from __future__ import annotations

import os
from pathlib import Path
from typing import Literal
from urllib.parse import urlparse

from pydantic import BaseModel, ConfigDict, Field, SecretStr, model_validator

from .schema import ForestStyle


class AppConfig(BaseModel):
    model_config = ConfigDict(extra="forbid")

    text_backend: Literal["demo", "hf_inference", "llama_cpp", "transformers", "modal"] = "demo"
    image_backend: Literal["demo", "flux", "hf_inference", "modal", "zerogpu"] = "demo"
    music_backend: Literal["none", "modal"] = "none"
    hf_text_model: str = "openbmb/MiniCPM4.1-8B"
    transformers_text_model: str = "openbmb/MiniCPM4.1-8B"
    hf_image_model: str = "black-forest-labs/FLUX.1-schnell"
    llama_base_url: str = "http://127.0.0.1:8080"
    llama_model: str = "compliment-forest-minicpm5-1b"
    flux_model_id: str = "black-forest-labs/FLUX.1-dev"
    flux_lora_id: str = "build-small-hackathon/compliment-forest-flux-lora"
    modal_text_endpoint: str | None = None
    modal_image_endpoint: str | None = None
    modal_music_endpoint: str | None = None
    modal_signing_key: SecretStr | None = None
    upstream_space_url: str | None = None
    local_files_only: bool = False
    default_seed: int = Field(default=3407, ge=0, le=2_147_483_647)
    default_style: ForestStyle = "surprise"
    trace_path: Path | None = None

    @model_validator(mode="after")
    def validate_local_text_server(self) -> AppConfig:
        if self.text_backend == "llama_cpp":
            hostname = urlparse(self.llama_base_url).hostname
            if hostname not in {"127.0.0.1", "localhost", "::1"}:
                raise ValueError("llama.cpp model server must be local")
        if self.text_backend == "modal":
            if not self.modal_text_endpoint or not self.modal_signing_key:
                raise ValueError("modal text backend requires endpoint credentials")
            if urlparse(self.modal_text_endpoint).scheme != "https":
                raise ValueError("modal text endpoint must use HTTPS")
        if self.image_backend == "modal":
            if not self.modal_image_endpoint or not self.modal_signing_key:
                raise ValueError("modal image backend requires endpoint credentials")
            if urlparse(self.modal_image_endpoint).scheme != "https":
                raise ValueError("modal image endpoint must use HTTPS")
        if self.music_backend == "modal":
            if not self.modal_music_endpoint or not self.modal_signing_key:
                raise ValueError("modal music backend requires endpoint credentials")
            if urlparse(self.modal_music_endpoint).scheme != "https":
                raise ValueError("modal music endpoint must use HTTPS")
        if self.upstream_space_url:
            parsed_upstream = urlparse(self.upstream_space_url)
            if parsed_upstream.scheme != "https" or not parsed_upstream.netloc:
                raise ValueError("upstream Space URL must use HTTPS")
        return self

    @classmethod
    def from_env(cls) -> AppConfig:
        trace_path = os.getenv("CF_TRACE_PATH")
        hosted_space = bool(os.getenv("SPACE_ID"))
        default_text_backend = "transformers" if hosted_space else "demo"
        default_image_backend = "zerogpu" if hosted_space else "demo"
        return cls(
            text_backend=os.getenv("CF_TEXT_BACKEND", default_text_backend),
            image_backend=os.getenv("CF_IMAGE_BACKEND", default_image_backend),
            music_backend=os.getenv("CF_MUSIC_BACKEND", "none"),
            hf_text_model=os.getenv(
                "CF_HF_TEXT_MODEL",
                "openbmb/MiniCPM4.1-8B",
            ),
            transformers_text_model=os.getenv(
                "CF_TRANSFORMERS_TEXT_MODEL",
                "openbmb/MiniCPM4.1-8B",
            ),
            hf_image_model=os.getenv(
                "CF_HF_IMAGE_MODEL",
                "black-forest-labs/FLUX.1-schnell",
            ),
            llama_base_url=os.getenv("CF_LLAMA_BASE_URL", "http://127.0.0.1:8080"),
            llama_model=os.getenv(
                "CF_LLAMA_MODEL",
                "compliment-forest-minicpm5-1b",
            ),
            flux_model_id=os.getenv(
                "CF_FLUX_MODEL_ID",
                "black-forest-labs/FLUX.1-dev",
            ),
            flux_lora_id=os.getenv(
                "CF_FLUX_LORA_ID",
                "build-small-hackathon/compliment-forest-flux-lora",
            ),
            modal_text_endpoint=os.getenv("CF_MODAL_TEXT_ENDPOINT"),
            modal_image_endpoint=os.getenv("CF_MODAL_IMAGE_ENDPOINT"),
            modal_music_endpoint=os.getenv("CF_MODAL_MUSIC_ENDPOINT"),
            modal_signing_key=(os.getenv("CF_MODAL_SIGNING_KEY") or os.getenv("HF_TOKEN")),
            upstream_space_url=os.getenv("CF_UPSTREAM_SPACE_URL"),
            local_files_only=os.getenv("CF_LOCAL_FILES_ONLY", "0") == "1",
            default_seed=int(os.getenv("CF_DEFAULT_SEED", "3407")),
            default_style=os.getenv("CF_DEFAULT_STYLE", "surprise"),
            trace_path=Path(trace_path) if trace_path else None,
        )