pytest.raises(ValidationError):
            ManifestV1.model_validate(data)
        data = copy.deepcopy(_MANIFEST)
        data["extractions"][0]["id"] = bad
        with pytest.raises(ValidationError):
            ManifestV1.model_validate(data)


def test_duplicate_extraction_ids_rejected(tmp_path: Path) -> None:
    data = copy.deepcopy(_MANIFEST)
    data["extractions"][1]["id"] = data["extractions"][0]["id"]
    with pytest.raises(ValidationError):
        load_manifest(_write(tmp_path, data))


def test_nonpositive_max_rows_rejected(tmp_path: Path) -> None:
    for bad in (0, -1):
        data = copy.deepcopy(_MANIFEST)
        data["extractions"][0]["max_rows"] = bad
        with pytest.raises(ValidationError):
            load_manifest(_write(tmp_path, data, name=f"rows-{bad}.json"))


def test_unknown_source_type_rejected(tmp_path: Path) -> None:
    data = copy.deepcopy(_MANIFEST)
    data["source"] = {"type": "ftp", "id": "x", "root": "fixture"}
    with pytest.raises(ValidationError):
        load_manifest(_write(tmp_path, data))


def test_file_source_missing_root_rejected(tmp_path: Path) -> None:
    data = copy.deepcopy(_MANIFEST)
    del data["source"]["root"]
    with pytest.raises(ValidationError):
        load_manifest(_write(tmp_path, data))


def test_verdict_okf_type_rejected_case_insensitively(tmp_path: Path) -> None:
    # §3: the verdict layer is RESERVED — enforced at manifest validation, before any
    # source call. The manifest is otherwise fully valid, so this validator is the ONLY
    # thing standing between an ingest manifest and machine-generated "approved" verdicts.
    for spelling in ("verdict", "Verdict", "VERDICT"):
        data = copy.deepcopy(_MANIFEST)
        data["extractions"][0]["okf_type"] = spelling
        with pytest.raises(ValidationError):
            load_manifest(_write(tmp_path, data, name=f"verdict-{spelling}.json"))


def test_multiline_title_rejected(tmp_path: Path) -> None:
    for bad in ("line1\nline2", "line1\rline2", ""):
        data = copy.deepcopy(_MANIFEST)
        data["extractions"][0]["title"] = bad
        with pytest.raises(ValidationError):
            ManifestV1.model_validate(data)


def test_title_whitespace_normalized() -> None:
    # Pinned decision: title runs are collapsed at validation so the frontmatter rendering
    # (okf.render_frontmatter collapses runs) and the index label are guaranteed identical.
    data = copy.deepcopy(_MANIFEST)
    data["extractions"][0]["title"] = "  Project   costs  "
    manifest = ManifestV1.model_validate(data)
    assert manifest.extractions[0].title == "Project costs"


def test_base_url_embedded_credentials_rejected() -> None:
    # §4: base_url MUST NOT embed credentials (userinfo is the URL credential mechanism).
    data = copy.deepcopy(_MANIFEST)
    data["source"] = {"type": "http", "id": "api", "base_url": "https://user:pw@host/api"}
    with pytest.raises(ValidationError):
        ManifestV1.model_validate(data)


def test_sql_and_http_variants_validate() -> None:
    # Schema breadth (brief assumption 1): the polymorphic §4 schema validates all three
    # source variants; only the `file` connector EXECUTES in I2 (sql → I4, http → I6).
    sql = ManifestV1.model_validate(
        _variant(source={"type": "sql", "id": "db", "connection_ref": "PROJ_DB"})
    )
    assert sql.source.type == "sql"
    http = ManifestV1.model_validate(
        _variant(source={"type": "http", "id": "api", "base_url": "https://host/api"})
    )
    assert http.source.type == "http"
    assert http.source.credential_ref is None


def test_failfast_before_source_access(tmp_path: Path) -> None:
    # Ordering proof (closes key assumption 2): the manifest is malformed on max_rows AND
    # points at a root that does not exist — validation raises WITHOUT touching the root
    # (load_manifest reads only the manifest file; the ingest analogue of
    # test_no_chat_client_call_on_malformed_contract).
    data = copy.deepcopy(_MANIFEST)
    data["source"]["root"] = str(tmp_path / "does-not-exist")
    data["extractions"][0]["max_rows"] = 0
    with pytest.raises(ValidationError):
        load_manifest(_write(tmp_path, data))
    assert not (tmp_path / "does-not-exist").exists()


def test_malformed_json_raises(tmp_path: Path) -> None:
    path = tmp_path / "broken.json"
    path.write_text("{not json", encoding="utf-8")
    with pytest.raises(json.JSONDecodeError):
        load_manifest(path)