"""ESPresso Frame server: pulls photos from Immich, pre-processes them for
the panel, and serves the ESP32 a ready-to-display frame."""

from __future__ import annotations

import io
import logging
import time
from datetime import datetime, timedelta
from zoneinfo import ZoneInfo, available_timezones

import httpx
from fastapi import Depends, FastAPI, File, HTTPException, Form, Request, UploadFile
from fastapi.responses import FileResponse, HTMLResponse, RedirectResponse, Response
from fastapi.templating import Jinja2Templates
from PIL import Image
from pydantic import BaseModel

from . import config, gitea_releases, photo_queue
from .face_labels import compute_face_labels
from .firmware import firmware_path, parse_app_version
from .image_pipeline import render_frame
from .immich_client import ImmichClient

logger = logging.getLogger(__name__)

app = FastAPI(title="ESPresso Frame Server")
templates = Jinja2Templates(directory="app/templates")

MIN_REFRESH_INTERVAL_S = 60
MAX_REFRESH_INTERVAL_S = 86400
MIN_QUEUE_TARGET_LEN = 5
MAX_QUEUE_TARGET_LEN = 5000

ORIENTATIONS = ("landscape", "portrait", "landscape_flipped", "portrait_flipped")

# Populated once from the OS's zoneinfo database (installed via the
# `tzdata` apt package in the Dockerfile) and offered as a <select> in the
# web UI's "Timezone" field -- see api_config_save/index below.
ALL_TIMEZONES = sorted(available_timezones())

MANAGEMENT_TOKEN_COOKIE = "mgmt_token"

# Battery-history / estimate tuning (see /frame/battery and _battery_estimate).
BATTERY_HISTORY_MAX = 500  # ~20 days at hourly reports
BATTERY_LOG_MAX = 20000  # ~2 years at hourly reports -- see FrameConfig.battery_log
RECHARGE_JUMP_PCT = 5  # a report this much above the previous one = battery was recharged
MIN_ESTIMATE_SPAN_S = 2 * 3600  # need at least this much observed time...
MIN_ESTIMATE_DROP_PCT = 2  # ...and this much observed drop before estimating

# "Overdue" threshold multiplier: the device should check in roughly every
# refresh_interval_s; give it half again as long before flagging it.
OVERDUE_FACTOR = 1.5


def _valid_hhmm(s: str) -> bool:
    try:
        datetime.strptime(s, "%H:%M")
        return True
    except ValueError:
        return False


def _zoneinfo(name: str) -> ZoneInfo:
    """Falls back to UTC for an unrecognized zone name -- defensive only;
    api_config_save already validates against ALL_TIMEZONES before saving,
    so this only matters for a config.json hand-edited or written by an
    older version of this file."""
    try:
        return ZoneInfo(name)
    except Exception:
        return ZoneInfo("UTC")


def _quiet_hours_state(now: datetime, start_str: str, end_str: str) -> tuple[bool, datetime | None]:
    """Whether `now` falls inside the quiet-hours window, and the next
    boundary: if inside, when it ends; if outside, when it next starts.
    Handles a window that wraps past midnight (e.g. 22:00-07:00). Returns
    (False, None) for a degenerate window (start == end)."""
    sh, sm = (int(x) for x in start_str.split(":"))
    eh, em = (int(x) for x in end_str.split(":"))
    start = now.replace(hour=sh, minute=sm, second=0, microsecond=0)
    end = now.replace(hour=eh, minute=em, second=0, microsecond=0)

    if start == end:
        return False, None

    if start < end:
        # Same-day window, e.g. 13:00-15:00. End is exclusive, so being
        # exactly at `end` counts as already outside the window.
        if start <= now < end:
            return True, end
        if now < start:
            return False, start
        return False, start + timedelta(days=1)

    # Wraps midnight, e.g. 22:00-07:00.
    if now >= start:
        return True, end + timedelta(days=1)
    if now < end:
        return True, end
    return False, start


def _quiet_hours_span_s(start_str: str, end_str: str) -> int:
    """Duration of the quiet-hours window in seconds, wrap-aware."""
    sh, sm = (int(x) for x in start_str.split(":"))
    eh, em = (int(x) for x in end_str.split(":"))
    span_min = ((eh * 60 + em) - (sh * 60 + sm)) % (24 * 60)
    return span_min * 60


