"""Post-award milestone API."""
from __future__ import annotations

import datetime
from typing import Optional

from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field
from sqlalchemy.orm import Session

from core.post_award.service import (
    create_milestone,
    delete_milestone,
    list_milestones,
    milestone_to_dict,
    update_milestone,
)
from core.subscription.middleware import verify_token
from endpoints.projects import get_db

router = APIRouter(prefix="/api/projects", tags=["post-award"])


class MilestoneCreateBody(BaseModel):
    title: str = Field(..., min_length=1, max_length=200)
    due_date: str = Field(..., description="ISO datetime")
    description: Optional[str] = None
    status: str = "pending"


class MilestoneUpdateBody(BaseModel):
    title: Optional[str] = Field(None, min_length=1, max_length=200)
    due_date: Optional[str] = None
    description: Optional[str] = None
    status: Optional[str] = None


def _tenant_id(token_data: dict) -> str:
    return token_data.get("sub") or token_data.get("user_id") or "anonymous"


def _parse_iso(value: str) -> datetime.datetime:
    try:
        dt = datetime.datetime.fromisoformat(value.replace("Z", "+00:00"))
    except ValueError as exc:
        raise HTTPException(status_code=400, detail="Nieprawidłowy format daty (ISO).") from exc
    if dt.tzinfo is None:
        dt = dt.replace(tzinfo=datetime.timezone.utc)
    return dt


@router.get("/{project_id}/post-award/milestones")
async def get_milestones(
    project_id: str,
    token_data: dict = Depends(verify_token),
    db: Session = Depends(get_db),
):
    clerk_id = _tenant_id(token_data)
    rows = list_milestones(db, project_id, clerk_id)
    if rows == []:
        from core.projects.models import Project

        exists = (
            db.query(Project)
            .filter(Project.id == project_id, Project.clerk_user_id == clerk_id)
            .first()
        )
        if not exists:
            raise HTTPException(status_code=404, detail="Projekt nie znaleziony")
    return {"milestones": [milestone_to_dict(r) for r in rows], "count": len(rows)}


@router.post("/{project_id}/post-award/milestones")
async def add_milestone(
    project_id: str,
    body: MilestoneCreateBody,
    token_data: dict = Depends(verify_token),
    db: Session = Depends(get_db),
):
    clerk_id = _tenant_id(token_data)
    try:
        row = create_milestone(
            db,
            project_id,
            clerk_id,
            title=body.title,
            due_date=_parse_iso(body.due_date),
            description=body.description,
            status=body.status,
        )
    except ValueError:
        raise HTTPException(status_code=404, detail="Projekt nie znaleziony")
    return milestone_to_dict(row)


@router.patch("/{project_id}/post-award/milestones/{milestone_id}")
async def patch_milestone(
    project_id: str,
    milestone_id: str,
    body: MilestoneUpdateBody,
    token_data: dict = Depends(verify_token),
    db: Session = Depends(get_db),
):
    clerk_id = _tenant_id(token_data)
    fields = body.model_dump(exclude_unset=True)
    if "due_date" in fields and fields["due_date"]:
        fields["due_date"] = _parse_iso(fields["due_date"])
    row = update_milestone(db, milestone_id, clerk_id, **fields)
    if not row or row.project_id != project_id:
        raise HTTPException(status_code=404, detail="Kamień milowy nie znaleziony")
    return milestone_to_dict(row)


@router.delete("/{project_id}/post-award/milestones/{milestone_id}")
async def remove_milestone(
    project_id: str,
    milestone_id: str,
    token_data: dict = Depends(verify_token),
    db: Session = Depends(get_db),
):
    clerk_id = _tenant_id(token_data)
    from core.projects.models import ProjectMilestone

    row = (
        db.query(ProjectMilestone)
        .filter(ProjectMilestone.id == milestone_id, ProjectMilestone.clerk_user_id == clerk_id)
        .first()
    )
    if not row or row.project_id != project_id:
        raise HTTPException(status_code=404, detail="Kamień milowy nie znaleziony")
    delete_milestone(db, milestone_id, clerk_id)
    return {"status": "removed", "id": milestone_id}