from __future__ import annotations

from datetime import timedelta

from agent_gitea.config import LabelsConfig
from agent_gitea.models import TaskState, dt_to_db, utcnow
from agent_gitea.scanner import is_issue_eligible, scan_eligible_issues
from agent_gitea.state import validate_transition


def test_issue_eligibility_filters_required_and_blocking_labels(db):
    repo = db.upsert_repository(owner="acme", name="service", clone_url="x", default_branch="main", enabled=True)
    issue = db.upsert_issue(
        repo_id=repo.id,
        issue_number=1,
        title="Fix",
        body="",
        labels=["agent:ready"],
        state="open",
        html_url="url",
    )
    assert is_issue_eligible(issue, LabelsConfig())

    blocked = db.upsert_issue(
        repo_id=repo.id,
        issue_number=2,
        title="Risk",
        body="",
        labels=["agent:ready", "risk:high"],
        state="open",
        html_url="url",
    )
    assert not is_issue_eligible(blocked, LabelsConfig())


def test_scan_creates_task_unless_active_task_exists(db):
    repo = db.upsert_repository(owner="acme", name="service", clone_url="x", default_branch="main", enabled=True)
    db.upsert_issue(
        repo_id=repo.id,
        issue_number=1,
        title="Fix",
        body="",
        labels=["agent:ready"],
        state="open",
        html_url="url",
    )

    first = scan_eligible_issues(db, LabelsConfig())
    second = scan_eligible_issues(db, LabelsConfig())

    assert len(first) == 1
    assert second == []


def test_scan_ignores_repositories_not_allowed_by_current_config(db):
    repo = db.upsert_repository(owner="acme", name="old", clone_url="x", default_branch="main", enabled=True)
    db.upsert_issue(
        repo_id=repo.id,
        issue_number=1,
        title="Fix",
        body="",
        labels=["agent:ready"],
        state="open",
        html_url="url",
    )

    created = scan_eligible_issues(db, LabelsConfig(), allowed_repositories={"acme/new"})

    assert created == []


def test_terminal_task_does_not_create_scan_loop(db):
    repo = db.upsert_repository(owner="acme", name="service", clone_url="x", default_branch="main", enabled=True)
    db.upsert_issue(
        repo_id=repo.id,
        issue_number=1,
        title="Fix",
        body="",
        labels=["agent:ready"],
        state="open",
        html_url="url",
    )
    [task_id] = scan_eligible_issues(db, LabelsConfig())
    db.transition(task_id, TaskState.CLAIMED)
    db.transition(task_id, TaskState.PLANNING)
    db.transition(task_id, TaskState.IMPLEMENTING)
    db.transition(task_id, TaskState.BLOCKED, clear_lease=True)

    created = scan_eligible_issues(db, LabelsConfig())

    assert created == []


def test_claim_next_task_claims_expired_lease(db):
    repo = db.upsert_repository(owner="acme", name="service", clone_url="x", default_branch="main", enabled=True)
    task = db.create_task(repo.id, 1)
    claimed = db.claim_next_task("worker-a", 60)
    assert claimed is not None
    assert claimed.state == TaskState.CLAIMED

    db.conn.execute(
        "UPDATE tasks SET state = ?, lease_expires_at = ? WHERE id = ?",
        (TaskState.IMPLEMENTING.value, dt_to_db(utcnow() - timedelta(seconds=10)), task.id),
    )
    db.conn.commit()

    reclaimed = db.claim_next_task("worker-b", 60)
    assert reclaimed is not None
    assert reclaimed.id == task.id
    assert reclaimed.lease_owner == "worker-b"


def test_retry_task_clears_active_lease(db):
    repo = db.upsert_repository(owner="acme", name="service", clone_url="x", default_branch="main", enabled=True)
    task = db.create_task(repo.id, 1)
    claimed = db.claim_next_task("worker-a", 60)
    assert claimed is not None
    db.transition(claimed.id, TaskState.PLANNING, error_message="stuck")

    retried = db.retry_task(task.id)

    assert retried.state == TaskState.DISCOVERED
    assert retried.lease_owner is None
    assert retried.lease_expires_at is None
    assert retried.error_message is None


def test_state_transition_validation():
    validate_transition(TaskState.DISCOVERED, TaskState.CLAIMED)

    try:
        validate_transition(TaskState.DISCOVERED, TaskState.PR_OPENED)
    except ValueError as exc:
        assert "DISCOVERED -> PR_OPENED" in str(exc)
    else:
        raise AssertionError("expected invalid transition")