const crypto = require("crypto");

async function createPlugin(ctx) {
  const tickets = new Map();

  return {
    async execute(action, input) {
      if (action === "issueAccess") {
        return issueAccess(ctx, tickets, input || {});
      }
      if (action === "verifyAccess") {
        return verifyAccess(tickets, input || {});
      }
      if (action === "revokeOwner") {
        return revokeOwner(tickets, input || {});
      }
      if (action === "serviceStart") {
        return controlService(ctx, true);
      }
      if (action === "serviceStop") {
        return controlService(ctx, false);
      }
      if (action === "ensureSdrPath") {
        return ensureSdrPath(ctx);
      }
      throw new Error(`Unknown action: ${action}`);
    },
    async getStatus() {
      pruneExpired(tickets);
      return {
        activeTickets: tickets.size
      };
    },
    async health() {
      return { ok: true };
    }
  };
}

function issueAccess(ctx, tickets, input) {
  pruneExpired(tickets);
  const userId = String(input.userId || "").trim();
  const ownerUserId = String(input.ownerUserId || "").trim();
  if (!userId || !ownerUserId || userId !== ownerUserId) {
    throw new Error("OpenWebRX Zugriff nur fuer aktiven Besitzer");
  }
  const ttlSec = Number(ctx.getSetting("ticketTtlSec", ctx.env.OPENWEBRX_TICKET_TTL_SEC || 3600));
  const ttlExpiresAtMs = Date.now() + Math.max(10, ttlSec) * 1000;
  const stationEndsAtMs = Date.parse(String(input.stationEndsAt || ""));
  const expiresAtMs = Number.isFinite(stationEndsAtMs)
    ? Math.min(ttlExpiresAtMs, stationEndsAtMs)
    : ttlExpiresAtMs;
  const ticket = crypto.randomBytes(24).toString("base64url");
  tickets.set(ticket, {
    userId,
    ownerUserId,
    createdAt: new Date().toISOString(),
    expiresAtMs
  });
  const openWebRxPath = String(ctx.getSetting("upstreamPath", ctx.env.OPENWEBRX_PATH || "/openwebrx/")).trim() || "/openwebrx/";
  const separator = openWebRxPath.includes("?") ? "&" : "?";
  const iframeUrl = `${openWebRxPath}${separator}ticket=${encodeURIComponent(ticket)}`;
  return {
    ticket,
    expiresAt: new Date(expiresAtMs).toISOString(),
    iframeUrl,
    userId
  };
}

function verifyAccess(tickets, input) {
  pruneExpired(tickets);
  const ticket = String(input.ticket || "").trim();
  if (!ticket || !tickets.has(ticket)) {
    return { ok: false };
  }
  const entry = tickets.get(ticket);
  if (!entry || entry.expiresAtMs <= Date.now()) {
    tickets.delete(ticket);
    return { ok: false };
  }
  return {
    ok: true,
    userId: entry.userId,
    ownerUserId: entry.ownerUserId,
    expiresAt: new Date(entry.expiresAtMs).toISOString()
  };
}

function revokeOwner(tickets, input) {
  const ownerUserId = String(input.ownerUserId || "").trim();
  if (!ownerUserId) {
    return { ok: true, revoked: 0 };
  }
  let revoked = 0;
  for (const [ticket, entry] of tickets.entries()) {
    if (entry.ownerUserId === ownerUserId) {
      tickets.delete(ticket);
      revoked += 1;
    }
  }
  return { ok: true, revoked };
}

async function controlService(ctx, start) {
  const command = String(ctx.getSetting(start ? "startCommand" : "stopCommand", start ? (ctx.env.OPENWEBRX_START_CMD || "") : (ctx.env.OPENWEBRX_STOP_CMD || ""))).trim();
  if (!command) {
    return { ok: true, skipped: true, message: "Kein OpenWebRX Service-Kommando gesetzt" };
  }
  const simulate = typeof ctx.simulateHardware === "boolean"
    ? ctx.simulateHardware
    : !(process.platform === "linux" || String(ctx.env.ALLOW_NON_LINUX_CMDS || "false") === "true");
  if (simulate) {
    return {
      ok: true,
      skipped: true,
      message: `OpenWebRX ${start ? "start" : "stop"} simuliert (${ctx.execMode || "dev"})`
    };
  }
  const timeoutMs = Number(ctx.getSetting("timeoutMs", ctx.env.OPENWEBRX_CTRL_TIMEOUT_MS || 20000));
  const result = await ctx.commandRunner(command, { timeoutMs });
  if (!result.ok) {
    throw new Error(result.stderr || result.error || `OpenWebRX ${start ? "start" : "stop"} failed`);
  }
  return { ok: true, message: `OpenWebRX ${start ? "gestartet" : "gestoppt"}` };
}

async function ensureSdrPath(ctx) {
  const command = String(ctx.getSetting("ensureSdrCommand", ctx.env.OPENWEBRX_ENSURE_SDR_CMD || "")).trim();
  if (!command) {
    return { ok: true, skipped: true, message: "Kein OpenWebRX SDR-Pfad-Kommando gesetzt" };
  }
  const simulate = typeof ctx.simulateHardware === "boolean"
    ? ctx.simulateHardware
    : !(process.platform === "linux" || String(ctx.env.ALLOW_NON_LINUX_CMDS || "false") === "true");
  if (simulate) {
    return {
      ok: true,
      skipped: true,
      message: `OpenWebRX SDR-Pfad nur simuliert (${ctx.execMode || "dev"})`
    };
  }
  const timeoutMs = Number(ctx.getSetting("timeoutMs", ctx.env.OPENWEBRX_CTRL_TIMEOUT_MS || 20000));
  const result = await ctx.commandRunner(command, { timeoutMs });
  if (!result.ok) {
    throw new Error(result.stderr || result.error || "OpenWebRX SDR-Pfad setzen fehlgeschlagen");
  }
  return { ok: true, message: "OpenWebRX SDR-Pfad auf SDR gesetzt" };
}

function pruneExpired(tickets) {
  const now = Date.now();
  for (const [ticket, entry] of tickets.entries()) {
    if (!entry || entry.expiresAtMs <= now) {
      tickets.delete(ticket);
    }
  }
}

module.exports = {
  createPlugin
};