"""Unit tests for src/my_deepagent/persona.py."""

from __future__ import annotations

import re
from pathlib import Path

import pytest
from pydantic import ValidationError

from my_deepagent.enums import Backend
from my_deepagent.persona import (
    FilesystemPermissionSpec,
    Persona,
    PersonaSubagent,
    load_persona_yaml,
    load_personas_from_dir,
)

# ---------------------------------------------------------------------------
# Helpers
# ---------------------------------------------------------------------------

PERSONAS_DIR = Path(__file__).parent.parent.parent / "docs" / "schemas" / "personas"


def _minimal_persona_dict(**overrides: object) -> dict[str, object]:
    """Return a minimal valid persona dict, overridable per-test."""
    base: dict[str, object] = {
        "name": "test-persona",
        "version": 1,
        "backend": "openrouter",
        "model": "openrouter:anthropic/claude-sonnet-4-6",
        "provider_origin": "US/Anthropic",
        "capabilities": ["spec_write"],
        "max_risk_level": "low",
        "system_prompt": "You are a test persona for unit tests.",
    }
    base.update(overrides)
    return base


# ---------------------------------------------------------------------------
# Seed yaml: all 10 load successfully
# ---------------------------------------------------------------------------


def test_all_seed_personas_load() -> None:
    personas = load_personas_from_dir(PERSONAS_DIR)
    assert len(personas) == 10


def test_seed_persona_names_unique() -> None:
    personas = load_personas_from_dir(PERSONAS_DIR)
    keys = [(p.name, p.version) for p in personas]
    assert len(keys) == len(set(keys))


def test_seed_personas_backends_are_openrouter() -> None:
    personas = load_personas_from_dir(PERSONAS_DIR)
    for p in personas:
        assert p.backend == Backend.OPENROUTER


def test_seed_persona_capabilities_non_empty() -> None:
    personas = load_personas_from_dir(PERSONAS_DIR)
    for p in personas:
        assert len(p.capabilities) >= 1


def test_seed_persona_hash_is_64_char_hex() -> None:
    personas = load_personas_from_dir(PERSONAS_DIR)
    for p in personas:
        h = p.compute_hash()
        assert re.fullmatch(r"[0-9a-f]{64}", h), f"{p.name}: bad hash {h!r}"


def test_seed_persona_frozen() -> None:
    """Frozen model: attribute assignment must raise."""
    personas = load_personas_from_dir(PERSONAS_DIR)
    p = personas[0]
    with pytest.raises((TypeError, ValidationError)):
        p.name = "mutated"  # type: ignore[misc]


# ---------------------------------------------------------------------------
# extra="forbid": unknown fields rejected
# ---------------------------------------------------------------------------


def test_persona_extra_field_raises() -> None:
    data = _minimal_persona_dict(unknown_field="surprise")
    with pytest.raises(ValidationError, match="extra"):
        Persona.model_validate(data)


# ---------------------------------------------------------------------------
# FilesystemPermissionSpec validators
# ---------------------------------------------------------------------------


def test_permission_path_no_leading_slash_raises() -> None:
    with pytest.raises(ValidationError, match="must start with '/'"):
        FilesystemPermissionSpec(operations=["read"], paths=["relative/path"])


def test_permission_path_dotdot_raises() -> None:
    with pytest.raises(ValidationError, match=r"must not contain '\.\.'"):
        FilesystemPermissionSpec(operations=["read"], paths=["/foo/../bar"])


def test_permission_path_tilde_raises() -> None:
    with pytest.raises(ValidationError, match="must not contain '~'"):
        FilesystemPermissionSpec(operations=["read"], paths=["/path/~expansion/secret"])


def test_permission_path_glob_ok() -> None:
    """Glob patterns like /** should not trigger the path validator."""
    spec = FilesystemPermissionSpec(operations=["read", "write"], paths=["/**"])
    assert spec.paths == ("/**",)


def test_permission_mode_default_allow() -> None:
    spec = FilesystemPermissionSpec(operations=["read"], paths=["/tmp"])
    assert spec.mode == "allow"


def test_permission_deny_mode() -> None:
    spec = FilesystemPermissionSpec(operations=["write"], paths=["/.env"], mode="deny")
    assert spec.mode == "deny"


def test_permission_extra_field_raises() -> None:
    with pytest.raises(ValidationError):
        FilesystemPermissionSpec(operations=["read"], paths=["/tmp"], unknown=True)  # type: ignore[call-arg]


# ---------------------------------------------------------------------------
# Persona.compute_hash: determinism
# ---------------------------------------------------------------------------


def test_compute_hash_deterministic() -> None:
    p = Persona.model_validate(_minimal_persona_dict())
    hashes = [p.compute_hash() for _ in range(20)]
    assert len(set(hashes)) == 1


def test_compute_hash_different_personas_differ() -> None:
    p1 = Persona.model_validate(_minimal_persona_dict(name="p1"))
    p2 = Persona.model_validate(_minimal_persona_dict(name="p2"))
    assert p1.compute_hash() != p2.compute_hash()


def test_compute_hash_version_affects_hash() -> None:
    p1 = Persona.model_validate(_minimal_persona_dict(version=1))
    p2 = Persona.model_validate(_minimal_persona_dict(version=2))
    assert p1.compute_hash() != p2.compute_hash()


