"""
Tests for FileStore

Desired behavior
----------------
- A FileStore is initialized on a directory containing files
- The FileStore reads the files and populates itself with file metadata
- If there is a FileStore.json present, its contents are read and merged with
  the file metadata
- If there are records (file_id) in the JSON metadata that are not associated
  with a file on disk anymore, they are marked as orphans with 'orphan: True'
  and added to the store.
- If there is no FileStore.json present
    - if read_only=False, the file is created
    - if read_only=True, no metadata is read in
- if read_only=False, the update() method is enabled
- if a FileStore is moved to a different location on disk (but all contents of the
  main directory are preserved), file_ids should not change and metadata should
  remain intact.
"""

import hashlib
import shutil
from datetime import datetime, timezone
from pathlib import Path

import pytest

from maggma.core import StoreError
from maggma.stores.file_store import FileStore


@pytest.fixture()
def test_dir(tmp_path):
    module_dir = Path(__file__).resolve().parent
    test_dir = module_dir / ".." / "test_files" / "file_store_test"
    shutil.copytree(str(test_dir), str(tmp_path), dirs_exist_ok=True)
    return tmp_path.resolve()


def test_record_from_file(test_dir):
    """
    Test functionality of _create_record_from_file
    """
    fs = FileStore(test_dir, read_only=True)
    fs.connect()
    f = Path(test_dir / "calculation1" / "input.in")

    relative_path = f.relative_to(test_dir)
    digest = hashlib.md5()
    digest.update(str(relative_path).encode())
    file_id = str(digest.hexdigest())

    d = fs._create_record_from_file(f)
    assert d["name"] == "input.in"
    assert d["parent"] == "calculation1"
    assert d["path"] == test_dir / "calculation1" / "input.in"
    assert d["size"] == pytest.approx(90, abs=1)
    assert isinstance(d["hash"], str)
    assert d["file_id"] == file_id
    assert d["last_updated"] == datetime.fromtimestamp(f.stat().st_mtime, tz=timezone.utc)


def test_newer_in_on_local_update(test_dir):
    """
    Init a FileStore
    modify one of the files on disk
    Init another FileStore on the same directory
    confirm that one record shows up in newer_in
    """
    fs = FileStore(test_dir, read_only=False)
    fs.connect()
    with open(test_dir / "calculation1" / "input.in", "w") as f:
        f.write("Ryan was here")
    fs2 = FileStore(test_dir, read_only=False)
    fs2.connect()

    assert fs2.last_updated > fs.last_updated
    assert (
        fs2.query_one({"path": {"$regex": "calculation1/input.in"}})["last_updated"]
        > fs.query_one({"path": {"$regex": "calculation1/input.in"}})["last_updated"]
    )
    assert len(fs.newer_in(fs2)) == 1


def test_max_depth(test_dir):
    """
    test max_depth parameter

    NOTE this test only creates a single temporary directory, meaning that
    the JSON file created by the first FileStore.init() persists for the other
    tests. This creates the possibility of orphaned metadata.
    """
    # default (None) should parse all 6 files
    fs = FileStore(test_dir, read_only=False)
    fs.connect()
    assert len(list(fs.query())) == 6

    # 0 depth should parse 1 file
    fs = FileStore(test_dir, read_only=False, max_depth=0)
    fs.connect()
    assert len(list(fs.query())) == 1

    # 1 depth should parse 5 files
    fs = FileStore(test_dir, read_only=False, max_depth=1)
    fs.connect()
    assert len(list(fs.query())) == 5

    # 2 depth should parse 6 files
    fs = FileStore(test_dir, read_only=False, max_depth=2)
    fs.connect()
    assert len(list(fs.query())) == 6


def test_orphaned_metadata(test_dir):
    """
    test behavior when orphaned metadata is found

    NOTE the design of this test exploits the fact that the test only creates
    a single temporary directory, meaning that the JSON file created by the
    first FileStore.init() persists for the other tests.
    """
    # make a FileStore of all files and add metadata to all of them
    fs = FileStore(test_dir, read_only=False)
    fs.connect()
    data = list(fs.query())
    for d in data:
        d.update({"tags": "Ryan was here"})
    fs.update(data)

    assert len(list(fs.query())) == 6
    assert len(list(fs.query({"tags": {"$exists": True}}))) == 6
    # the orphan field should be populated for all documents
    assert len(list(fs.query({"orphan": {"$exists": True}}))) == 6
    fs.close()

