"""Hardened adapter over the MIT-0 guooscar 1.2.0 device/upload methods.

No UI, scheduler, renderer, environment lookup, or constructor cloud calls.
Never retry a write; a timeout may have occurred after cloud acceptance.
"""

import threading
import time
from collections import deque
from urllib.parse import quote

import requests

from pigway_frame_flow.errors import ErrorCode as E
from pigway_frame_flow.errors import FlowError
from vendor import guooscar_protocol

BASE_URL = "https://api.kokonna.art/openapi"


class SafeTransport:
    def __init__(self, key, session=None):
        self.key = key
        self.session = session or requests.Session()
        self.calls: deque[float] = deque()
        self.lock = threading.Lock()

    def request(self, endpoint, payload=None, write=False, binary=False):
        if not self.key:
            raise FlowError(E.CONFIG_REQUIRED, "KoKonna configuration required", 503)
        with self.lock:
            current = time.monotonic()
            while self.calls and current - self.calls[0] >= 60:
                self.calls.popleft()
            # Reserve capacity beneath the official 20/minute ceiling.
            if len(self.calls) >= 18:
                raise FlowError(E.RATE_LIMITED, "Device request budget exhausted", 429)
            self.calls.append(current)
        url = BASE_URL + endpoint
        try:
            response = self.session.request(
                "GET" if binary else "POST",
                url,
                headers={}
                if binary
                else {
                    "Authorization": "Bearer " + self.key,
                    "Content-Type": "application/json",
                },
                json=None if binary else payload or {},
                timeout=(5, 120 if endpoint == "/upload" else 30),
                allow_redirects=False,
            )
        except requests.RequestException:
            raise FlowError(
                E.WRITE_RESULT_UNKNOWN if write else E.CLOUD_UNAVAILABLE,
                "Cloud write outcome is unknown"
                if write
                else "Device cloud is unavailable",
                502,
            ) from None
        if response.status_code != 200:
            code = (
                E.RATE_LIMITED
                if response.status_code == 429
                else (
                    E.WRITE_RESULT_UNKNOWN
                    if write and response.status_code >= 500
                    else E.CLOUD_UNAVAILABLE
                )
            )
            raise FlowError(
                code,
                "Device cloud request failed",
                429 if code == E.RATE_LIMITED else 502,
            )
        if binary:
            if len(response.content) > 20 * 1024 * 1024:
                raise FlowError(E.INVALID_REQUEST, "Cloud image exceeds size limit")
            return response.content
        try:
            value = response.json()
            if not isinstance(value, dict):
                raise ValueError()
            # Cloud errors may echo credentials: never return raw messages.
            if value.get("success") is False or (
                "message" in value and "id" not in value
            ):
                raise ValueError()
            return value
        except ValueError:
            raise FlowError(
                E.WRITE_RESULT_UNKNOWN if write else E.CLOUD_UNAVAILABLE,
                "Invalid device cloud response",
                502,
            ) from None


class KokonnaClient:
    def __init__(self, key, write_enabled=False, session=None):
        self.transport = SafeTransport(key, session)
        self.write_enabled = write_enabled

    def guard(self):
        if not self.write_enabled:
            raise FlowError(
                E.WRITE_DISABLED,
                "Real device writes require explicit authorization",
                403,
            )

    def get_device(self):
        return guooscar_protocol.device(self.transport)

    def list_images(self):
        return self.transport.request("/listImages", {})

    def upload(self, path, name):
        self.guard()
        value = guooscar_protocol.upload(self.transport, path.read_bytes(), name)
        if not isinstance(value.get("id"), int) or value["id"] <= 0:
            raise FlowError(E.WRITE_RESULT_UNKNOWN, "Upload ID not confirmed", 502)
        return value["id"]

    def display(self, image_id):
        self.guard()
        return self.transport.request(
            "/displayImageById", {"imageId": image_id}, write=True
        )

    def delete(self, image_id):
        self.guard()
        return self.transport.request("/deleteImage", {"imageId": image_id}, write=True)

    def download(self, image_id):
        return self.transport.request(
            f"/image/{quote(self.transport.key, safe='')}/{image_id}", binary=True
        )

    def display_by_name(self, name):
        self.guard()
        return self.transport.request(
            "/displayImageByName", {"imageName": name}, write=True
        )