def _effective_refresh_interval_s(cfg: config.FrameConfig) -> int:
    """The refresh interval actually handed to the device: its configured
    value, unless quiet hours are enabled, in which case it's clamped so
    the device sleeps through the whole window instead of waking inside
    it. A device already mid-sleep when quiet hours begin can still land
    one wake inside the window (nothing server-side can prevent that
    without touching the firmware) -- but from that wake on, it's told to
    sleep exactly until the window ends."""
    if not cfg.quiet_hours_enabled:
        return cfg.refresh_interval_s
    now = datetime.now(_zoneinfo(cfg.timezone))
    in_quiet, boundary = _quiet_hours_state(now, cfg.quiet_hours_start, cfg.quiet_hours_end)
    if boundary is None:
        return cfg.refresh_interval_s
    seconds_to_boundary = max(1, int((boundary - now).total_seconds()))
    if in_quiet:
        return seconds_to_boundary
    return min(cfg.refresh_interval_s, seconds_to_boundary)


def _in_quiet_hours(cfg: config.FrameConfig) -> bool:
    """Whether quiet hours are in effect right now -- separate from
    _effective_refresh_interval_s, which only shapes what the *device* is
    told to sleep for. This instead gates photo_queue.get_current()'s
    time-based advance, since that check runs independent of the device
    (also triggered by the web UI's /api/queue, e.g. an open browser tab
    polling overnight) and would otherwise happily advance the current
    photo mid-quiet-hours on raw elapsed time alone."""
    if not cfg.quiet_hours_enabled:
        return False
    now = datetime.now(_zoneinfo(cfg.timezone))
    in_quiet, _ = _quiet_hours_state(now, cfg.quiet_hours_start, cfg.quiet_hours_end)
    return in_quiet


def _max_expected_gap_s(cfg: config.FrameConfig) -> int:
    """Longest gap between wakes the device might legitimately have --
    normally just refresh_interval_s, but quiet hours can make the real
    gap much longer, and the "overdue" check (see api_queue) shouldn't
    mistake a device quietly sleeping through the night for a dead one."""
    gap = cfg.refresh_interval_s
    if cfg.quiet_hours_enabled:
        gap = max(gap, _quiet_hours_span_s(cfg.quiet_hours_start, cfg.quiet_hours_end))
    return gap


def _touch_last_seen() -> None:
    """Records that the device just made contact. Called by every
    /frame/* route -- a handful of extra config writes per wake cycle,
    which is nothing at hourly wakes."""
    with config.locked():
        cfg = config.load()
        cfg.last_seen = time.time()
        config.save(cfg)


def _token_valid(request: Request, cfg: config.FrameConfig) -> bool:
    """No management_token configured (MANAGEMENT_TOKEN env var, see
    docker-compose.yml.example) means the whole server stays open on a
    trusted LAN, matching this project's original default. Once one's
    set, a request is authorized by either a ?token= query param (what
    the ESP32 sends on every device request, and what the manage-menu/
    share QR codes embed for a human scanning them) or the cookie
    index() sets after a valid query-param hit (so the web UI's own
    fetch()/<img> calls, which carry no query string, stay authorized
    for the rest of that browsing visit)."""
    if not cfg.management_token:
        return True
    supplied = request.query_params.get("token") or request.cookies.get(MANAGEMENT_TOKEN_COOKIE)
    return supplied is not None and supplied == cfg.management_token


def require_access_token(request: Request) -> None:
    """Dependency for every route except / and /health: the web UI's
    /api/* and every device-facing /frame/*. index() handles the
    unauthorized case itself (a friendlier HTML prompt, not a bare 401)
    since that's the one route a human is actually meant to land on with
    no token yet; the ESP32 sends its token as ?token= on every request
    it makes (see frame_client.c's build_url()), so device endpoints
    just 401 outright on a missing/wrong one. /health stays open -- it
    reveals nothing but process liveness, and gating it would break
    plain infra/uptime monitoring for no real security benefit."""
    if not _token_valid(request, config.load()):
        raise HTTPException(401, "Missing or invalid access token")


