import json
import logging
import os
import pprint
import shutil
from typing import Any, Callable, Dict, List, Optional, Tuple, Union

import deepdiff

from tests.test_helpers.type_helpers import PytestConfig

logger = logging.getLogger(__name__)

IGNORE_PATH_TIMESTAMPS = [
    # Ignore timestamps from the ETL pipeline. A couple examples:
    # root[0]['proposedSnapshot']['com.linkedin.pegasus2avro.metadata.snapshot.DatasetSnapshot']['aspects'][0]['com.linkedin.pegasus2avro.common.Ownership']['lastModified']['time']
    # root[69]['proposedSnapshot']['com.linkedin.pegasus2avro.metadata.snapshot.DatasetSnapshot']['aspects'][0]['com.linkedin.pegasus2avro.schema.SchemaMetadata']['lastModified']['time']"
    # root[0]['proposedSnapshot']['com.linkedin.pegasus2avro.metadata.snapshot.DatasetSnapshot']['aspects'][1]['com.linkedin.pegasus2avro.dataset.UpstreamLineage']['upstreams'][0]['auditStamp']['time']
    r"root\[\d+\]\['proposedSnapshot'\].+\['aspects'\].+\['created'\]\['time'\]",
    r"root\[\d+\]\['proposedSnapshot'\].+\['aspects'\].+\['lastModified'\]\['time'\]",
    r"root\[\d+\]\['proposedSnapshot'\].+\['aspects'\].+\['createStamp'\]\['time'\]",
    r"root\[\d+\]\['proposedSnapshot'\].+\['aspects'\].+\['auditStamp'\]\['time'\]",
]


class MCEConstants:
    PROPOSED_SNAPSHOT = "proposedSnapshot"
    DATASET_SNAPSHOT_CLASS = (
        "com.linkedin.pegasus2avro.metadata.snapshot.DatasetSnapshot"
    )


class MCPConstants:
    CHANGE_TYPE = "changeType"
    ENTITY_URN = "entityUrn"
    ENTITY_TYPE = "entityType"
    ASPECT_NAME = "aspectName"
    ASPECT_VALUE = "aspect"


class EntityType:
    DATASET = "dataset"
    PIPELINE = "dataFlow"
    FLOW = "dataFlow"
    TASK = "dataJob"
    JOB = "dataJob"
    USER = "corpuser"
    GROUP = "corpGroup"


def load_json_file(filename: Union[str, os.PathLike]) -> object:
    with open(str(filename)) as f:
        a = json.load(f)
    return a


def clean_nones(value):
    """
    Recursively remove all None values from dictionaries and lists, and returns
    the result as a new dictionary or list.
    """
    if isinstance(value, list):
        return [clean_nones(x) for x in value if x is not None]
    elif isinstance(value, dict):
        return {key: clean_nones(val) for key, val in value.items() if val is not None}
    else:
        return value


def assert_mces_equal(
    output: object, golden: object, ignore_paths: Optional[List[str]] = None
) -> None:
    # This method assumes we're given a list of MCE json objects.
    diff = deepdiff.DeepDiff(
        golden, output, exclude_regex_paths=ignore_paths, ignore_order=True
    )
    if diff:
        # Attempt a clean diff (removing None-s)
        assert isinstance(output, list)
        assert isinstance(golden, list)
        clean_output = [clean_nones(o) for o in output]
        clean_golden = [clean_nones(g) for g in golden]
        clean_diff = deepdiff.DeepDiff(
            clean_golden,
            clean_output,
            exclude_regex_paths=ignore_paths,
            ignore_order=True,
        )
        if clean_diff != diff:
            logger.warning(
                f"MCE-s differ, clean MCE-s are fine\n{pprint.pformat(diff)}"
            )
        diff = clean_diff

    assert (
        not diff
    ), f"MCEs differ\n{pprint.pformat(diff)} \n output was: {json.dumps(output)}"


def check_golden_file(
    pytestconfig: PytestConfig,
    output_path: Union[str, os.PathLike],
    golden_path: Union[str, os.PathLike],
    ignore_paths: Optional[List[str]] = None,
) -> None:

    update_golden = pytestconfig.getoption("--update-golden-files")
    golden_exists = os.path.isfile(golden_path)

    if not update_golden and not golden_exists:
        raise FileNotFoundError(
            "Golden file does not exist. Please run with the --update-golden-files option to create."
        )

    output = load_json_file(output_path)

    # if updating a golden file that doesn't exist yet, load the output again
    if update_golden and not golden_exists:
        golden = load_json_file(output_path)
        shutil.copyfile(str(output_path), str(golden_path))
    else:
        golden = load_json_file(golden_path)

    try:
        assert_mces_equal(output, golden, ignore_paths)

    except AssertionError as e:
        # only update golden files if the diffs are not empty
        if update_golden:
            shutil.copyfile(str(output_path), str(golden_path))

