from typing import Any

from sqlalchemy.orm import Session

from app.character.service import CharacterService
from app.config import get_settings
from app.homelab.anima_prompt import AnimaPromptBundle, build_draw_self_prompt, build_scene_tags_prompt, looks_like_booru_tags
from app.homelab.comfyui import ComfyUIClient
from app.integrations.rp_chat import RpChatClient


def _card_image_settings(db: Session, user_id: int) -> dict[str, Any]:
    return CharacterService(db, user_id).get_card().get("data", {})


def _session_messages(db: Session, session_id: int | None, limit: int = 8) -> list[dict[str, str]]:
    if not session_id:
        return []
    from sqlalchemy import select

    from app.db.models import Message

    rows = db.scalars(
        select(Message)
        .where(
            Message.session_id == session_id,
            Message.role.in_(("user", "assistant")),
        )
        .order_by(Message.created_at.desc())
        .limit(limit)
    ).all()
    rows = list(reversed(rows))
    return [{"role": m.role, "content": (m.content or "").strip()} for m in rows if m.content.strip()]


def _append_lora(positive: str, lora_name: str, lora_weight: float) -> str:
    if not lora_name or f"<lora:{lora_name}" in positive:
        return positive
    return f"{positive} <lora:{lora_name}:{lora_weight}>"


async def _generate_from_bundle(
    bundle: AnimaPromptBundle,
    *,
    backend: str,
    persona_id: str = "",
) -> dict[str, Any]:
    settings = get_settings()
    if backend == "rp_chat":
        client = RpChatClient()
        gen_result = await client.generate(bundle.positive, bundle.negative)
        if not gen_result.get("ok"):
            return gen_result
        saved = await client.save_image_locally(gen_result["image_path"])
        if not saved.get("ok"):
            return saved
        return {
            "ok": True,
            "url": saved["url"],
            "filename": saved["filename"],
            "prompt": bundle.positive,
            "negative_prompt": bundle.negative,
            "backend": "rp_chat",
            "persona_id": persona_id,
            "prompt_mode": "direct",
        }

    result = await ComfyUIClient().generate_image(
        bundle.positive,
        negative_prompt=bundle.negative,
    )
    if result.get("ok"):
        result["backend"] = "comfyui_local"
        result["prompt_mode"] = "direct"
        result["negative_prompt"] = bundle.negative
    return result


async def generate_image(
    db: Session,
    *,
    user_id: int,
    session_id: int | None = None,
    draw_self: bool = False,
    scene_description: str = "",
) -> dict[str, Any]:
    card = _card_image_settings(db, user_id)
    settings = get_settings()

    if not card.get("sd_enabled", True):
        return {"ok": False, "error": "Генерация изображений отключена в настройках персонажа"}

    if not draw_self and not scene_description.strip():
        return {"ok": False, "error": "Нужен draw_self=true или scene_description"}

    appearance = (card.get("appearance_tags") or "").strip()
    lora_name = (card.get("lora_name") or "").strip()
    lora_weight = float(card.get("lora_weight") or 0.8)
    persona_id = (card.get("rp_persona_id") or "").strip() or "default"
    backend = "rp_chat" if settings.rp_chat_enabled else "comfyui_local"

    if draw_self:
        if not appearance:
            return {
                "ok": False,
                "error": "Заполни appearance_tags в настройках персонажа для «нарисуй себя»",
            }
        bundle = build_draw_self_prompt(
            appearance,
            lora_name=lora_name,
            lora_weight=lora_weight,
        )
        return await _generate_from_bundle(bundle, backend=backend, persona_id=persona_id)

    scene = scene_description.strip()
    if looks_like_booru_tags(scene):
        if not appearance:
            bundle = build_scene_tags_prompt(scene, "", lora_name=lora_name, lora_weight=lora_weight)
        else:
            bundle = build_scene_tags_prompt(
                scene,
                appearance,
                lora_name=lora_name,
                lora_weight=lora_weight,
            )
        return await _generate_from_bundle(bundle, backend=backend, persona_id=persona_id)

    messages = _session_messages(db, session_id)
    messages = messages + [{"role": "user", "content": scene}]

    if settings.rp_chat_enabled:
        return await _generate_via_rp_chat(
            card,
            messages,
            appearance_override=appearance or None,
        )

    fallback = f"{appearance}, {scene}" if appearance else scene
    return await ComfyUIClient().generate_image(fallback)


async def _generate_via_rp_chat(
    card: dict[str, Any],
    messages: list[dict[str, str]],
    appearance_override: str | None,
) -> dict[str, Any]:
    client = RpChatClient()
    persona_id = (card.get("rp_persona_id") or "").strip() or "default"
    override = appearance_override or (card.get("appearance_tags") or "").strip() or None

    prompt_result = await client.sd_prompt(
        persona_id,
        messages,
        appearance_override=override,
    )
    if not prompt_result.get("ok"):
        return prompt_result

    positive = (
        prompt_result.get("hybrid_positive")
        or prompt_result.get("tag_positive")
        or ""
    ).strip()
    negative = (prompt_result.get("negative") or "").strip()
    if not positive:
        return {"ok": False, "error": "RP-чат не вернул промпт", "raw": prompt_result}

    lora = (card.get("lora_name") or "").strip()
    if lora:
        weight = float(card.get("lora_weight") or 0.8)
        positive = _append_lora(positive, lora, weight)

    gen_result = await client.generate(positive, negative)
    if not gen_result.get("ok"):
        return gen_result

    saved = await client.save_image_locally(gen_result["image_path"])
    if not saved.get("ok"):
        return saved

    return {
        "ok": True,
        "url": saved["url"],
        "filename": saved["filename"],
        "prompt": positive,
        "negative_prompt": negative,
        "backend": "rp_chat",
        "persona_id": persona_id,
        "prompt_mode": "llm",
    }