@app.get("/health")
def health() -> dict:
    return {"status": "ok"}


@app.get("/frame/config", dependencies=[Depends(require_access_token)])
def frame_config(request: Request):
    """Device-facing settings, polled by the frame alongside its
    reachability check. Always returns 200 with current settings
    (defaults if nothing's been saved yet) -- no Immich-configured gate,
    since this doubles as the "is the server up" signal. Also captures
    the device's running firmware version (X-Frame-Version header) and
    advertises the uploaded OTA image's version, so the device's update
    check costs zero extra round trips."""
    reported_version = request.headers.get("X-Frame-Version", "")
    with config.locked():
        cfg = config.load()
        cfg.last_seen = time.time()
        if cfg.stats.first_seen == 0:
            cfg.stats.first_seen = cfg.last_seen
        cfg.stats.device_wakes += 1
        if reported_version:
            if cfg.device_firmware_version and reported_version != cfg.device_firmware_version:
                cfg.stats.ota_updates_applied += 1
            cfg.device_firmware_version = reported_version
        config.save(cfg)
    return {
        "refresh_interval_s": _effective_refresh_interval_s(cfg),
        "firmware_version": cfg.firmware_available_version or None,
    }


@app.get("/", response_class=HTMLResponse)
def index(request: Request):
    cfg = config.load()
    if not _token_valid(request, cfg):
        supplied = request.query_params.get("token")
        return templates.TemplateResponse(
            "token_prompt.html", {"request": request, "wrong": supplied is not None}
        )

    response = templates.TemplateResponse(
        "index.html", {"request": request, "cfg": cfg, "timezones": ALL_TIMEZONES}
    )
    supplied = request.query_params.get("token")
    if cfg.management_token and supplied == cfg.management_token:
        # Query-param access (typically the manage-menu QR code) earns a
        # cookie so the rest of this visit's fetch()/<img> calls -- which
        # never carry the query string -- stay authorized too.
        response.set_cookie(
            MANAGEMENT_TOKEN_COOKIE, supplied, max_age=86400 * 365, httponly=True, samesite="lax"
        )
    return response


@app.get("/api/albums", dependencies=[Depends(require_access_token)])
def api_albums():
    cfg = config.load()
    if not cfg.immich_url or not cfg.immich_api_key:
        raise HTTPException(400, "Immich URL/API key not configured yet")
    try:
        albums = ImmichClient(cfg.immich_url, cfg.immich_api_key).list_albums()
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not reach Immich at {cfg.immich_url}: {e}") from e
    return [{"id": a["id"], "name": a["albumName"], "count": a.get("assetCount", 0)} for a in albums]


@app.post("/api/config", dependencies=[Depends(require_access_token)])
def api_config_save(
    album_id: str = Form(""),
    order: str = Form("sequential"),
    refresh_interval_s: int = Form(3600),
    smart_crop_faces: bool = Form(True),
    queue_target_len: int = Form(20),
    orientation: str = Form("landscape"),
    quiet_hours_enabled: bool = Form(False),
    quiet_hours_start: str = Form("22:00"),
    quiet_hours_end: str = Form("07:00"),
    timezone: str = Form("UTC"),
    firmware_update_repo_url: str = Form(""),
    firmware_board_variant: str = Form("xiao"),
    firmware_auto_update: bool = Form(False),
):
    # Immich URL/API key/Gitea token are env-var only (IMMICH_URL/
    # IMMICH_API_KEY/GITEA_FIRMWARE_TOKEN, see docker-compose.yml.example)
    # -- config.load() already applies them, and this handler doesn't touch
    # cfg.immich_url/immich_api_key/firmware_update_token at all, so
    # there's nothing here that could overwrite or clear them.
    with config.locked():
        cfg = config.load()
        if album_id != cfg.album_id:
            # A newly selected album starts clean -- the old current photo and
            # queue don't mean anything in the new album's context.
            cfg.current_asset_id = ""
            cfg.current_asset_set_at = 0.0
            cfg.queue = []
            cfg.queue_cursor = 0
            cfg.history = []
            cfg.excluded_asset_ids = []
        cfg.album_id = album_id
        cfg.order = order if order in ("sequential", "shuffle") else "sequential"
        cfg.refresh_interval_s = max(MIN_REFRESH_INTERVAL_S, min(MAX_REFRESH_INTERVAL_S, refresh_interval_s))
        cfg.smart_crop_faces = smart_crop_faces
        cfg.queue_target_len = max(MIN_QUEUE_TARGET_LEN, min(MAX_QUEUE_TARGET_LEN, queue_target_len))
        cfg.orientation = orientation if orientation in ORIENTATIONS else "landscape"
        cfg.quiet_hours_enabled = quiet_hours_enabled
        if _valid_hhmm(quiet_hours_start):
            cfg.quiet_hours_start = quiet_hours_start
        if _valid_hhmm(quiet_hours_end):
            cfg.quiet_hours_end = quiet_hours_end
        if timezone in ALL_TIMEZONES:
            cfg.timezone = timezone
        cfg.firmware_update_repo_url = firmware_update_repo_url.strip()
        cfg.firmware_board_variant = firmware_board_variant if firmware_board_variant in ("xiao", "devkit") else "xiao"
        cfg.firmware_auto_update = firmware_auto_update
        cfg.stats.config_saves += 1
        config.save(cfg)
    return {"status": "saved"}


