"""The timer endpoints. Thin: every decision lives in `services.pomodoro`."""

from __future__ import annotations

from datetime import date

from fastapi import APIRouter, HTTPException, Query

from app.api.deps import DbSession, Settings
from app.api.schemas import (
    AbandonRequest,
    AttachTaskRequest,
    CompleteTimerRequest,
    ExtendRequest,
    StartTimerRequest,
)
from app.services import pomodoro, report, stats
from app.services.notify import count_sent, notify, record_sent
from app.timeutil import local_date

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


@router.get("/state")
def get_state(session: DbSession, settings: Settings) -> dict:
    return pomodoro.state(session, settings)


@router.post("/start")
def start(body: StartTimerRequest, session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.start(
            session,
            settings,
            kind=body.kind,
            minutes=body.minutes,
            task_id=body.task_id,
            note=body.note,
        )
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.post("/pause")
def pause(session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.pause(session, settings)
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.post("/resume")
def resume(session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.resume(session)
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.post("/complete")
def complete(body: CompleteTimerRequest, session: DbSession, settings: Settings) -> dict:
    try:
        finished, follow_on = pomodoro.complete(
            session,
            settings,
            auto_next=body.auto_next,
            expect_id=body.session_id,
        )
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc

    # `finished` is None when the named interval was no longer the running one:
    # nothing happened, so there is nothing to celebrate and nothing to announce.
    celebration = _maybe_celebrate(session, settings) if finished and finished.is_work else None
    state = pomodoro.state(session, settings)
    state["finished"] = pomodoro.session_dict(finished)
    state["auto_started"] = pomodoro.session_dict(follow_on)
    state["celebration"] = celebration
    return state


@router.post("/abandon")
def abandon(body: AbandonRequest, session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.abandon(session, settings, reason=body.reason)
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.post("/interrupt")
def interrupt(session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.add_interruption(session)
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.post("/extend")
def extend(body: ExtendRequest, session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.extend(session, body.minutes)
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.post("/task")
def attach_task(body: AttachTaskRequest, session: DbSession, settings: Settings) -> dict:
    try:
        pomodoro.attach_task(session, body.task_id)
    except pomodoro.TimerError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    return pomodoro.state(session, settings)


@router.get("/sessions")
def sessions(
    session: DbSession,
    settings: Settings,
    day: date | None = Query(default=None, description="Local date; defaults to today."),
) -> dict:
    target = day or local_date(settings.timezone)
    rows = pomodoro.sessions_for_day(session, settings, target)
    return {
        "date": target.isoformat(),
        "sessions": [pomodoro.session_dict(row) for row in rows],
        "metrics": stats.day_metrics(session, settings, target),
    }


def _maybe_celebrate(session, settings) -> str | None:
    """Cheer in Telegram every N pomodoros — the cheapest dopamine there is."""
    every = settings.notifications.telegram.celebrate_every_n_pomodoros
    if not (settings.notifications.telegram.enabled and every):
        return None

    done = pomodoro.completed_work_today(session, settings)
    if done == 0 or done % every != 0:
        return None

    today = local_date(settings.timezone)
    kind = f"celebrate:{done}"
    if count_sent(session, kind, today):
        return None

    ru = settings.notifications.report.language == "ru"
    goal = settings.pomodoro.daily_goal_pomodoros
    bar = report.progress_bar(done, goal)
    text = (
        f"🎉 <b>{done}</b> помидорок готово!\n{bar} {done}/{goal}\nДержи темп."
        if ru
        else f"🎉 <b>{done}</b> pomodoros done!\n{bar} {done}/{goal}\nKeep the rhythm."
    )
    deliveries = notify(settings, text)
    if any(delivery.ok for delivery in deliveries):
        record_sent(session, kind, today, {"pomodoros": done})
    return text