    # re-init the store with a different max_depth parameter
    # this will result in orphaned metadata
    # with include_orphans=True, this should be returned in queries
    fs = FileStore(test_dir, read_only=True, max_depth=1, include_orphans=True)
    with pytest.warns(UserWarning, match="Orphaned metadata was found in FileStore.json"):
        fs.connect()
    assert len(list(fs.query())) == 6
    assert len(list(fs.query({"tags": {"$exists": True}}))) == 6
    # all items, including orphans, should have a file_id and path_relative
    assert len(list(fs.query({"file_id": {"$exists": True}}))) == 6
    assert len(list(fs.query({"path_relative": {"$exists": True}}))) == 6
    assert len(list(fs.query({"orphan": True}))) == 1
    fs.close()

    # re-init the store after renaming one of the files on disk
    # this will result in orphaned metadata
    # with include_orphans=False (default), that metadata should be
    # excluded from query results
    Path(test_dir / "calculation1" / "input.in").rename(test_dir / "calculation1" / "input_renamed.in")
    fs = FileStore(test_dir, read_only=True, include_orphans=False)
    with pytest.warns(UserWarning, match="Orphaned metadata was found in FileStore.json"):
        fs.connect()
    assert len(list(fs.query())) == 6
    assert len(list(fs.query({"tags": {"$exists": True}}))) == 5
    assert len(list(fs.query({"path": {"$exists": True}}))) == 6
    # manually specifying orphan: True should still work
    assert len(list(fs.query({"orphan": True}))) == 1
    fs.close()


def test_store_files_moved(test_dir):
    """
    test behavior when the directory that constitutes the FileStore is
    moved to a new location on disk
    """
    # make a FileStore of all files and add metadata to all of them
    fs = FileStore(test_dir, read_only=False)
    fs.connect()
    data = list(fs.query())
    for d in data:
        d.update({"tags": "Ryan was here"})
    fs.update(data)

    # the orphan field should be populated for all documents, and False
    assert len(list(fs.query({"orphan": False}))) == 6
    original_file_ids = {f["file_id"] for f in fs.query()}
    original_paths = {f["path"] for f in fs.query()}
    fs.close()

    # now copy the entire FileStore to a new directory and re-initialize
    shutil.copytree(test_dir, str(test_dir / "new_store_location"), dirs_exist_ok=True)
    fs = FileStore(test_dir / "new_store_location", read_only=False)
    fs.connect()
    assert len(list(fs.query({"orphan": False}))) == 6
    assert {f["file_id"] for f in fs.query()} == original_file_ids
    # absolute paths should change to follow the FileStore
    assert {f["path"] for f in fs.query()} != original_paths
    for d in fs.query(properties=["path"]):
        assert str(d["path"]).startswith(str(fs.path))


def test_file_filters(test_dir):
    """
    Make sure multiple patterns work correctly
    """
    # here, we should get 2 input.in files and the file_2_levels_deep.json
    # the store's FileStore.json should be skipped even though .json is
    # in the file patterns
    fs = FileStore(test_dir, read_only=False, file_filters=["*.in", "*.json"])
    fs.connect()
    assert len(list(fs.query())) == 3


def test_read_only(test_dir):
    """
    Make sure nothing is written to a read-only FileStore and that
    documents cannot be deleted
    """
    with pytest.warns(UserWarning, match="JSON file 'random.json' not found"):
        fs = FileStore(test_dir, read_only=True, json_name="random.json")
        fs.connect()
    assert not Path(test_dir / "random.json").exists()
    file_id = fs.query_one()["file_id"]
    with pytest.raises(StoreError, match="read-only"):
        fs.update({"file_id": file_id, "tags": "something"})
    with pytest.raises(StoreError, match="read-only"):
        fs.remove_docs({})


def test_query(test_dir):
    """
    File contents should be read unless file is too large
    size and path keys should not be returned unless explicitly requested
    querying on 'contents' should raise a warning
    contents should be empty if a file is too large
    empty properties kwarg should return contents, size, and path (along with everything else)
    """
    fs = FileStore(test_dir, read_only=True)
    fs.connect()
    d = fs.query_one(
        {"name": "input.in", "parent": "calculation1"},
        properties=["file_id", "contents"],
    )
    assert not d.get("size")
    assert not d.get("path")
    assert d.get("file_id")
    assert d.get("contents")
    assert "This is the file named input.in" in d["contents"]

    d = fs.query_one(
        {"name": "input.in", "parent": "calculation1"},
        properties=None,
    )
    assert d.get("size")
    assert d.get("path")
    assert d.get("file_id")
    assert d.get("contents")

    with pytest.warns(UserWarning, match="'contents' is not a queryable field!"):
        fs.query_one({"contents": {"$regex": "input.in"}})

