import shutil
import uuid
from pathlib import Path
import pytest
from api.services import forge_projection as fp
from api.services import historical_projection as hp
from tests.test_forge_projection import _FakeSession,_Repo,_Row,_TaskRow

FIXTURE=Path(__file__).parent/'fixtures/railiance-cluster'
@pytest.fixture
def bound(tmp_path):
    root=tmp_path/'railiance-cluster';shutil.copytree(FIXTURE,root)
    derived=fp.derive_from_checkout(root,'railiance-cluster','candidate')
    assert len(derived.workplans)==3
    rows=[];tasks=[]
    for parent in derived.workplans:
        row=_Row(parent.record_id.lower(),'finished',parent.relative_path);row.id=uuid.UUID(parent.uuid);rows.append(row)
        for source in parent.tasks:
            task=_TaskRow(source.record_id,status='done',workplan_id=row.id);task.id=uuid.UUID(source.uuid);tasks.append(task)
    assert len(tasks)==15
    return root,derived,rows,tasks

def test_exact_three_sources_derive_only_frozen_15_task_uuids(bound):
    root,derived,rows,tasks=bound
    assert all(parent.historical_preservation for parent in derived.workplans)
    assert all(parent.uuid!=fp.derived_record_uuid(parent.record_id) for parent in derived.workplans)
    expected={item['uuid'] for entry in hp.BINDINGS if entry['repo']=='railiance-cluster' for item in entry['tasks']}
    assert {str(t.id) for t in tasks}==expected

@pytest.mark.asyncio
async def test_existing_rows_are_entirely_unchanged_on_normal_receiving(bound):
    root,derived,rows,tasks=bound;before=[dict(x.__dict__) for x in rows+tasks]
    session=_FakeSession(_Repo(),rows,task_rows=tasks)
    outcome=await fp.reset_repository_projection(session,'railiance-cluster',derived=derived)
    assert outcome.status=='noop' and not outcome.refused
    assert [dict(x.__dict__) for x in rows+tasks]==before
    assert not session.added and not session.deleted

@pytest.mark.parametrize('defect',['missing-parent','missing-task','foreign-holder','nonterminal-task','nonterminal-parent','duplicate-current-label'])
@pytest.mark.asyncio
async def test_unsupported_actual_binding_refuses_before_any_mutation(bound,defect):
    root,derived,rows,tasks=bound
    if defect=='missing-parent':rows.pop()
    elif defect=='missing-task':tasks.pop()
    elif defect=='foreign-holder':tasks[0].workplan_id=uuid.uuid4()
    elif defect=='nonterminal-task':tasks[0].status='progress'
    elif defect=='duplicate-current-label':tasks.append(_TaskRow(tasks[0].record_id,status='done',workplan_id=tasks[0].workplan_id))
    else:rows[0].status='active'
    before=[dict(x.__dict__) for x in rows+tasks];session=_FakeSession(_Repo(),rows,task_rows=tasks)
    outcome=await fp.reset_repository_projection(session,'railiance-cluster',derived=derived)
    assert outcome.status=='refused';assert [dict(x.__dict__) for x in rows+tasks]==before
    assert not session.added and not session.deleted

@pytest.mark.parametrize('change',['hash-drift','missing','symlink','live-source','missing-source-uuid'])
def test_frozen_source_drift_refuses_derivation(bound,change):
    root,*_=bound;p=next((root/'workplans/archived').glob('*.md'));raw=p.read_bytes()
    if change=='missing':p.unlink()
    elif change=='symlink':p.unlink();target=root/'saved';target.write_bytes(raw);p.symlink_to(target)
    elif change=='live-source':p.write_bytes(raw.replace(b'status: finished',b'status: active',1))
    elif change=='missing-source-uuid':p.write_bytes(raw.replace(b'state_hub_task_id:',b'old_task_id:',1))
    else:p.write_bytes(raw+b'\nunreviewed\n')
    with pytest.raises(fp.ForgeDeriveError,match='Historical source binding'):fp.derive_from_checkout(root,'railiance-cluster','candidate')

def test_unknown_repository_never_trusts_frozen_source_uuids(bound):
    root,derived,*_=bound;other=fp.derive_from_checkout(root,'different-repo','candidate')
    assert not any(parent.historical_preservation for parent in other.workplans)
    assert not {parent.uuid for parent in derived.workplans}&{parent.uuid for parent in other.workplans}