from __future__ import annotations

from typing import Any, TypeAlias

from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.enums.generation_status import GenerationRecordPipelineStage, GenerationStatus
from app.enums.generation_task import ChatGenerationPipelineStage, ChatGenerationTaskStatus
from app.models.chat_generation_task import ChatGenerationTask
from app.models.generation_record import GenerationRecord
from app.models.video_upscale_task import VideoUpscaleTask
from app.services.generation.pipeline.db_lock_service import apply_short_lock_timeout

VideoUpscaleOwner: TypeAlias = ChatGenerationTask | GenerationRecord


def owner_type(owner: VideoUpscaleOwner | None) -> str | None:
    if isinstance(owner, ChatGenerationTask):
        return "chat_generation_task"
    if isinstance(owner, GenerationRecord):
        return "generation_record"
    return None


def owner_id(owner: VideoUpscaleOwner | None) -> str | None:
    return str(getattr(owner, "id", "") or "") or None


def owner_is_generating(owner: VideoUpscaleOwner) -> bool:
    if isinstance(owner, ChatGenerationTask):
        return owner.status == ChatGenerationTaskStatus.GENERATING.value
    return owner.status == GenerationStatus.generating.value


def owner_is_completed(owner: VideoUpscaleOwner) -> bool:
    if isinstance(owner, ChatGenerationTask):
        return owner.status == ChatGenerationTaskStatus.COMPLETED.value
    return owner.status == GenerationStatus.completed.value


def set_owner_stage(owner: VideoUpscaleOwner, stage: str) -> None:
    owner.pipeline_stage = stage


def upscale_stage_value(owner: VideoUpscaleOwner, chat_stage: ChatGenerationPipelineStage | str) -> str:
    value = chat_stage.value if hasattr(chat_stage, "value") else str(chat_stage)
    if isinstance(owner, ChatGenerationTask):
        return value
    try:
        return GenerationRecordPipelineStage(value).value
    except ValueError:
        return value


async def load_upscale_owner(
    db: AsyncSession,
    upscale: VideoUpscaleTask,
    *,
    for_update: bool,
) -> VideoUpscaleOwner | None:
    if upscale.chat_generation_task_id:
        query = select(ChatGenerationTask).where(
            ChatGenerationTask.id == upscale.chat_generation_task_id,
            ChatGenerationTask.deleted_at.is_(None),
        )
    elif upscale.generation_record_id:
        query = select(GenerationRecord).where(
            GenerationRecord.id == upscale.generation_record_id,
            GenerationRecord.deleted_at.is_(None),
        )
    else:
        return None
    if for_update:
        await apply_short_lock_timeout(db)
        query = query.with_for_update()
    result = await db.execute(query.limit(1))
    return result.scalar_one_or_none()


async def mark_owner_upscale_failed(
    db: AsyncSession,
    owner: VideoUpscaleOwner,
    *,
    error_message: str,
) -> None:
    if isinstance(owner, ChatGenerationTask):
        owner.status = ChatGenerationTaskStatus.FAILED.value
        owner.pipeline_stage = ChatGenerationPipelineStage.UPSCALE_FAILED.value
        owner.error_message = error_message
        return

    owner.status = GenerationStatus.failed.value
    owner.pipeline_stage = GenerationRecordPipelineStage.UPSCALE_FAILED.value
    owner.error_message = error_message


def restore_owner_for_upscale_retry(owner: VideoUpscaleOwner) -> None:
    if isinstance(owner, ChatGenerationTask):
        owner.status = ChatGenerationTaskStatus.GENERATING.value
        owner.pipeline_stage = ChatGenerationPipelineStage.UPSCALE_QUEUED.value
    else:
        owner.status = GenerationStatus.generating.value
        owner.pipeline_stage = GenerationRecordPipelineStage.UPSCALE_QUEUED.value
    owner.error_message = None


def owner_context(owner: VideoUpscaleOwner | None) -> dict[str, Any]:
    if owner is None:
        return {}
    return {
        "owner_type": owner_type(owner),
        "owner_id": owner_id(owner),
        "chat_generation_task_id": owner.id if isinstance(owner, ChatGenerationTask) else None,
        "generation_record_id": owner.id if isinstance(owner, GenerationRecord) else None,
        "project_id": getattr(owner, "project_id", None),
        "generation_mode": getattr(owner, "generation_mode", None),
    }