    d = fs.query_one(
        {"name": "input.in", "parent": "calculation1"},
        properties=["name", "contents"],
        contents_size_limit=50,
    )
    assert d["contents"] == "File exceeds size limit of 50 bytes"
    assert d.get("name")


def test_remove(test_dir):
    """
    Test behavior of remove_docs()
    """
    fs = FileStore(test_dir, read_only=False)
    fs.connect()
    paths = [d["path"] for d in fs.query()]
    with pytest.raises(StoreError, match="about to delete 6 items"):
        fs.remove_docs({})
    fs.remove_docs({"name": "input.in"}, confirm=True)
    assert len(list(fs.query())) == 4
    assert not Path.exists(test_dir / "calculation1" / "input.in")
    assert not Path.exists(test_dir / "calculation2" / "input.in")
    fs.remove_docs({}, confirm=True)
    assert not any(Path(p).exists() for p in paths)


def test_metadata(test_dir):
    """
    1. init a FileStore
    2. add some metadata to both 'input.in' files
    3. confirm metadata written to .json
    4. close the store, init a new one
    5. confirm metadata correctly associated with the files
    """
    fs = FileStore(test_dir, read_only=False, last_updated_field="last_change")
    fs.connect()
    query = {"name": "input.in", "parent": "calculation1"}
    key = next(iter(fs.query(query)))[fs.key]
    fs.add_metadata(
        {
            "metadata": {"experiment date": "2022-01-18"},
            fs.last_updated_field: "this should not be here",
        },
        query,
    )

    # make sure metadata has been added to the item without removing other contents
    item_from_store = next(iter(fs.query({"file_id": key})))
    assert item_from_store.get("name", False)
    assert item_from_store.get("metadata", False)
    fs.close()

    # only the updated item should have been written to the JSON,
    # and it should not contain any of the protected keys
    data = fs.metadata_store.read_json_file(fs.path / fs.json_name)
    assert len(data) == 1
    item_from_file = next(d for d in data if d["file_id"] == key)
    assert item_from_file["metadata"] == {"experiment date": "2022-01-18"}
    assert not item_from_file.get("name")
    assert not item_from_file.get("path")
    assert not item_from_file.get(fs.last_updated_field)
    assert item_from_file.get("path_relative")

    # make sure metadata is preserved after reconnecting
    fs2 = FileStore(test_dir, read_only=True)
    fs2.connect()
    data = fs2.metadata_store.read_json_file(fs2.path / fs2.json_name)
    item_from_file = next(d for d in data if d["file_id"] == key)
    assert item_from_file["metadata"] == {"experiment date": "2022-01-18"}

    # make sure reconnected store properly merges in the metadata
    item_from_store = next(iter(fs2.query({"file_id": key})))
    assert item_from_store["name"] == "input.in"
    assert item_from_store["parent"] == "calculation1"
    assert item_from_store.get("metadata") == {"experiment date": "2022-01-18"}
    fs2.close()

    # make sure reconnecting with read_only=False doesn't remove metadata from the JSON
    fs3 = FileStore(test_dir, read_only=False)
    fs3.connect()
    data = fs3.metadata_store.read_json_file(fs3.path / fs3.json_name)
    item_from_file = next(d for d in data if d["file_id"] == key)
    assert item_from_file["metadata"] == {"experiment date": "2022-01-18"}
    item_from_store = next(iter(fs3.query({"file_id": key})))
    assert item_from_store["name"] == "input.in"
    assert item_from_store["parent"] == "calculation1"
    assert item_from_store.get("metadata") == {"experiment date": "2022-01-18"}
    fs3.close()

    # test automatic metadata assignment
    def add_data_from_name(d):
        return {"calc_name": d["name"][0:5]}

    fs4 = FileStore(test_dir, read_only=False)
    fs4.connect()
    # apply the auto function to all records
    fs4.add_metadata(auto_data=add_data_from_name)
    for d in fs4.query():
        print(d)
        assert d.get("calc_name", False) == d["name"][0:5]


def test_json_name(test_dir):
    """
    Make sure custom .json name works
    """
    fs = FileStore(test_dir, read_only=False, json_name="random.json")
    fs.connect()
    assert Path(test_dir / "random.json").exists()


def test_this_dir():
    """
    Make sure connect() works when path is "."
    """
    fs = FileStore(".")
    fs.connect()
    assert not fs.name.endswith(".")


def test_encoding():
    """
    Make sure custom encoding works
    """
    fs = FileStore(".", read_only=False, encoding="utf8")
    fs.connect()
    assert Path("FileStore.json").exists()
