"""Unit tests for observation lookup index, backfill, and index sync validation."""
import sys
import os
import pytest
import datetime

sys.path.insert(0, os.path.join(os.path.dirname(__file__), '..', 'src'))
from db import StateKV
import functions
from functions import folder_observe, folder_search, forget, backfill_obs_lookup_if_needed, verify_index_sync_on_boot, KV


def make_kv(tmp_path):
    db_path = os.path.join(str(tmp_path), 'test_obs_lookup.db')
    return StateKV(db_path=db_path)


def base_payload(folder="/home/user/proj", agent="kiro", text="Test observation"):
    return {
        'folderPath': folder,
        'agentId': agent,
        'text': text,
        'timestamp': datetime.datetime.utcnow().isoformat() + 'Z',
    }


class TestObsLookupFlows:
    def test_lookup_added_on_observe(self, tmp_path):
        kv = make_kv(tmp_path)
        res = folder_observe(kv, base_payload())
        obs_id = res['observationId']

        # Verify entry in KV.obs_lookup
        lookup = kv.get(KV.obs_lookup, obs_id)
        assert lookup is not None
        assert lookup['folderPath'] == 'home/user/proj'
        assert lookup['agentId'] == 'kiro'

    def test_lookup_deleted_on_forget(self, tmp_path):
        kv = make_kv(tmp_path)
        res = folder_observe(kv, base_payload())
        obs_id = res['observationId']

        # Confirm it exists
        assert kv.get(KV.obs_lookup, obs_id) is not None

        # Delete it using forget
        forget(kv, {
            "folderPath": "/home/user/proj",
            "agentId": "kiro",
            "observationIds": [obs_id],
        })

        # Confirm it is gone from both stores
        assert kv.get(KV.obs_lookup, obs_id) is None
        assert kv.get(KV.folder_obs('home/user/proj', 'kiro'), obs_id) is None

    def test_backfill_populates_missing_lookups(self, tmp_path):
        kv = make_kv(tmp_path)

        # Ingest observations
        res1 = folder_observe(kv, base_payload(text="First"))
        res2 = folder_observe(kv, base_payload(text="Second"))
        obs1 = res1['observationId']
        obs2 = res2['observationId']

        # Manually clear the lookup index (simulating legacy data)
        kv.delete(KV.obs_lookup, obs1)
        kv.delete(KV.obs_lookup, obs2)
        assert kv.get(KV.obs_lookup, obs1) is None
        assert kv.get(KV.obs_lookup, obs2) is None

        # Run backfill
        backfill_obs_lookup_if_needed(kv)

        # Verify populated
        lookup1 = kv.get(KV.obs_lookup, obs1)
        lookup2 = kv.get(KV.obs_lookup, obs2)
        assert lookup1 is not None
        assert lookup2 is not None
        assert lookup1['folderPath'] == 'home/user/proj'
        assert lookup2['folderPath'] == 'home/user/proj'

    def test_verify_index_sync_detects_mismatch(self, tmp_path):
        kv = make_kv(tmp_path)

        # Clear indexes
        functions._bm25_index.clear()
        if functions._vector_index:
            functions._vector_index.clear()

        # Ingest one observation
        res = folder_observe(kv, base_payload())
        obs_id = res['observationId']

        # BM25 size should be 1
        assert functions._bm25_index.size == 1

        # verify_index_sync_on_boot should return True (in sync)
        assert verify_index_sync_on_boot(kv) is True

        # Manually remove from BM25 (simulate dirty restart)
        functions._bm25_index.remove(obs_id)
        assert functions._bm25_index.size == 0

        # verify_index_sync_on_boot should detect mismatch and return False
        assert verify_index_sync_on_boot(kv) is False