@app.get("/api/stats", dependencies=[Depends(require_access_token)])
def api_stats():
    return config.load().stats.model_dump()


def _require_configured(cfg: config.FrameConfig) -> None:
    if not cfg.immich_url or not cfg.immich_api_key:
        raise HTTPException(400, "Immich URL/API key not configured yet")
    if not cfg.album_id:
        raise HTTPException(400, "No album configured yet")


def _list_assets(client: ImmichClient, cfg: config.FrameConfig) -> list[dict]:
    try:
        assets = client.list_album_assets(cfg.album_id)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not reach Immich at {cfg.immich_url}: {e}") from e
    if not assets:
        raise HTTPException(404, "Album has no photos")
    return assets


def _render_asset(client: ImmichClient, cfg: config.FrameConfig, asset_id: str) -> bytes:
    try:
        jpeg_bytes = client.download_asset_preview(asset_id)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not download asset from Immich: {e}") from e

    faces = None
    if cfg.smart_crop_faces:
        try:
            faces = client.get_asset_faces(asset_id)
        except httpx.HTTPError as e:
            # A faces lookup hiccup shouldn't block showing a photo at
            # all -- just fall back to a plain center-crop this cycle.
            logger.warning("Could not fetch faces for asset %s: %s", asset_id, e)

    source = Image.open(io.BytesIO(jpeg_bytes))
    return render_frame(source, faces=faces, orientation=cfg.orientation)


@app.get("/frame/image", dependencies=[Depends(require_access_token)])
def frame_image():
    """Returns the current photo. Idempotent: only actually advances to
    the next photo once refresh_interval_s has elapsed since the current
    one was set (see app/photo_queue.py) -- safe to call as often as the
    device wants, including after an unplanned reboot, without skipping
    ahead in the album."""
    _touch_last_seen()
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        if photo_queue.get_current(cfg, assets, in_quiet_hours=_in_quiet_hours(cfg)):
            config.save(cfg)

    return Response(content=_render_asset(client, cfg, cfg.current_asset_id), media_type="application/octet-stream")


@app.post("/frame/advance", dependencies=[Depends(require_access_token)])
def frame_advance():
    """Forces an immediate advance to the next photo, ignoring
    refresh_interval_s, and resets the interval clock from now. Used by
    the device's next-photo button."""
    _touch_last_seen()
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        photo_queue.advance_forced(cfg, assets)
        config.save(cfg)

    return Response(content=_render_asset(client, cfg, cfg.current_asset_id), media_type="application/octet-stream")


@app.post("/frame/back", dependencies=[Depends(require_access_token)])
def frame_back():
    """Returns to the previously-current photo (the mirror image of
    /frame/advance -- see photo_queue.back_forced()), and resets the
    interval clock from now. A no-op (still 200, current photo
    unchanged) if there's no history to go back to -- same "always
    returns something displayable" contract as /frame/advance, rather
    than erroring. Used by the device's back-photo button."""
    _touch_last_seen()
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        photo_queue.back_forced(cfg, assets)
        config.save(cfg)

    return Response(content=_render_asset(client, cfg, cfg.current_asset_id), media_type="application/octet-stream")


class BatteryReport(BaseModel):
    percent: int


@app.post("/frame/battery", dependencies=[Depends(require_access_token)])
def frame_battery(body: BatteryReport):
    """Battery level reported by the device (only when running on battery
    -- it stays silent on mains, where the charging voltage would read
    misleadingly full). Stored with a timestamp plus a per-discharge-
    cycle history that feeds the Device panel's "on battery for" and
    "estimated remaining" numbers."""
    if not 0 <= body.percent <= 100:
        raise HTTPException(400, "percent must be 0-100")
    now = time.time()
    with config.locked():
        cfg = config.load()
        cfg.stats.battery_reports += 1
        if cfg.battery_history and body.percent >= cfg.battery_history[-1][1] + RECHARGE_JUMP_PCT:
            # Percent jumped up meaningfully -- the battery was recharged
            # (or swapped). Start a fresh discharge cycle so runtime and
            # discharge-rate estimates never span a charge.
            cfg.battery_history = []
            cfg.stats.recharge_cycles += 1
        cfg.battery_history.append([now, body.percent])
        cfg.battery_history = cfg.battery_history[-BATTERY_HISTORY_MAX:]
        cfg.battery_log.append([now, body.percent])
        cfg.battery_log = cfg.battery_log[-BATTERY_LOG_MAX:]
        cfg.battery_percent = body.percent
        cfg.battery_as_of = now
        cfg.last_seen = now
        config.save(cfg)
    return {"status": "saved"}


