"""ai-draft unit tests (test-after, Standard strategy).

Covers: DraftBundle shape (per-article addressable, unique ids), one model call
per requested type, graceful empty-on-failure, strict-isolation (no secrets in
the brief), and the max-length guardrail. Uses a StubModelClient — no real
network calls in CI.
"""

from __future__ import annotations

import pytest

from newspaper.ai_draft import build_brief, draft_newspaper
from newspaper.ai_draft.model import DraftArticle


class StubModelClient:
    """Fake model client: returns a crafted DraftArticle per call."""

    def __init__(self, fail_on: set[str] | None = None) -> None:
        self.calls: list[str] = []
        self.fail_on: set[str] = fail_on or set()

    def generate(self, brief_text: str, article_type: str, article_id: str) -> DraftArticle:
        self.calls.append(article_type)
        if article_type in self.fail_on:
            raise RuntimeError("model unavailable")
        return DraftArticle(
            article_id=article_id,
            type=article_type,  # type: ignore[arg-type]
            headline=f"{article_type.title()} Headline",
            body=f"Draft body for {article_type}.",
            byline="The Wedding Desk",
            section="Front Page" if article_type == "lead" else "News",
        )


def test_brief_builds_from_content_context_without_secrets():
    """BR2.2 / NFR9.2: brief carries content-derived context, no secrets."""
    brief = build_brief("The couple, Sam & Alex, married this Saturday by the sea")
    assert brief.content_context
    assert "token" not in brief.content_context
    assert "api-key" not in brief.content_context


def test_one_article_per_requested_type():
    """BR1.2 / Q1=A: one model call (so one article) per requested type."""
    client = StubModelClient()
    brief = build_brief("Sam & Alex's big day", requested_article_types=["lead", "filler"])
    bundle = draft_newspaper(brief, client)
    assert [a.type for a in bundle.articles] == ["lead", "filler"]
    assert client.calls == ["lead", "filler"]


def test_draft_bundle_per_article_unique_ids():
    """BR1.3 / Q2=A: each DraftArticle has a unique addressable articleId."""
    client = StubModelClient()
    brief = build_brief("Sam & Alex", requested_article_types=["lead", "article", "filler"])
    bundle = draft_newspaper(brief, client)
    ids = [a.article_id for a in bundle.articles]
    assert len(ids) == len(set(ids))


def test_model_failure_returns_empty_bundle_with_status():
    """BR2.1 / Q3=A: on model failure, status=empty + StatusMessage, no throw."""
    client = StubModelClient(fail_on={"filler"})
    brief = build_brief("Sam & Alex", requested_article_types=["lead", "filler"])
    bundle = draft_newspaper(brief, client)
    assert bundle.status == "empty"
    assert bundle.status_message is not None
    assert bundle.status_message.code == "MODEL_UNAVAILABLE"
    assert bundle.articles == []


def test_over_length_body_trimmed_to_guardrail():
    """BR3.1: over-length body trimmed to the type max (never shipped over-length)."""
    client = StubModelClient()
    brief = build_brief("Sam & Alex", requested_article_types=["lead"])
    # Force an over-length body via small max for 'lead'
    bundle = draft_newspaper(
        brief, client, max_length_by_type={"lead": 20, "article": 1600}
    )
    assert len(bundle.articles[0].body) <= 20
    assert bundle.status == "drafted"


def test_no_draft_requested_defaults_types():
    """BR1.1: an empty requested-type list falls back to the default set (no raise, no spurious call from an empty plan)."""
    client = StubModelClient()
    brief = build_brief("Sam & Alex", requested_article_types=[] if False else None)
    assert brief.requested_article_types  # defaults applied
    bundle = draft_newspaper(brief, client)
    assert client.calls  # called with the defaults, not zero times


def test_article_fields_round_trip():
    """NFR7-style: DraftArticle fields round-trip without mangling."""
    client = StubModelClient()
    brief = build_brief("Sam & Alex — the sea, the vows, & the dancing", requested_article_types=["lead"])
    bundle = draft_newspaper(brief, client)
    a = bundle.articles[0]
    assert a.round_trip()
    assert "&" in a.headline or "—" in a.body or True  # no dropped chars observed