"""Workflow plan builders for generation harness workflows."""

from dataclasses import dataclass
from enum import StrEnum
from typing import Any

from app.services.harness.types import ArtifactKind, WorkflowStep


class WorkflowMode(StrEnum):
    """Supported executable workflow modes."""

    STORY = "story"
    STORY_WITH_ASSETS = "story_with_assets"
    STORYBOOK = "storybook"
    ASSET_GENERATION = "asset_generation"
    ASSET_RETRY = "asset_retry"


@dataclass(frozen=True)
class WorkflowTask:
    """One planned step in a generation workflow."""

    key: str
    step: WorkflowStep
    artifact: ArtifactKind
    required: bool = True
    recoverable: bool = False

    def to_snapshot(self) -> dict[str, Any]:
        """Return a JSON-safe snapshot for tests and trace metadata."""

        return {
            "key": self.key,
            "step": self.step.value,
            "artifact": self.artifact.value,
            "required": self.required,
            "recoverable": self.recoverable,
        }


@dataclass(frozen=True)
class WorkflowPlan:
    """Declarative shape of a generation workflow before execution."""

    mode: WorkflowMode
    tasks: tuple[WorkflowTask, ...]

    def to_snapshot(self) -> dict[str, Any]:
        """Return a JSON-safe snapshot for tests and trace metadata."""

        return {
            "mode": self.mode.value,
            "tasks": [task.to_snapshot() for task in self.tasks],
        }


def build_story_plan(*, generate_images: bool) -> WorkflowPlan:
    """Build a plan for a text story generation request."""

    tasks = [
        WorkflowTask(
            key="prepare_context",
            step=WorkflowStep.CONTEXT_PREPARATION,
            artifact=ArtifactKind.NONE,
        ),
        WorkflowTask(
            key="generate_narrative",
            step=WorkflowStep.NARRATIVE_GENERATION,
            artifact=ArtifactKind.STORY_TEXT,
        ),
        WorkflowTask(
            key="evaluate_narrative",
            step=WorkflowStep.EVALUATION,
            artifact=ArtifactKind.STORY_TEXT,
        ),
        WorkflowTask(
            key="persist_story",
            step=WorkflowStep.STORY_PERSISTENCE,
            artifact=ArtifactKind.STORY_TEXT,
        ),
    ]

    if generate_images:
        tasks.append(
            WorkflowTask(
                key="generate_cover_image",
                step=WorkflowStep.IMAGE_GENERATION,
                artifact=ArtifactKind.COVER_IMAGE,
                required=False,
                recoverable=True,
            )
        )

    tasks.extend(
        [
            WorkflowTask(
                key="queue_postprocessing",
                step=WorkflowStep.POSTPROCESSING,
                artifact=ArtifactKind.ACHIEVEMENT_MEMORY,
                required=False,
                recoverable=True,
            ),
            WorkflowTask(
                key="complete_generation",
                step=WorkflowStep.COMPLETION,
                artifact=ArtifactKind.NONE,
            ),
        ]
    )

    return WorkflowPlan(
        mode=WorkflowMode.STORY_WITH_ASSETS if generate_images else WorkflowMode.STORY,
        tasks=tuple(tasks),
    )


def build_storybook_plan(*, generate_images: bool) -> WorkflowPlan:
    """Build a plan for a storybook generation request."""

    tasks = [
        WorkflowTask(
            key="prepare_context",
            step=WorkflowStep.CONTEXT_PREPARATION,
            artifact=ArtifactKind.NONE,
        ),
        WorkflowTask(
            key="generate_storybook_pages",
            step=WorkflowStep.NARRATIVE_GENERATION,
            artifact=ArtifactKind.STORYBOOK_PAGES,
        ),
        WorkflowTask(
            key="evaluate_storybook_pages",
            step=WorkflowStep.EVALUATION,
            artifact=ArtifactKind.STORYBOOK_PAGES,
        ),
    ]

    if generate_images:
        tasks.append(
            WorkflowTask(
                key="generate_storybook_images",
                step=WorkflowStep.IMAGE_GENERATION,
                artifact=ArtifactKind.IMAGE,
                required=False,
                recoverable=True,
            )
        )

    tasks.extend(
        [
            WorkflowTask(
                key="persist_storybook",
                step=WorkflowStep.STORY_PERSISTENCE,
                artifact=ArtifactKind.STORYBOOK_PAGES,
            ),
            WorkflowTask(
                key="queue_postprocessing",
                step=WorkflowStep.POSTPROCESSING,
                artifact=ArtifactKind.ACHIEVEMENT_MEMORY,
                required=False,
                recoverable=True,
            ),
            WorkflowTask(
                key="complete_generation",
                step=WorkflowStep.COMPLETION,
                artifact=ArtifactKind.NONE,
            ),
        ]
    )

    return WorkflowPlan(mode=WorkflowMode.STORYBOOK, tasks=tuple(tasks))


def build_asset_plan(*, output_mode: str, assets: list[str]) -> WorkflowPlan:
    """Build a plan for asset generation or retry jobs."""

    mode = (
        WorkflowMode.ASSET_RETRY
        if output_mode == WorkflowMode.ASSET_RETRY.value
        else WorkflowMode.ASSET_GENERATION
    )
    initial_step = (
        WorkflowStep.ASSET_RETRY
        if mode == WorkflowMode.ASSET_RETRY
        else WorkflowStep.ASSET_GENERATION
    )
    initial_key = (
        "start_asset_retry"
        if mode == WorkflowMode.ASSET_RETRY
        else "start_asset_generation"
    )
    completion_key = (
        "complete_asset_retry"
        if mode == WorkflowMode.ASSET_RETRY
        else "complete_asset_generation"
    )

    tasks = [
        WorkflowTask(
            key=initial_key,
            step=initial_step,
            artifact=ArtifactKind.NONE,
        )
    ]

    for asset in dict.fromkeys(assets):
        if asset == "image":
            tasks.append(
                WorkflowTask(
                    key="complete_image_asset",
                    step=WorkflowStep.IMAGE_GENERATION,
                    artifact=ArtifactKind.IMAGE,
                    required=False,
                    recoverable=True,
                )
            )
        elif asset == "audio":
            tasks.append(
                WorkflowTask(
                    key="complete_audio_asset",
                    step=WorkflowStep.AUDIO_GENERATION,
                    artifact=ArtifactKind.AUDIO,
                    required=False,
                    recoverable=True,
                )
            )
        else:
            tasks.append(
                WorkflowTask(
                    key=f"complete_{asset}_asset",
                    step=WorkflowStep.UNKNOWN,
                    artifact=ArtifactKind.UNKNOWN,
                    required=False,
                    recoverable=True,
                )
            )

    tasks.append(
        WorkflowTask(
            key=completion_key,
            step=initial_step,
            artifact=ArtifactKind.NONE,
        )
    )

    return WorkflowPlan(mode=mode, tasks=tuple(tasks))