"""
Runtime config endpoint for the detection pipeline.

GET  /detect/config          — read current config
PUT  /detect/config          — update config (takes effect on next run)
GET  /detect/config/stages   — list stage palette with config fields
"""

from __future__ import annotations

import logging

from fastapi import APIRouter
from pydantic import BaseModel

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/detect", tags=["detect"])

# In-memory config — persists until server restart.
# Phase 12+ moves this to DB.
_runtime_config: dict = {}


class ConfigUpdate(BaseModel):
    detection: dict | None = None
    ocr: dict | None = None
    resolver: dict | None = None
    escalation: dict | None = None
    preprocessing: dict | None = None


class StageConfigInfo(BaseModel):
    name: str
    label: str
    description: str
    category: str
    config_fields: list[dict]
    reads: list[str]
    writes: list[str]


@router.get("/config")
def read_config():
    return _runtime_config


@router.put("/config")
def write_config(update: ConfigUpdate):
    changes = update.model_dump(exclude_none=True)
    for section, values in changes.items():
        if section not in _runtime_config:
            _runtime_config[section] = {}
        _runtime_config[section].update(values)

    logger.info("Config updated: %s", list(changes.keys()))
    return _runtime_config


@router.get("/config/stages", response_model=list[StageConfigInfo])
def list_stage_configs():
    """Return the stage palette with config field metadata for the editor."""
    from detect.stages import list_stages

    result = []
    for stage in list_stages():
        info = StageConfigInfo(
            name=stage.name,
            label=stage.label,
            description=stage.description,
            category=stage.category,
            config_fields=[
                {
                    "name": f.name,
                    "type": f.type,
                    "default": f.default,
                    "description": f.description,
                    "min": f.min,
                    "max": f.max,
                    "options": f.options,
                }
                for f in stage.config_fields
            ],
            reads=stage.io.reads,
            writes=stage.io.writes,
        )
        result.append(info)
    return result