# ---------------------------------------------------------------------------
# Persona: min_length, ge validators
# ---------------------------------------------------------------------------


def test_persona_empty_capabilities_raises() -> None:
    data = _minimal_persona_dict(capabilities=[])
    with pytest.raises(ValidationError):
        Persona.model_validate(data)


def test_persona_version_zero_raises() -> None:
    data = _minimal_persona_dict(version=0)
    with pytest.raises(ValidationError):
        Persona.model_validate(data)


def test_persona_negative_max_cost_raises() -> None:
    data = _minimal_persona_dict(max_cost_per_call_usd=-0.01)
    with pytest.raises(ValidationError):
        Persona.model_validate(data)


def test_persona_system_prompt_too_short_raises() -> None:
    data = _minimal_persona_dict(system_prompt="short")
    with pytest.raises(ValidationError):
        Persona.model_validate(data)


# ---------------------------------------------------------------------------
# load_persona_yaml: file not found
# ---------------------------------------------------------------------------


def test_load_persona_yaml_missing_file(tmp_path: Path) -> None:
    with pytest.raises(FileNotFoundError):
        load_persona_yaml(tmp_path / "nonexistent.yaml")


# ---------------------------------------------------------------------------
# load_personas_from_dir: duplicate detection
# ---------------------------------------------------------------------------


def test_load_personas_from_dir_duplicate_raises(tmp_path: Path) -> None:
    import yaml

    data = _minimal_persona_dict()
    for fname in ("persona-a@1.yaml", "persona-b@1.yaml"):
        (tmp_path / fname).write_text(yaml.dump(data), encoding="utf-8")

    with pytest.raises(ValueError, match="duplicate persona"):
        load_personas_from_dir(tmp_path)


def test_load_personas_from_dir_missing_dir() -> None:
    result = load_personas_from_dir(Path("/nonexistent_directory_xyz"))
    assert result == []


def test_load_personas_from_dir_sorted_by_filename(tmp_path: Path) -> None:
    """Files are loaded in filename order for determinism."""
    import yaml

    for i, name in enumerate(["zz-persona", "aa-persona"]):
        data = _minimal_persona_dict(name=name, version=1)
        (tmp_path / f"{name}@1.yaml").write_text(yaml.dump(data), encoding="utf-8")

    personas = load_personas_from_dir(tmp_path)
    assert personas[0].name == "aa-persona"
    assert personas[1].name == "zz-persona"


# ---------------------------------------------------------------------------
# PersonaSubagent: extra="forbid", min_length
# ---------------------------------------------------------------------------


def test_subagent_extra_field_raises() -> None:
    with pytest.raises(ValidationError):
        PersonaSubagent(
            name="x",
            description="at least ten chars here",
            system_prompt="at least ten chars here",
            unknown_field=True,  # type: ignore[call-arg]
        )


def test_subagent_short_description_raises() -> None:
    with pytest.raises(ValidationError):
        PersonaSubagent(name="x", description="short", system_prompt="at least ten chars here")


# ---------------------------------------------------------------------------
# Snapshot: specific persona hashes are stable
# ---------------------------------------------------------------------------


def test_default_interactive_hash_prefix() -> None:
    """Hash of default-interactive@1 must start with 8193103c.

    Hash updated: permissions block removed from yaml (deepagents 0.6.1 workaround).
    """
    personas = load_personas_from_dir(PERSONAS_DIR)
    p = next(q for q in personas if q.name == "default-interactive")
    assert p.compute_hash().startswith("8193103c")


def test_spec_writer_hash_prefix() -> None:
    """Hash of openrouter-claude-spec-writer@1 must be stable."""
    personas = load_personas_from_dir(PERSONAS_DIR)
    p = next(q for q in personas if q.name == "openrouter-claude-spec-writer")
    h = p.compute_hash()
    assert len(h) == 64
    assert re.fullmatch(r"[0-9a-f]{64}", h)


# ---------------------------------------------------------------------------
# Step 2 patch: null byte path rejection
# ---------------------------------------------------------------------------


def test_filesystem_permission_null_byte_rejected() -> None:
    """Null bytes in a filesystem permission path must be rejected."""
    with pytest.raises(ValidationError, match="null bytes"):
        FilesystemPermissionSpec.model_validate(
            {
                "operations": ["read"],
                "paths": ["/foo\x00/bar"],
                "mode": "deny",
            }
        )


# ---------------------------------------------------------------------------
# Deep immutability: nested list-valued fields are tuples (cannot be mutated)
# ---------------------------------------------------------------------------


def test_persona_capabilities_immutable() -> None:
    """capabilities is a tuple — .append() must raise AttributeError."""
    p = Persona.model_validate(_minimal_persona_dict())
    with pytest.raises((AttributeError, TypeError)):
        p.capabilities.append(None)  # type: ignore[attr-defined]


def test_persona_subagents_immutable() -> None:
    """subagents is a tuple — .append() must raise AttributeError."""
    p = Persona.model_validate(_minimal_persona_dict())
    with pytest.raises((AttributeError, TypeError)):
        p.subagents.append(None)  # type: ignore[attr-defined]


def test_persona_skills_immutable() -> None:
    """skills is a tuple — .append() must raise AttributeError."""
    p = Persona.model_validate(_minimal_persona_dict())
    with pytest.raises((AttributeError, TypeError)):
        p.skills.append("new_skill")  # type: ignore[attr-defined]


def test_filesystem_permission_paths_immutable() -> None:
    """paths is a tuple — .append() must raise AttributeError."""
    perm = FilesystemPermissionSpec(operations=("read",), paths=("/foo",), mode="allow")
    with pytest.raises((AttributeError, TypeError)):
        perm.paths.append("/bar")  # type: ignore[attr-defined]


def test_filesystem_permission_operations_immutable() -> None:
    """operations is a tuple — .append() must raise AttributeError."""
    perm = FilesystemPermissionSpec(operations=("read",), paths=("/foo",), mode="allow")
    with pytest.raises((AttributeError, TypeError)):
        perm.operations.append("write")  # type: ignore[attr-defined]