"""Фейковый хаб для тестов агента: маршруты /agent/* в памяти."""
import base64
import hashlib
import json
import re
import socket
import threading
import time
from datetime import datetime
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer


MAX_PAGES = 50
MAX_FILE = 10 * 1024 * 1024


def check_pages(command, command_id, pages):
    """Форма пачки как в stage.accept/_check хаба: (код, тело ошибки) или None. 422 — {"error", "detail"}."""
    def bad(detail, status=422, error="bad_pages"):
        return status, {"error": error, "detail": detail}

    if isinstance(command_id, bool) or not isinstance(command_id, int):
        return bad("command_id — целое", error="bad_request")
    if not isinstance(pages, list) or not pages or len(pages) > MAX_PAGES:
        return bad("pages — список от 1 до %d страниц" % MAX_PAGES)
    if command is None:
        return bad("command %s" % command_id, 404, "not_found")
    if command["type"] != "wiki_sync" or command["status"] != "claimed":
        return bad("команда %s не выдана агенту как wiki_sync" % command_id, 409, "not_claimed")
    limits = {"code": 200, "title": 1000, "url": 4000, "parent_code": 200, "eva_id": 200}
    for i, page in enumerate(pages, 1):
        if not isinstance(page, dict):
            return bad("страница %d: не объект" % i)
        code = page.get("code")
        if not isinstance(code, str) or not code.strip() or len(code) > limits["code"]:
            return bad("страница %d: code" % i)
        for key, required in (("title", True), ("parent_code", False), ("url", False)):
            v = page.get(key)
            if v is None and not required:
                continue
            if not isinstance(v, str) or (required and not v.strip()) or len(v) > limits[key]:
                return bad("%s: %s" % (code, key))
        if not isinstance(page.get("html"), str):
            return bad("%s: html" % code)
        o = page.get("orderno")
        if o is not None and (not isinstance(o, int) or isinstance(o, bool)):
            return bad("%s: orderno" % code)
        e = page.get("eva_id")
        if e is not None and (not isinstance(e, str) or len(e) > limits["eva_id"]):
            return bad("%s: eva_id" % code)
        att, links = page.get("attachments") or [], page.get("links") or []
        if not isinstance(att, list) or not all(
                isinstance(a, dict) and isinstance(a.get("ref"), str) and isinstance(a.get("url"), str)
                and isinstance(a.get("name") or "", str) for a in att):
            return bad("%s: attachments" % code)
        if not isinstance(links, list) or not all(
                isinstance(l, dict) and isinstance(l.get("ref"), str) and isinstance(l.get("code"), str)
                for l in links):
            return bad("%s: links" % code)
    return None


def check_versions(command, command_id, versions):
    """Форма пачки версий как в приёме версий хаба (change wiki-history): (код, тело ошибки) или None."""
    def bad(detail, status=422, error="bad_versions"):
        return status, {"error": error, "detail": detail}

    if isinstance(command_id, bool) or not isinstance(command_id, int):
        return bad("command_id — целое", error="bad_request")
    if not isinstance(versions, list) or not versions or len(versions) > MAX_PAGES:
        return bad("versions — список от 1 до %d версий" % MAX_PAGES)
    if command is None:
        return bad("command %s" % command_id, 404, "not_found")
    if command["type"] != "wiki_sync" or command["status"] != "claimed":
        return bad("команда %s не выдана агенту как wiki_sync" % command_id, 409, "not_claimed")
    for i, v in enumerate(versions, 1):
        code = v.get("code") if isinstance(v, dict) else None
        if not isinstance(code, str) or not code.strip():
            return bad("версия %d: code" % i)
        page = v.get("page_code")
        if not isinstance(page, str) or not page.strip():
            return bad("%s: page_code" % code)
        try:
            ok = isinstance(v.get("created_at"), str) and datetime.fromisoformat(v["created_at"]).tzinfo is not None
        except ValueError:
            ok = False
        if not ok:
            return bad("%s: created_at" % code)
        a = v.get("author")
        if not isinstance(a, dict) or not all(a.get(k) is None or isinstance(a.get(k), str) for k in ("login", "name")):
            return bad("%s: author" % code)
        if not isinstance(v.get("html"), str):
            return bad("%s: html" % code)
        att, links = v.get("attachments"), v.get("links")
        if not isinstance(att, list) or not all(
                isinstance(x, dict) and isinstance(x.get("ref"), str) and isinstance(x.get("url"), str)
                and isinstance(x.get("name") or "", str) for x in att):
            return bad("%s: attachments" % code)
        if not isinstance(links, list) or not all(
                isinstance(x, dict) and isinstance(x.get("ref"), str) and isinstance(x.get("code"), str)
                for x in links):
            return bad("%s: links" % code)
    return None