@app.post("/api/firmware", dependencies=[Depends(require_access_token)])
def api_firmware_upload(file: UploadFile = File(...)):
    """Uploads a firmware image for OTA. The version is parsed out of the
    image itself (esp_app_desc_t) rather than trusted from a filename or
    form field, and the project name is checked so an unrelated .bin
    can't be pushed to the frame by mistake."""
    data = file.file.read()
    version = parse_app_version(data)
    firmware_path().write_bytes(data)
    with config.locked():
        cfg = config.load()
        cfg.firmware_available_version = version
        config.save(cfg)
    return {"status": "saved", "version": version, "size": len(data)}


@app.get("/frame/firmware", dependencies=[Depends(require_access_token)])
def frame_firmware():
    """The uploaded OTA image, streamed to the device (esp_https_ota).
    404 until something has been uploaded."""
    _touch_last_seen()
    path = firmware_path()
    if not path.exists():
        raise HTTPException(404, "No firmware uploaded")
    return FileResponse(path, media_type="application/octet-stream")


def _fetch_latest_release(cfg: config.FrameConfig) -> dict | None:
    try:
        return gitea_releases.fetch_latest_release(cfg.firmware_update_repo_url, cfg.firmware_update_token)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not reach Gitea at {cfg.firmware_update_repo_url}: {e}") from e


def _apply_gitea_update(cfg: config.FrameConfig) -> str:
    """Downloads the configured Gitea repo's latest release asset for this
    frame's board variant and stages it exactly like a manual
    POST /api/firmware upload would. Network I/O happens before the lock
    is taken, matching the load/mutate/save concurrency pattern used
    elsewhere (see config.locked())."""
    release = _fetch_latest_release(cfg)
    if not release:
        raise HTTPException(404, "No releases found in the configured Gitea repo")
    asset_name = gitea_releases.asset_name_for_board(cfg.firmware_board_variant)
    asset_url = release["assets"].get(asset_name)
    if not asset_url:
        raise HTTPException(404, f"Latest release has no '{asset_name}' asset")
    try:
        data = gitea_releases.download_asset(asset_url, cfg.firmware_update_token)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not download '{asset_name}' from Gitea: {e}") from e
    version = parse_app_version(data)  # same validation the manual upload path applies
    firmware_path().write_bytes(data)
    with config.locked():
        cfg = config.load()
        cfg.firmware_available_version = version
        cfg.firmware_gitea_latest_version = version
        cfg.firmware_update_checked_at = time.time()
        config.save(cfg)
    return version


@app.get("/api/firmware/check", dependencies=[Depends(require_access_token)])
def api_firmware_check():
    """Throttled check of the configured Gitea repo's latest release
    (gitea_releases.UPDATE_CHECK_INTERVAL_S) -- cheap, since it only reads
    the release's tag name, not its binaries. If firmware_auto_update is
    on and a newer version is found, applies it immediately; otherwise
    just reports it so the web UI can offer the "Update frame" button."""
    cfg = config.load()
    if not cfg.firmware_update_repo_url:
        return {"enabled": False}

    now = time.time()
    if now - cfg.firmware_update_checked_at >= gitea_releases.UPDATE_CHECK_INTERVAL_S:
        # Deliberately not updated on failure (see below) -- checked_at only
        # advances on a successful reach, so a Gitea outage gets retried
        # every poll instead of waiting out the full throttle interval.
        release = _fetch_latest_release(cfg)
        with config.locked():
            cfg = config.load()  # re-read: state may have changed since the unlocked read above
            cfg.firmware_update_checked_at = now
            if release:
                cfg.firmware_gitea_latest_version = release["version"]
            config.save(cfg)
        cfg = config.load()

    update_available = bool(
        cfg.firmware_gitea_latest_version
    ) and cfg.firmware_gitea_latest_version != cfg.firmware_available_version
    if update_available and cfg.firmware_auto_update:
        _apply_gitea_update(cfg)
        cfg = config.load()
        update_available = False

    return {
        "enabled": True,
        "latest_version": cfg.firmware_gitea_latest_version or None,
        "staged_version": cfg.firmware_available_version or None,
        "update_available": update_available,
    }


