import dataclasses
import datetime
import enum
import re
import typing
import uuid

import marshmallow_dataclass
from marshmallow import post_load
from marshmallow import pre_load

from . import SchemaBase
from .algorithms import ExecutionScript
from .path import Path
from .results import EmptyResults
from .results import JsonResults
from .results import LocalResults
from .results import RasterResults
from .results import TimeSeriesTableResult


class ScriptStatus(enum.Enum):
    SUCCESS = "SUCCESS"
    FAIL = "FAIL"


class JobStatus(enum.Enum):
    READY = "READY"
    PENDING = "PENDING"
    FINISHED = "FINISHED"
    RUNNING = "RUNNING"
    FAILED = "FAILED"
    DELETED = "DELETED"
    DOWNLOADED = "DOWNLOADED"
    GENERATED_LOCALLY = "GENERATED_LOCALLY"


@marshmallow_dataclass.dataclass
class RemoteScript:
    id: uuid.UUID
    name: str
    slug: str
    description: str
    status: ScriptStatus = dataclasses.field(metadata={"by_value": True})
    created_at: datetime.datetime
    updated_at: datetime.datetime
    user_id: uuid.UUID
    public: bool
    cpu_reservation: typing.Optional[int]
    cpu_limit: typing.Optional[int]
    memory_reservation: typing.Optional[int]
    memory_limit: typing.Optional[int]

    @post_load
    def set_timezone(self, data, **kwargs):
        data['created_at'] = data['created_at'].replace(
            tzinfo=datetime.timezone.utc
        )
        data['updated_at'] = data['updated_at'].replace(
            tzinfo=datetime.timezone.utc
        )

        return data


@marshmallow_dataclass.dataclass
class JobLocalContext:
    base_dir: Path = dataclasses.field(default=None)
    area_of_interest_name: str = dataclasses.field(default='unknown-area')


@marshmallow_dataclass.dataclass
class Job:
    id: uuid.UUID
    params: dict
    progress: int
    start_date: datetime.datetime
    status: JobStatus = dataclasses.field(metadata={"by_value": True})
    local_context: typing.Optional[JobLocalContext] = dataclasses.field(
        default_factory=JobLocalContext
    )
    results: typing.Optional[typing.Union[RasterResults, LocalResults,
                                          JsonResults, TimeSeriesTableResult,
                                          EmptyResults]
                             ] = dataclasses.field(default_factory=dict)
    task_name: typing.Optional[str] = None
    task_notes: typing.Optional[str] = None
    script: typing.Optional[ExecutionScript] = None
    end_date: typing.Optional[datetime.datetime] = None
    user_id: typing.Optional[uuid.UUID] = None

    @pre_load
    def set_script_name_version(self, data, **kwargs):
        script_id = data.pop('script_id', None)
        params_script = data['params'].pop('script', None)

        if not data.get('script'):
            if params_script:
                data['script'] = params_script
            elif script_id:
                data['script'] = ExecutionScript.Schema().dump(
                    ExecutionScript(script_id)
                )
            else:
                data['script'] = ExecutionScript.Schema().dump(
                    ExecutionScript("Unknown script")
                )

        script_name_regex = re.compile(
            '([0-9a-zA-Z -]*)(?: *)([0-9]+(_[0-9]+)+)'
        )
        matches = script_name_regex.search(data['script'].get('name'))

        if matches:
            data['script']['name'] = matches.group(1).rstrip()
            data['script']['version'] = matches.group(2).replace('_', '.')

        return data

    @pre_load
    def set_main_fields_from_params(self, data, **kwargs):
        field_names = ['task_name', 'task_notes', 'local_context']

        for field_name in field_names:
            field_value = None

            if field_name in data['params']:
                field_value = data['params'].pop(field_name)

            if not data.get(field_name) and field_value:
                data[field_name] = field_value

        return data

    @post_load
    def set_timezone(self, data, **kwargs):
        data['start_date'] = data['start_date'].replace(
            tzinfo=datetime.timezone.utc
        )

        if data['end_date']:
            data['end_date'] = data['end_date'].replace(
                tzinfo=datetime.timezone.utc
            )

        return data

    @property
    def visible_name(self) -> str:
        if self.script.name_readable:
            script_name = self.script.name_readable
        else:
            script_name = self.script.name

        if self.task_name and script_name:
            name = f"{self.task_name} ({script_name})"
        elif self.task_name:
            name = self.task_name + ' (unknown script)'
        elif script_name:
            name = script_name + ' (unnamed task)'
        else:
            name = "Unnamed task (unknown script)"

        return name