class FakeHub:
    token = "agent-token"

    def __init__(self, settings):
        self.settings = dict(settings)
        self.queue = []
        self.commands = {}
        self.results = {}
        self.claims = 0
        self.claim_bodies = []
        self.fail_results = 0
        self.reject_results = {}
        self.in_flight = None
        self.release = None             # {"version", "sha256", "content"} — опубликованная версия агента
        self.release_requests = 0
        self.files = {}                 # sha256 → содержимое (хранилище файлов хаба)
        self.file_requests = 0
        self.pages = []                 # тела POST /agent/wiki/pages
        self.reject_pages = None        # (код, тело) — ответ на /agent/wiki/pages ошибкой
        self.versions = []              # тела принятых POST /agent/wiki/versions
        self.reject_versions = None     # (код, тело) — ответ на /agent/wiki/versions ошибкой
        self.fail_versions = 0          # сколько ближайших /agent/wiki/versions ответить 503
        self.wiki_posts = []            # пути POST /agent/wiki/pages|versions по порядку (и отклонённых)
        self.claim_wait = 0             # с: при пустой очереди держать claim, как хаб
        self.uploaded = []              # содержимое, присланное агентом POST /agent/files
        self.reject_files = None        # (код, тело) — ответ на POST /agent/files ошибкой; "drop" — оборвать без ответа
        self.lock = threading.Lock()
        hub = self

        class Handler(BaseHTTPRequestHandler):
            def log_message(self, *a):
                pass

            def do_GET(self):
                hub.handle(self, "GET")

            def do_POST(self):
                hub.handle(self, "POST")

        self.server = ThreadingHTTPServer(("127.0.0.1", 0), Handler)
        threading.Thread(target=self.server.serve_forever, daemon=True).start()

    @property
    def base_url(self):
        return "http://127.0.0.1:%d" % self.server.server_port

    def stop(self):
        self.server.shutdown()
        self.server.server_close()

    def enqueue(self, ctype, params, pause=0):
        cid = len(self.commands) + 1
        self.commands[cid] = {"id": cid, "type": ctype, "params": params, "pause_seconds": pause, "status": "queued"}
        self.queue.append(cid)
        return cid

    def put_file(self, data):
        sha = hashlib.sha256(data).hexdigest()
        self.files[sha] = data
        return sha

    def _issued(self, c):
        return dict(c["params"])

    def _release_ref(self):
        r = self.release
        return {"version": r["version"], "sha256": r["sha256"]} if r else None

    def handle(self, h, method):
        length = int(h.headers.get("Content-Length") or 0)
        body = json.loads(h.rfile.read(length).decode("utf-8")) if length else {}
        if h.headers.get("Authorization") != "Bearer " + self.token:
            return self._send(h, 401, {"error": "unauthorized"})
        path = h.path.split("?")[0]
        if path == "/agent/files" and method == "POST" and self.reject_files == "drop":
            h.close_connection = True
            h.connection.shutdown(socket.SHUT_RDWR)
            return
        if path == "/agent/claim" and self.claim_wait:
            end = time.monotonic() + self.claim_wait
            while time.monotonic() < end:           # ждать без блокировки: другие запросы (enqueue) проходят
                with self.lock:
                    if self.queue:
                        break
                time.sleep(0.05)
        with self.lock:
            code, payload = self.route(method, path, body)
        self._send(h, code, payload)

