# It's possible to run any regular test with the local fs remote storage via
# env NEON_PAGESERVER_OVERRIDES="remote_storage={local_path='/tmp/neon_zzz/'}" poetry ......

import os
import shutil
import time
from pathlib import Path

import pytest
from fixtures.log_helper import log
from fixtures.neon_fixtures import (
    NeonEnvBuilder,
    RemoteStorageKind,
    assert_no_in_progress_downloads_for_tenant,
    available_remote_storages,
    wait_for_last_record_lsn,
    wait_for_upload,
)
from fixtures.types import Lsn, TenantId, TimelineId
from fixtures.utils import query_scalar, wait_until


#
# Tests that a piece of data is backed up and restored correctly:
#
# 1. Initial pageserver
#   * starts a pageserver with remote storage, stores specific data in its tables
#   * triggers a checkpoint (which produces a local data scheduled for backup), gets the corresponding timeline id
#   * polls the timeline status to ensure it's copied remotely
#   * inserts more data in the pageserver and repeats the process, to check multiple checkpoints case
#   * stops the pageserver, clears all local directories
#
# 2. Second pageserver
#   * starts another pageserver, connected to the same remote storage
#   * timeline_attach is called for the same timeline id
#   * timeline status is polled until it's downloaded
#   * queries the specific data, ensuring that it matches the one stored before
#
# The tests are done for all types of remote storage pageserver supports.
@pytest.mark.parametrize("remote_storage_kind", available_remote_storages())
def test_remote_storage_backup_and_restore(
    neon_env_builder: NeonEnvBuilder,
    remote_storage_kind: RemoteStorageKind,
):
    # Use this test to check more realistic SK ids: some etcd key parsing bugs were related,
    # and this test needs SK to write data to pageserver, so it will be visible
    neon_env_builder.safekeepers_id_start = 12

    neon_env_builder.enable_remote_storage(
        remote_storage_kind=remote_storage_kind,
        test_name="test_remote_storage_backup_and_restore",
    )

    data_id = 1
    data_secret = "very secret secret"

    ##### First start, insert secret data and upload it to the remote storage
    env = neon_env_builder.init_start()

    # FIXME: Is this expected?
    env.pageserver.allowed_errors.append(
        ".*marking .* as locally complete, while it doesnt exist in remote index.*"
    )
    env.pageserver.allowed_errors.append(".*No timelines to attach received.*")

    env.pageserver.allowed_errors.append(".*Tenant download is already in progress.*")
    env.pageserver.allowed_errors.append(".*Failed to get local tenant state.*")
    env.pageserver.allowed_errors.append(".*No metadata file found in the timeline directory.*")

    pageserver_http = env.pageserver.http_client()
    pg = env.postgres.create_start("main")

    client = env.pageserver.http_client()

    tenant_id = TenantId(pg.safe_psql("show neon.tenant_id")[0][0])
    timeline_id = TimelineId(pg.safe_psql("show neon.timeline_id")[0][0])

    checkpoint_numbers = range(1, 3)

    for checkpoint_number in checkpoint_numbers:
        with pg.cursor() as cur:
            cur.execute(
                f"""
                CREATE TABLE t{checkpoint_number}(id int primary key, secret text);
                INSERT INTO t{checkpoint_number} VALUES ({data_id}, '{data_secret}|{checkpoint_number}');
            """
            )
            current_lsn = Lsn(query_scalar(cur, "SELECT pg_current_wal_flush_lsn()"))

        # wait until pageserver receives that data
        wait_for_last_record_lsn(client, tenant_id, timeline_id, current_lsn)

        # run checkpoint manually to be sure that data landed in remote storage
        pageserver_http.timeline_checkpoint(tenant_id, timeline_id)

        log.info(f"waiting for checkpoint {checkpoint_number} upload")
        # wait until pageserver successfully uploaded a checkpoint to remote storage
        wait_for_upload(client, tenant_id, timeline_id, current_lsn)
        log.info(f"upload of checkpoint {checkpoint_number} is done")

    ##### Stop the first pageserver instance, erase all its data
    env.postgres.stop_all()
    env.pageserver.stop()

    dir_to_clear = Path(env.repo_dir) / "tenants"
    shutil.rmtree(dir_to_clear)
    os.mkdir(dir_to_clear)

    ##### Second start, restore the data and ensure it's the same
    env.pageserver.start()

    # Introduce failpoint in download
    pageserver_http.configure_failpoints(("remote-storage-download-pre-rename", "return"))

    client.tenant_attach(tenant_id)

    # is there a better way to assert that failpoint triggered?
    time.sleep(10)

    # assert cannot attach timeline that is scheduled for download
    with pytest.raises(Exception, match="Conflict: Tenant download is already in progress"):
        client.tenant_attach(tenant_id)

    tenant_status = client.tenant_status(tenant_id)
    log.info("Tenant status with active failpoint: %s", tenant_status)
    assert tenant_status["has_in_progress_downloads"] is True

    # trigger temporary download files removal
    env.pageserver.stop()
    env.pageserver.start()

    client.tenant_attach(tenant_id)

    log.info("waiting for timeline redownload")
    wait_until(
        number_of_iterations=20,
        interval=1,
        func=lambda: assert_no_in_progress_downloads_for_tenant(client, tenant_id),
    )

    detail = client.timeline_detail(tenant_id, timeline_id)
    log.info("Timeline detail after attach completed: %s", detail)
    assert (
        Lsn(detail["last_record_lsn"]) >= current_lsn
    ), "current db Lsn should should not be less than the one stored on remote storage"
    assert not detail["awaits_download"]

    pg = env.postgres.create_start("main")
    with pg.cursor() as cur:
        for checkpoint_number in checkpoint_numbers:
            assert (
                query_scalar(cur, f"SELECT secret FROM t{checkpoint_number} WHERE id = {data_id};")
                == f"{data_secret}|{checkpoint_number}"
            )