from __future__ import annotations

import os
from datetime import UTC, datetime
from enum import IntEnum
from importlib import resources
from importlib.resources.abc import Traversable
from pathlib import Path

from peewee import (
    BooleanField,
    Check,
    DateTimeField,
    ForeignKeyField,
    IntegerField,
    Model,
    SqliteDatabase,
    TextField,
)

DEFAULT_DB_PATH = Path("republisher.db")
DATABASE_PRAGMAS = {
    "busy_timeout": 5000,
    "cache_size": 15625,
    "foreign_keys": 1,
    "journal_mode": "wal",
    "page_size": 4096,
    "synchronous": "normal",
    "temp_store": "memory",
}
SCHEMA_GLOB = "*.sql"

database = SqliteDatabase(None, pragmas=DATABASE_PRAGMAS)


class JobExecutionStatus(IntEnum):
    PENDING = 0
    RUNNING = 1
    SUCCEEDED = 2
    FAILED = 3
    CANCELED = 4


def utc_now() -> datetime:
    return datetime.now(UTC)


def resolve_database_path(db_path: str | Path | None = None) -> Path:
    raw_value = (
        os.environ.get("REPUBLISHER_DB_PATH", DEFAULT_DB_PATH)
        if db_path is None
        else db_path
    )
    raw_path = Path(raw_value)
    return raw_path.expanduser().resolve()


def schema_paths() -> tuple[Traversable, ...]:
    schema_dir = resources.files("repub").joinpath("sql")
    return tuple(
        sorted(
            (path for path in schema_dir.iterdir() if path.name.endswith(".sql")),
            key=lambda path: path.name,
        )
    )


def initialize_database(db_path: str | Path | None = None) -> Path:
    resolved_path = resolve_database_path(db_path)
    resolved_path.parent.mkdir(parents=True, exist_ok=True)

    if not database.is_closed():
        database.close()

    database.init(str(resolved_path), pragmas=DATABASE_PRAGMAS)
    database.connect(reuse_if_open=True)
    try:
        connection = database.connection()
        for path in schema_paths():
            connection.executescript(path.read_text(encoding="utf-8"))
    finally:
        database.close()

    return resolved_path


class BaseModel(Model):
    class Meta:
        database = database


class Source(BaseModel):
    created_at = DateTimeField(default=utc_now)
    updated_at = DateTimeField(default=utc_now)
    name = TextField()
    slug = TextField(unique=True)
    source_type = TextField(constraints=[Check("source_type IN ('feed', 'pangea')")])
    notes = TextField(default="")

    class Meta:
        table_name = "source"


class SourceFeed(BaseModel):
    source = ForeignKeyField(Source, primary_key=True, backref="feed_config")
    feed_url = TextField()
    etag = TextField(null=True)
    last_modified = TextField(null=True)

    class Meta:
        table_name = "source_feed"


class SourcePangea(BaseModel):
    source = ForeignKeyField(Source, primary_key=True, backref="pangea_config")
    domain = TextField()
    category_name = TextField()
    content_type = TextField()
    only_newest = BooleanField()
    max_articles = IntegerField()
    oldest_article = IntegerField()
    include_authors = BooleanField()
    exclude_media = BooleanField()
    include_content = BooleanField()
    content_format = TextField()

    class Meta:
        table_name = "source_pangea"


class Job(BaseModel):
    source = ForeignKeyField(Source, unique=True, backref="job")
    created_at = DateTimeField(default=utc_now)
    updated_at = DateTimeField(default=utc_now)
    enabled = BooleanField()
    spider_arguments = TextField(default="")
    cron_minute = TextField()
    cron_hour = TextField()
    cron_day_of_month = TextField()
    cron_day_of_week = TextField()
    cron_month = TextField()

    class Meta:
        table_name = "job"


class JobExecution(BaseModel):
    job = ForeignKeyField(Job, backref="executions")
    created_at = DateTimeField(default=utc_now)
    started_at = DateTimeField(null=True)
    ended_at = DateTimeField(null=True)
    running_status = IntegerField(
        default=JobExecutionStatus.PENDING,
        constraints=[Check("running_status BETWEEN 0 AND 4")],
    )
    requests_count = IntegerField(default=0)
    items_count = IntegerField(default=0)
    warnings_count = IntegerField(default=0)
    errors_count = IntegerField(default=0)
    bytes_count = IntegerField(default=0)
    retries_count = IntegerField(default=0)
    exceptions_count = IntegerField(default=0)
    cache_size_count = IntegerField(default=0)
    cache_object_count = IntegerField(default=0)
    raw_stats = TextField(default="{}")

    class Meta:
        table_name = "job_execution"