"""The imap integration."""

from __future__ import annotations

import asyncio
from email.message import Message
import logging
from typing import Any

from aioimaplib import IMAP4_SSL, AioImapException, Response
import voluptuous as vol

from homeassistant.config_entries import ConfigEntry, ConfigEntryState
from homeassistant.const import EVENT_HOMEASSISTANT_STOP, Platform
from homeassistant.core import (
    HomeAssistant,
    ServiceCall,
    ServiceResponse,
    SupportsResponse,
    callback,
)
from homeassistant.exceptions import (
    ConfigEntryAuthFailed,
    ConfigEntryError,
    ConfigEntryNotReady,
    ServiceValidationError,
)
from homeassistant.helpers import config_validation as cv
from homeassistant.helpers.typing import ConfigType

from .const import CONF_ENABLE_PUSH, DOMAIN
from .coordinator import (
    ImapDataUpdateCoordinator,
    ImapMessage,
    ImapPollingDataUpdateCoordinator,
    ImapPushDataUpdateCoordinator,
    connect_to_server,
    get_parts,
)
from .errors import InvalidAuth, InvalidFolder

PLATFORMS: list[Platform] = [Platform.SENSOR]

CONF_ENTRY = "entry"
CONF_SEEN = "seen"
CONF_PART = "part"
CONF_UID = "uid"
CONF_TARGET_FOLDER = "target_folder"

_LOGGER = logging.getLogger(__name__)


CONFIG_SCHEMA = cv.config_entry_only_config_schema(DOMAIN)

_SERVICE_UID_SCHEMA = vol.Schema(
    {
        vol.Required(CONF_ENTRY): cv.string,
        vol.Required(CONF_UID): cv.string,
    }
)

SERVICE_SEEN_SCHEMA = _SERVICE_UID_SCHEMA
SERVICE_MOVE_SCHEMA = _SERVICE_UID_SCHEMA.extend(
    {
        vol.Optional(CONF_SEEN): cv.boolean,
        vol.Required(CONF_TARGET_FOLDER): cv.string,
    }
)
SERVICE_DELETE_SCHEMA = _SERVICE_UID_SCHEMA
SERVICE_FETCH_TEXT_SCHEMA = _SERVICE_UID_SCHEMA
SERVICE_FETCH_PART_SCHEMA = _SERVICE_UID_SCHEMA.extend(
    {
        vol.Required(CONF_PART): cv.string,
    }
)

type ImapConfigEntry = ConfigEntry[ImapDataUpdateCoordinator]


async def async_get_imap_client(hass: HomeAssistant, entry_id: str) -> IMAP4_SSL:
    """Get IMAP client and connect."""
    if (entry := hass.config_entries.async_get_entry(entry_id)) is None or (
        entry.state is not ConfigEntryState.LOADED
    ):
        raise ServiceValidationError(
            translation_domain=DOMAIN,
            translation_key="invalid_entry",
        )
    try:
        client = await connect_to_server(entry.data)
    except InvalidAuth as exc:
        raise ServiceValidationError(
            translation_domain=DOMAIN, translation_key="invalid_auth"
        ) from exc
    except InvalidFolder as exc:
        raise ServiceValidationError(
            translation_domain=DOMAIN, translation_key="invalid_folder"
        ) from exc
    except (TimeoutError, AioImapException) as exc:
        raise ServiceValidationError(
            translation_domain=DOMAIN,
            translation_key="imap_server_fail",
            translation_placeholders={"error": str(exc)},
        ) from exc
    return client


@callback
def raise_on_error(response: Response, translation_key: str) -> None:
    """Get error message from response."""
    if response.result != "OK":
        error: str = response.lines[0].decode("utf-8")
        raise ServiceValidationError(
            translation_domain=DOMAIN,
            translation_key=translation_key,
            translation_placeholders={"error": error},
        )


async def async_setup(hass: HomeAssistant, config: ConfigType) -> bool:
    """Set up imap services."""