@app.post("/api/firmware/apply-latest", dependencies=[Depends(require_access_token)])
def api_firmware_apply_latest():
    """The "Update frame" button: applies the latest Gitea release right
    now, bypassing the check throttle -- this is an explicit user action,
    not a background poll."""
    cfg = config.load()
    if not cfg.firmware_update_repo_url:
        raise HTTPException(400, "No Gitea firmware repo configured")
    version = _apply_gitea_update(cfg)
    return {"status": "saved", "version": version}


def _battery_estimate_s(cfg: config.FrameConfig) -> int | None:
    """Linear remaining-time estimate from the current discharge cycle's
    observed rate, or None when there's not enough signal to be honest
    about (too little time observed, or too little drop -- a flat line
    extrapolates to garbage)."""
    hist = cfg.battery_history
    if len(hist) < 2:
        return None
    first_ts, first_pct = hist[0]
    last_ts, last_pct = hist[-1]
    span = last_ts - first_ts
    drop = first_pct - last_pct
    if span < MIN_ESTIMATE_SPAN_S or drop < MIN_ESTIMATE_DROP_PCT:
        return None
    rate = drop / span  # percent per second
    return int(last_pct / rate)


LOCATION_LINE_MAX_LEN = 14

US_STATE_ABBR = {
    "alabama": "AL", "alaska": "AK", "arizona": "AZ", "arkansas": "AR", "california": "CA",
    "colorado": "CO", "connecticut": "CT", "delaware": "DE", "florida": "FL", "georgia": "GA",
    "hawaii": "HI", "idaho": "ID", "illinois": "IL", "indiana": "IN", "iowa": "IA",
    "kansas": "KS", "kentucky": "KY", "louisiana": "LA", "maine": "ME", "maryland": "MD",
    "massachusetts": "MA", "michigan": "MI", "minnesota": "MN", "mississippi": "MS", "missouri": "MO",
    "montana": "MT", "nebraska": "NE", "nevada": "NV", "new hampshire": "NH", "new jersey": "NJ",
    "new mexico": "NM", "new york": "NY", "north carolina": "NC", "north dakota": "ND", "ohio": "OH",
    "oklahoma": "OK", "oregon": "OR", "pennsylvania": "PA", "rhode island": "RI", "south carolina": "SC",
    "south dakota": "SD", "tennessee": "TN", "texas": "TX", "utah": "UT", "vermont": "VT",
    "virginia": "VA", "washington": "WA", "west virginia": "WV", "wisconsin": "WI", "wyoming": "WY",
    "district of columbia": "DC",
}

CA_PROVINCE_ABBR = {
    "alberta": "AB", "british columbia": "BC", "manitoba": "MB", "new brunswick": "NB",
    "newfoundland and labrador": "NL", "northwest territories": "NT", "nova scotia": "NS",
    "nunavut": "NU", "ontario": "ON", "prince edward island": "PE", "quebec": "QC",
    "saskatchewan": "SK", "yukon": "YT",
}

US_COUNTRY_NAMES = {"united states", "united states of america", "usa", "us"}
CA_COUNTRY_NAMES = {"canada"}


def _truncate(text: str, max_len: int) -> str:
    if len(text) <= max_len:
        return text
    return text[: max_len - 3] + "..."


def _format_location(exif: dict) -> tuple[str, str] | None:
    """Returns (city_line, region_line), each independently truncated to
    fit its own corner-overlay line, or None if Immich hasn't geocoded
    this photo. region_line is the abbreviated state/province for US/CAN
    locations (e.g. "CA", "ON"), else the full country name."""
    city = exif.get("city")
    if not city:
        return None

    state = exif.get("state")
    country = exif.get("country")
    country_key = (country or "").strip().lower()

    if state and country_key in US_COUNTRY_NAMES:
        region = US_STATE_ABBR.get(state.strip().lower(), state)
    elif state and country_key in CA_COUNTRY_NAMES:
        region = CA_PROVINCE_ABBR.get(state.strip().lower(), state)
    elif country:
        region = country
    elif state:
        region = state
    else:
        region = ""

    return _truncate(city, LOCATION_LINE_MAX_LEN), _truncate(region, LOCATION_LINE_MAX_LEN)


def _format_taken_at(exif: dict) -> str | None:
    raw = exif.get("dateTimeOriginal")
    if not raw:
        return None
    try:
        return datetime.fromisoformat(raw.replace("Z", "+00:00")).strftime("%m/%d/%y")
    except ValueError:
        return None