        # raise the error if we're just running the test
        else:
            raise e


def _get_field_for_entity_type_in_mce(entity_type: str) -> str:
    """Returns the field to look for depending on the type of entity in the MCE"""
    if entity_type == EntityType.DATASET:
        return MCEConstants.DATASET_SNAPSHOT_CLASS
    raise Exception(f"Not implemented for entity_type {entity_type}")


def _get_filter(
    mce: bool = False, mcp: bool = False, entity_type: Optional[str] = None
) -> Callable[[Dict], bool]:
    if mce:
        # cheap way to determine if we are working with an MCE for the appropriate entity_type
        if entity_type:
            return (
                lambda x: MCEConstants.PROPOSED_SNAPSHOT in x
                and _get_field_for_entity_type_in_mce(str(entity_type))
                in x[MCEConstants.PROPOSED_SNAPSHOT]
            )
        else:
            return lambda x: MCEConstants.PROPOSED_SNAPSHOT in x
    if mcp:
        # cheap way to determine if we are working with an MCP
        return lambda x: MCPConstants.CHANGE_TYPE in x and (
            x[MCPConstants.ENTITY_TYPE] == entity_type if entity_type else True
        )
    return lambda _: False


def _get_element(event: Dict[str, Any], path_spec: List[str]) -> Any:
    try:
        for p in path_spec:
            event = event.get(p, {})
            if not event:
                return None
        return event
    except Exception as e:
        print(event)
        raise e


def _element_matches_pattern(
    event: Dict[str, Any], path_spec: List[str], pattern: str
) -> Tuple[bool, bool]:
    import re

    element = _get_element(event, path_spec)
    if element is None:
        return (False, False)
    else:
        return (True, re.search(pattern, str(element)) is not None)


def assert_mcp_entity_urn(
    filter: str, entity_type: str, regex_pattern: str, file: str
) -> int:
    def get_path_spec_for_urn() -> List[str]:
        return [MCPConstants.ENTITY_URN]

    test_output = load_json_file(file)
    if isinstance(test_output, list):
        path_spec = get_path_spec_for_urn()
        filter_operator = _get_filter(mcp=True, entity_type=entity_type)
        filtered_events = [
            (x, _element_matches_pattern(x, path_spec, regex_pattern))
            for x in test_output
            if filter_operator(x)
        ]
        failed_events = [y for y in filtered_events if not y[1][0] or not y[1][1]]
        if failed_events:
            raise Exception("Failed to match events", failed_events)
        return len(filtered_events)
    else:
        raise Exception(
            f"Did not expect the file {file} to not contain a list of items"
        )


def _get_mce_urn_path_spec(entity_type: str) -> List[str]:
    if entity_type == EntityType.DATASET:
        return [
            MCEConstants.PROPOSED_SNAPSHOT,
            MCEConstants.DATASET_SNAPSHOT_CLASS,
            "urn",
        ]
    raise Exception(f"Not implemented for entity_type: {entity_type}")


def _get_mcp_urn_path_spec() -> List[str]:
    return [MCPConstants.ENTITY_URN]


def assert_mce_entity_urn(
    filter: str, entity_type: str, regex_pattern: str, file: str
) -> int:

    test_output = load_json_file(file)
    if isinstance(test_output, list):
        path_spec = _get_mce_urn_path_spec(entity_type)
        filter_operator = _get_filter(mce=True)
        filtered_events = [
            (x, _element_matches_pattern(x, path_spec, regex_pattern))
            for x in test_output
            if filter_operator(x)
        ]
        failed_events = [y for y in filtered_events if not y[1][0] or not y[1][1]]
        if failed_events:
            raise Exception(
                "Failed to match events: {json.dumps(failed_events, indent=2)}"
            )
        return len(filtered_events)
    else:
        raise Exception(
            f"Did not expect the file {file} to not contain a list of items"
        )


def assert_for_each_entity(
    entity_type: str, aspect_name: str, aspect_field_matcher: Dict[str, str], file: str
) -> int:
    """Assert that an aspect name with the desired fields exists for each entity urn"""
    test_output = load_json_file(file)
    assert isinstance(test_output, list)
    # mce urns
    mce_urns = set(
        [
            _get_element(x, _get_mce_urn_path_spec(entity_type))
            for x in test_output
            if _get_filter(mce=True, entity_type=entity_type)(x)
        ]
    )
    mcp_urns = set(
        [
            _get_element(x, _get_mcp_urn_path_spec())
            for x in test_output
            if _get_filter(mcp=True, entity_type=entity_type)(x)
        ]
    )
    all_urns = mce_urns.union(mcp_urns)
    # there should not be any None urns
    assert None not in all_urns
    aspect_map = {urn: None for urn in all_urns}
    # iterate over all mcps
    for o in [
        mcp
        for mcp in test_output
        if _get_filter(mcp=True, entity_type=entity_type)(mcp)
    ]:
        if o.get(MCPConstants.ASPECT_NAME) == aspect_name:
            # load the inner aspect payload and assign to this urn
            aspect_map[o[MCPConstants.ENTITY_URN]] = json.loads(
                o.get(MCPConstants.ASPECT_VALUE, {}).get("value")
            )

    success: List[str] = []
    failures: List[str] = []
    for urn, aspect_val in aspect_map.items():
        if aspect_val is not None:
            for f in aspect_field_matcher:
                assert aspect_field_matcher[f] == _get_element(
                    aspect_val, [f]
                ), f"urn: {urn} -> Field {f} must match value {aspect_field_matcher[f]}, found {_get_element(aspect_val, [f])}"
            success.append(urn)
        else:
            print(f"Adding {urn} to failures")
            failures.append(urn)

    if success:
        print(f"Succeeded on assertion for urns {success}")
    if failures:
        assert (
            False
        ), f"Failed to find aspect_name {aspect_name} for urns {json.dumps(failures, indent=2)}"

    return len(success)