    async def async_seen(call: ServiceCall) -> None:
        """Process mark as seen service call."""
        entry_id: str = call.data[CONF_ENTRY]
        uid: str = call.data[CONF_UID]
        _LOGGER.debug(
            "Mark message %s as seen. Entry: %s",
            uid,
            entry_id,
        )
        client = await async_get_imap_client(hass, entry_id)
        try:
            response = await client.store(uid, "+FLAGS (\\Seen)")
        except (TimeoutError, AioImapException) as exc:
            raise ServiceValidationError(
                translation_domain=DOMAIN,
                translation_key="imap_server_fail",
                translation_placeholders={"error": str(exc)},
            ) from exc
        raise_on_error(response, "seen_failed")
        await client.close()

    hass.services.async_register(DOMAIN, "seen", async_seen, SERVICE_SEEN_SCHEMA)

    async def async_move(call: ServiceCall) -> None:
        """Process move email service call."""
        entry_id: str = call.data[CONF_ENTRY]
        uid: str = call.data[CONF_UID]
        seen = bool(call.data.get(CONF_SEEN))
        target_folder: str = call.data[CONF_TARGET_FOLDER]
        _LOGGER.debug(
            "Move message %s to folder %s. Mark as seen: %s. Entry: %s",
            uid,
            target_folder,
            seen,
            entry_id,
        )
        client = await async_get_imap_client(hass, entry_id)
        try:
            if seen:
                response = await client.store(uid, "+FLAGS (\\Seen)")
                raise_on_error(response, "seen_failed")
            response = await client.copy(uid, target_folder)
            raise_on_error(response, "copy_failed")
            response = await client.store(uid, "+FLAGS (\\Deleted)")
            raise_on_error(response, "delete_failed")
            response = await asyncio.wait_for(
                client.protocol.expunge(uid, by_uid=True), client.timeout
            )
            raise_on_error(response, "expunge_failed")
        except (TimeoutError, AioImapException) as exc:
            raise ServiceValidationError(
                translation_domain=DOMAIN,
                translation_key="imap_server_fail",
                translation_placeholders={"error": str(exc)},
            ) from exc
        await client.close()

    hass.services.async_register(DOMAIN, "move", async_move, SERVICE_MOVE_SCHEMA)

    async def async_delete(call: ServiceCall) -> None:
        """Process deleting email service call."""
        entry_id: str = call.data[CONF_ENTRY]
        uid: str = call.data[CONF_UID]
        _LOGGER.debug(
            "Delete message %s. Entry: %s",
            uid,
            entry_id,
        )
        client = await async_get_imap_client(hass, entry_id)
        try:
            response = await client.store(uid, "+FLAGS (\\Deleted)")
            raise_on_error(response, "delete_failed")
            response = await asyncio.wait_for(
                client.protocol.expunge(uid, by_uid=True), client.timeout
            )
            raise_on_error(response, "expunge_failed")
        except (TimeoutError, AioImapException) as exc:
            raise ServiceValidationError(
                translation_domain=DOMAIN,
                translation_key="imap_server_fail",
                translation_placeholders={"error": str(exc)},
            ) from exc
        await client.close()

    hass.services.async_register(DOMAIN, "delete", async_delete, SERVICE_DELETE_SCHEMA)

    async def async_fetch(call: ServiceCall) -> ServiceResponse:
        """Process fetch email service and return content."""
        entry_id: str = call.data[CONF_ENTRY]
        uid: str = call.data[CONF_UID]
        _LOGGER.debug(
            "Fetch text for message %s. Entry: %s",
            uid,
            entry_id,
        )
        client = await async_get_imap_client(hass, entry_id)
        try:
            response = await client.fetch(uid, "BODY.PEEK[]")
        except (TimeoutError, AioImapException) as exc:
            raise ServiceValidationError(
                translation_domain=DOMAIN,
                translation_key="imap_server_fail",
                translation_placeholders={"error": str(exc)},
            ) from exc
        raise_on_error(response, "fetch_failed")
        # Index 1 of of the response lines contains the bytearray with the message data
        message = ImapMessage(response.lines[1])
        await client.close()
        return {
            "text": message.text,
            "sender": message.sender,
            "subject": message.subject,
            "parts": get_parts(message.email_message),
            "uid": uid,
        }

    hass.services.async_register(
        DOMAIN,
        "fetch",
        async_fetch,
        SERVICE_FETCH_TEXT_SCHEMA,
        supports_response=SupportsResponse.ONLY,
    )

    async def async_fetch_part(call: ServiceCall) -> ServiceResponse:
        """Process fetch email part service and return content."""

