"""예정노선 다시 추적(626-2 · 요구 530) — 고친 예정노선 → 평면선(노드 · 곡선 · 편집표) · 저장 0.

계산 자리 ③ 서버 단독 — 체인 초기 폴리라인(`_ensure_planned_initial`)과 같은 함수
`followed_table`(지형 안 씀 · 순수 기하). 화면은 받은 노드를 편집기 한 걸음으로 싣고 페이지 [저장]
길로 보냄(고친 예정노선 = 초안 `expected` → `expected_route_edit.csv`). `/route/replan` ·
`as_initial` · `expected_route.csv` · 초기값 · 추천 저장본은 안 건드림.

  POST /api/projects/{id}/route/follow
    본문 {points: [[x, y], …], crs: "tm" | "lonlat"}   ("lonlat" = [경도, 위도])
    → {status, planned, nodes, curves, node_edits, station_snap, min_radius_m,
       curve_count, violation_count}   (GET /route/plan 칸 이름 · 사업지 TM)
    400 점 2 미만 · 404 프로젝트 없음 · 409 좌표계 모름(lonlat)
"""

from __future__ import annotations

import asyncio
from typing import Any, Literal
from uuid import UUID

from fastapi.responses import JSONResponse
from pydantic import BaseModel

from B05_Profile.B05_Profile_Repository import get_surface_crs_epsg
from B05_Profile.B05_Profile_Route_Polyline_Write import followed_table
from B05_Profile.B05_Profile_Router_Replan import (
    _PROJECT_PATH_MISSING,
    _plan_criteria,
    _project_paths,
    router,
)
from common_util.common_util_crs import lonlat_to_tm
from config.config_db import get_db_pool


class RouteFollowRequest(BaseModel):
    points: list[tuple[float, float]]
    crs: Literal["tm", "lonlat"] = "tm"


def follow_route_line(points: list[tuple[float, float]], radius_m: float) -> dict[str, Any]:
    """점 묶음(TM) → 예정노선 추적 평면선 — 파일 꼴(csv 4자리)과 같은 값."""
    result, table = followed_table(points, radius_m)
    return {
        "planned": [[round(x, 4), round(y, 4)] for x, y in result.vertices],
        "nodes": [node.as_dict() for node in result.nodes],
        "curves": table["curves"],
        "node_edits": table.get("edits"),
        "station_snap": table["station_snap"],
        "min_radius_m": round(radius_m, 2),
        "curve_count": result.curve_count,
        "violation_count": result.violation_count,
    }


@router.post("/{project_id}/route/follow", response_model=None)
async def follow_route(project_id: UUID, body: RouteFollowRequest) -> dict[str, Any] | JSONResponse:
    """고친 예정노선을 다시 추적한 평면선 — 아무것도 안 씀(626-2)."""
    if len(body.points) < 2:
        return JSONResponse(
            status_code=400,
            content={"status": "error", "message": "예정노선은 점이 2개 이상이어야 합니다."},
        )
    if await _project_paths(project_id) is None:
        return JSONResponse(status_code=404, content=_PROJECT_PATH_MISSING)
    points = [(float(x), float(y)) for x, y in body.points]
    if body.crs == "lonlat":
        async with get_db_pool().acquire() as connection:
            epsg = await get_surface_crs_epsg(connection, project_id, 0)
        if epsg is None:
            return JSONResponse(
                status_code=409,
                content={
                    "status": "error",
                    "message": "사업지 좌표계를 몰라 경위도를 바꿀 수 없습니다.",
                },
            )
        points = [lonlat_to_tm(lon, lat, epsg) for lon, lat in points]
    radius_m = (await _plan_criteria(project_id))[0]
    line = await asyncio.to_thread(follow_route_line, points, radius_m)
    return {"status": "success", "project_id": str(project_id), **line}