    def _send(self, h, code, payload):
        data = json.dumps(payload, ensure_ascii=False).encode("utf-8")
        h.send_response(code)
        h.send_header("Content-Type", "application/json")
        h.send_header("Content-Length", str(len(data)))
        h.end_headers()
        h.wfile.write(data)

    def route(self, method, path, body):
        if path == "/agent/claim":
            self.claim_bodies.append(body or {})
            self.claims += 1
            if self.in_flight and self.commands[self.in_flight]["status"] == "claimed":
                return 200, {"command": None, "settings_version": self.settings["settings_version"],
                             "agent_release": self._release_ref()}
            if not self.queue:
                return 200, {"command": None, "settings_version": self.settings["settings_version"],
                             "agent_release": self._release_ref()}
            cid = self.queue.pop(0)
            self.commands[cid]["status"] = "claimed"
            self.in_flight = cid
            c = self.commands[cid]
            return 200, {"command": {"id": cid, "type": c["type"], "params": self._issued(c), "pause_seconds": c["pause_seconds"]},
                         "settings_version": self.settings["settings_version"], "agent_release": self._release_ref()}
        if path == "/agent/release":
            self.release_requests += 1
            return (200, self.release) if self.release else (404, {"error": "no_release"})
        if path == "/agent/settings":
            return 200, self.settings
        if path == "/agent/wiki/versions" and method == "POST":
            self.wiki_posts.append(path)
            if self.fail_versions > 0:
                self.fail_versions -= 1
                return 503, {"error": "busy"}
            if self.reject_versions:
                return self.reject_versions
            cid = body.get("command_id")
            bad = check_versions(self.commands.get(cid) if isinstance(cid, int) else None, cid, body.get("versions"))
            if bad:
                return bad
            self.versions.append(body)
            return 200, {"accepted": len(body.get("versions") or [])}
        if path == "/agent/wiki/pages" and method == "POST":
            self.wiki_posts.append(path)
            if self.reject_pages:
                return self.reject_pages
            cid = body.get("command_id")
            bad = check_pages(self.commands.get(cid) if isinstance(cid, int) else None, cid, body.get("pages"))
            if bad:
                return bad
            self.pages.append(body)
            return 200, {"accepted": len(body.get("pages") or [])}
        if path == "/agent/files" and method == "POST":
            if self.reject_files:
                return self.reject_files
            data = base64.b64decode(body.get("content") or "", validate=True)
            if len(data) > MAX_FILE:                # как files.put хаба; пустой файл от агента принимается (allow_empty)
                return 413, {"error": "too_large", "detail": "файл больше %d байт (%d)" % (MAX_FILE, len(data))}
            self.uploaded.append(data)
            return 200, {"file": self.put_file(data), "size": len(data)}
        m = re.match(r"^/agent/commands/(\d+)$", path)
        if m:
            c = self.commands.get(int(m.group(1)))
            return (200, dict(c, params=self._issued(c))) if c else (404, {"error": "not_found"})
        m = re.match(r"^/agent/commands/(\d+)/result$", path)
        if m:
            cid = int(m.group(1))
            if self.fail_results > 0:
                self.fail_results -= 1
                return 503, {"error": "busy"}
            if cid in self.reject_results:
                return self.reject_results[cid], {"error": "rejected"}
            if cid not in self.commands:
                return 404, {"error": "not_found"}
            if self.commands[cid]["status"] in ("done", "failed", "cancelled"):
                return 200, self.commands[cid]      # терминальный статус не перезаписывается (как живой хаб)
            self.results[cid] = body
            self.commands[cid]["status"] = body.get("status")
            if self.in_flight == cid:
                self.in_flight = None
            return 200, self.commands[cid]
        return 404, {"error": "not_found", "detail": path}