@app.get("/frame/photo-info", dependencies=[Depends(require_access_token)])
def frame_photo_info():
    """Location/date-taken text for the manage-button overlay, plus the
    asset id used to build the share-QR's target URL. Read-only, same
    idempotent current-photo semantics as /frame/image -- doesn't advance
    anything."""
    _touch_last_seen()
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        if photo_queue.get_current(cfg, assets, in_quiet_hours=_in_quiet_hours(cfg)):
            config.save(cfg)

    if not cfg.current_asset_id:
        raise HTTPException(404, "No current photo")

    try:
        asset = client.get_asset(cfg.current_asset_id)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not reach Immich: {e}") from e

    exif = asset.get("exifInfo") or {}
    location = _format_location(exif)
    return {
        "asset_id": cfg.current_asset_id,
        "location_line1": location[0] if location else None,
        "location_line2": location[1] if location and location[1] else None,
        "taken_at": _format_taken_at(exif),
    }


@app.get("/frame/share/{asset_id}", dependencies=[Depends(require_access_token)])
def frame_share(asset_id: str):
    """Creates a 30-minute public Immich share link for asset_id and
    redirects to it -- what the manage overlay's bottom-left QR code
    points to (the firmware bakes ?token= into that QR the same way it
    does for the management QR, see frame_client.c's build_url()). The
    link is created lazily, when this actually gets hit (i.e. when
    someone scans it), not when the manage button was pressed, so the
    30-minute window starts when it's actually used. Also scoped to the
    photo currently showing or queued -- not any arbitrary Immich asset
    id -- as a second layer even a leaked token wouldn't bypass."""
    _touch_last_seen()
    cfg = config.load()
    _require_configured(cfg)

    if asset_id != cfg.current_asset_id and asset_id not in cfg.queue:
        raise HTTPException(404, "That photo isn't currently showing or queued on this frame")

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    try:
        share_url = client.create_share_link(asset_id, expires_in_s=1800)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not create share link: {e}") from e

    return RedirectResponse(share_url)


@app.get("/frame/face-labels", dependencies=[Depends(require_access_token)])
def frame_face_labels():
    """Named-face positions for the manage button's escalated "level 2"
    menu -- who's in the current photo, per Immich's own face
    recognition (no detection/recognition happens here, see
    app/face_labels.py). Response is a flattened, fixed-slot shape
    (name_0/x_0/y_0, name_1/x_1/y_1, ...) rather than a JSON array, so
    the device's hand-rolled parser can read it with the same flat-
    scalar helpers it already has, instead of needing a real array
    parser. Empty (count: 0) if no faces are named, or if anything about
    fetching them fails -- this is a "nice to have" addition to the
    overlay, not worth failing the whole menu over."""
    _touch_last_seen()
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        if photo_queue.get_current(cfg, assets, in_quiet_hours=_in_quiet_hours(cfg)):
            config.save(cfg)

    if not cfg.current_asset_id:
        return {"count": 0}

    try:
        faces = client.get_asset_faces(cfg.current_asset_id)
    except httpx.HTTPError as e:
        logger.warning("Could not fetch faces for asset %s: %s", cfg.current_asset_id, e)
        return {"count": 0}

    if not any((face.get("person") or {}).get("name") for face in faces):
        return {"count": 0}  # skip the extra preview download in the common no-named-faces case

    try:
        preview_bytes = client.download_asset_preview(cfg.current_asset_id)
    except httpx.HTTPError as e:
        logger.warning("Could not download asset %s for face-label mapping: %s", cfg.current_asset_id, e)
        return {"count": 0}

    labels = compute_face_labels(preview_bytes, faces, cfg.smart_crop_faces, cfg.orientation)

    result: dict[str, object] = {"count": len(labels)}
    for i, label in enumerate(labels):
        result[f"name_{i}"] = label["name"]
        result[f"x_{i}"] = label["x"]
        result[f"y_{i}"] = label["y"]
    return result


