"""D 예정노선 1단계 기준 지정 — 지점 목록 API
(요구서 389 3장 1 · 440 1 · 445 A2 · 452 · PLAN 560-2 · 579-1 · 585-1 · 590-1).

- `GET /api/projects/{id}/plan/points` — {epsg, points: [점]} · 점 = {lon, lat, x, y}
- `PUT …/plan/points` — {points: [{lon, lat}]} → TM 셈 → 설계 내용 파일 `points`
  (`D03_PlanAnalysis_Store` · 좌표계 = 파일 머리 · 없으면 점 평균 경도의 TM 띠)
- 시점 · 종점 구분 없음 — 옛 꼴(DB `plan_base_json` · 연도 행 접기)은 저장 모듈의 옮김 몫.
- 고침 = 산림청만(지정 회사 GET 은 공용 판정 `require_project_access` 몫).
"""

from __future__ import annotations

from typing import Any
from uuid import UUID

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field

from common_util.common_util_auth import is_forest_service, require_company
from common_util.common_util_crs import lonlat_to_tm, tm_epsg_for_lon, tm_to_lonlat
from common_util.common_util_save_guard import project_lock
from D03_PlanAnalysis import D03_PlanAnalysis_Store as store

router = APIRouter(prefix="/api/projects", tags=["D02 Plan Base"])

MAX_POINTS = 40  # 지점 상한(옛 시점 20 + 종점 20)


class LonLat(BaseModel):
    lon: float = Field(..., ge=120, le=135)
    lat: float = Field(..., ge=30, le=45)


class BaseRequest(BaseModel):
    points: list[LonLat] = Field(default_factory=list, max_length=MAX_POINTS)


def _point(x: Any, y: Any, epsg: Any) -> dict[str, float] | None:
    if x is None or y is None or epsg is None:
        return None
    lon, lat = tm_to_lonlat(float(x), float(y), int(epsg))
    return {"lon": lon, "lat": lat, "x": float(x), "y": float(y)}


def base_view(plan: dict[str, Any]) -> dict[str, Any]:
    """{epsg, points} — 설계 내용의 지점(TM) + 경위도 · 지점이 없으면 epsg None."""
    epsg = plan.get("epsg")
    points = [p for p in (_point(i.get("x"), i.get("y"), epsg) for i in plan["points"]) if p]
    return {"epsg": epsg if points else None, "points": points}


async def load_base(project_id: UUID) -> dict[str, Any]:
    """지점 목록 — D03 이 읽는 길."""
    _, plan = await store.load_plan(project_id)
    return base_view(plan)


def stored_base(payload: BaseRequest, epsg: int | None = None) -> dict[str, Any]:
    """PUT 몸 → 파일 꼴(TM m) — 좌표계 = `epsg`(저장된 값) · 없으면 점 평균 경도의 TM 띠."""
    given = payload.points
    if not given:
        epsg = None
    elif epsg is None:
        epsg = tm_epsg_for_lon(sum(p.lon for p in given) / len(given))
    points = [dict(zip(("x", "y"), lonlat_to_tm(p.lon, p.lat, epsg))) for p in given]
    return {"epsg": epsg, "points": points}


@router.get("/{project_id}/plan/points", response_model=None)
async def get_plan_points(project_id: UUID) -> dict[str, Any]:
    return {"status": "success", **await load_base(project_id)}


@router.put("/{project_id}/plan/points", response_model=None)
async def put_plan_points(
    project_id: UUID,
    payload: BaseRequest,
    session: dict[str, Any] = Depends(require_company),
) -> dict[str, Any]:
    if not is_forest_service(session):
        raise HTTPException(status_code=403, detail="예정노선 지점은 산림청만 고칠 수 있습니다.")
    async with project_lock(str(project_id)):
        root, plan = await store.load_plan(project_id)  # 없음 · 예정노선 아님 거절
        base = stored_base(payload, plan["epsg"])
        epsg = plan["epsg"] if plan["lines"] else base["epsg"]  # 선이 있으면 좌표계 그대로
        plan = {**plan, "epsg": epsg, "points": base["points"]}
        store.save_plan(root, plan)
    return {"status": "success", **base_view(plan)}