        @callback
        def get_message_part(message: Message, part_key: str) -> Message:
            part: Message | Any = message
            for index in part_key.split(","):
                sub_parts = part.get_payload()
                try:
                    assert isinstance(sub_parts, list)
                    part = sub_parts[int(index)]
                except (AssertionError, ValueError, IndexError) as exc:
                    raise ServiceValidationError(
                        translation_domain=DOMAIN,
                        translation_key="invalid_part_index",
                    ) from exc

            return part

        entry_id: str = call.data[CONF_ENTRY]
        uid: str = call.data[CONF_UID]
        part_key: str = call.data[CONF_PART]
        _LOGGER.debug(
            "Fetch part %s for message %s. Entry: %s",
            part_key,
            uid,
            entry_id,
        )
        client = await async_get_imap_client(hass, entry_id)
        try:
            response = await client.fetch(uid, "BODY.PEEK[]")
        except (TimeoutError, AioImapException) as exc:
            raise ServiceValidationError(
                translation_domain=DOMAIN,
                translation_key="imap_server_fail",
                translation_placeholders={"error": str(exc)},
            ) from exc
        raise_on_error(response, "fetch_failed")
        # Index 1 of of the response lines contains the bytearray with the message data
        message = ImapMessage(response.lines[1])
        await client.close()
        part_data = get_message_part(message.email_message, part_key)
        part_data_content = part_data.get_payload(decode=False)
        try:
            assert isinstance(part_data_content, str)
        except AssertionError as exc:
            raise ServiceValidationError(
                translation_domain=DOMAIN,
                translation_key="invalid_part_index",
            ) from exc
        return {
            "part_data": part_data_content,
            "content_type": part_data.get_content_type(),
            "content_transfer_encoding": part_data.get("Content-Transfer-Encoding"),
            "filename": part_data.get_filename(),
            "part": part_key,
            "uid": uid,
        }

    hass.services.async_register(
        DOMAIN,
        "fetch_part",
        async_fetch_part,
        SERVICE_FETCH_PART_SCHEMA,
        supports_response=SupportsResponse.ONLY,
    )

    return True


async def async_setup_entry(hass: HomeAssistant, entry: ImapConfigEntry) -> bool:
    """Set up imap from a config entry."""
    try:
        imap_client: IMAP4_SSL = await connect_to_server(dict(entry.data))
    except InvalidAuth as err:
        raise ConfigEntryAuthFailed from err
    except InvalidFolder as err:
        raise ConfigEntryError("Selected mailbox folder is invalid.") from err
    except (TimeoutError, AioImapException) as err:
        raise ConfigEntryNotReady from err

    coordinator_class: type[
        ImapPushDataUpdateCoordinator | ImapPollingDataUpdateCoordinator
    ]
    enable_push: bool = entry.data.get(CONF_ENABLE_PUSH, True)
    if enable_push and imap_client.has_capability("IDLE"):
        coordinator_class = ImapPushDataUpdateCoordinator
    else:
        coordinator_class = ImapPollingDataUpdateCoordinator

    coordinator: ImapDataUpdateCoordinator = coordinator_class(hass, imap_client, entry)
    await coordinator.async_config_entry_first_refresh()

    entry.runtime_data = coordinator

    entry.async_on_unload(
        hass.bus.async_listen_once(EVENT_HOMEASSISTANT_STOP, coordinator.shutdown)
    )

    await hass.config_entries.async_forward_entry_setups(entry, PLATFORMS)

    return True


async def async_unload_entry(hass: HomeAssistant, entry: ImapConfigEntry) -> bool:
    """Unload a config entry."""
    if unload_ok := await hass.config_entries.async_unload_platforms(entry, PLATFORMS):
        coordinator = entry.runtime_data
        await coordinator.shutdown()
    return unload_ok