@app.get("/api/queue", dependencies=[Depends(require_access_token)])
def api_queue():
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        current_changed = photo_queue.get_current(cfg, assets, in_quiet_hours=_in_quiet_hours(cfg))
        queue_before = list(cfg.queue)
        photo_queue.sync_queue_length(cfg, assets)
        if current_changed or cfg.queue != queue_before:
            config.save(cfg)

    def entry(asset_id: str) -> dict:
        return {"id": asset_id, "thumbnail_url": f"/api/photo-thumbnail/{asset_id}"}

    now = time.time()
    return {
        "current": entry(cfg.current_asset_id) if cfg.current_asset_id else None,
        "upcoming": [entry(asset_id) for asset_id in cfg.queue],
        "device": {
            "last_seen": cfg.last_seen or None,
            "overdue": bool(cfg.last_seen and now - cfg.last_seen > _max_expected_gap_s(cfg) * OVERDUE_FACTOR),
            "firmware_version": cfg.device_firmware_version or None,
            "firmware_available": cfg.firmware_available_version or None,
            "battery": (
                {"percent": cfg.battery_percent, "as_of": cfg.battery_as_of}
                if cfg.battery_percent >= 0
                else None
            ),
            "on_battery_since": cfg.battery_history[0][0] if cfg.battery_history else None,
            "battery_estimate_s": _battery_estimate_s(cfg),
        },
    }


@app.get("/api/battery-log", dependencies=[Depends(require_access_token)])
def api_battery_log():
    cfg = config.load()
    return {"log": cfg.battery_log}


class QueueReorderRequest(BaseModel):
    queue: list[str]


@app.post("/api/queue/reorder", dependencies=[Depends(require_access_token)])
def api_queue_reorder(body: QueueReorderRequest):
    """Applies the client's requested order, tolerating drift between the
    browser's last-fetched snapshot and the server's current queue (e.g.
    a top-up/trim landed in between) instead of hard-rejecting: any ID
    the client sent that's no longer actually queued is dropped, and any
    ID the server has that the client didn't know about is appended
    rather than lost."""
    with config.locked():
        cfg = config.load()
        current_set = set(cfg.queue)
        reordered = [asset_id for asset_id in body.queue if asset_id in current_set]
        reordered += [asset_id for asset_id in cfg.queue if asset_id not in set(reordered)]
        cfg.queue = reordered
        config.save(cfg)
    return {"status": "saved"}


class QueuePromoteRequest(BaseModel):
    asset_id: str


@app.post("/api/queue/promote", dependencies=[Depends(require_access_token)])
def api_queue_promote(body: QueuePromoteRequest):
    """Moves a single photo to the front of the queue -- "Show next" in
    the web UI. Unlike /api/queue/reorder, this doesn't depend on the
    client supplying a full, exactly-current snapshot of the queue at
    all, so it can't fail due to the queue having shifted server-side
    since the browser's last fetch."""
    with config.locked():
        cfg = config.load()
        if body.asset_id not in cfg.queue:
            raise HTTPException(400, "That photo is no longer in the upcoming queue")
        cfg.queue = [body.asset_id] + [asset_id for asset_id in cfg.queue if asset_id != body.asset_id]
        config.save(cfg)
    return {"status": "saved"}


class QueueRemoveRequest(BaseModel):
    asset_id: str


@app.post("/api/queue/remove", dependencies=[Depends(require_access_token)])
def api_queue_remove(body: QueueRemoveRequest):
    """Permanently removes a photo from this frame's rotation -- "Remove"
    in the web UI, on either an upcoming card or the current photo. Does
    NOT touch Immich or the album itself; see photo_queue.remove_from_rotation()."""
    cfg = config.load()
    _require_configured(cfg)

    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    assets = _list_assets(client, cfg)

    with config.locked():
        cfg = config.load()  # re-read: state may have changed since the unlocked read above
        photo_queue.remove_from_rotation(cfg, assets, body.asset_id)
        config.save(cfg)
    return {"status": "removed"}


@app.get("/api/photo-thumbnail/{asset_id}", dependencies=[Depends(require_access_token)])
def api_photo_thumbnail(asset_id: str):
    cfg = config.load()
    _require_configured(cfg)
    client = ImmichClient(cfg.immich_url, cfg.immich_api_key)
    try:
        content, content_type = client.download_asset_thumbnail(asset_id)
    except httpx.HTTPError as e:
        raise HTTPException(502, f"Could not download thumbnail from Immich: {e}") from e
    return Response(content=content, media_type=content_type)