import assert from "node:assert/strict";
import { execFile as execFileCallback, spawn as spawnCallback } from "node:child_process";
import { randomUUID } from "node:crypto";
import { promises as fs } from "node:fs";
import path from "node:path";
import process from "node:process";
import { fileURLToPath } from "node:url";
import { promisify } from "node:util";

import { DEFAULT_CONFIG_FILE_NAME, DEFAULT_HOST_API_URL } from "./test-gateway.mjs";

const execFile = promisify(execFileCallback);
const COMPOSE_SERVICES = ["traefik", "redis", "mysql-debug", "edge-broker", "php1", "caddy"];

function composeArgs(projectName, args) {
  return ["compose", "-p", projectName, ...args];
}

async function resolveRootDir(scriptPath) {
  const cwd = process.cwd();

  try {
    await fs.access(path.join(cwd, "docker-compose.yml"));
    return cwd;
  } catch {
    return path.resolve(path.dirname(scriptPath), "..");
  }
}

async function runCommand(command, args, { cwd, allowFailure = false, stdio = "pipe" } = {}) {
  if (stdio === "inherit") {
    await new Promise((resolve, reject) => {
      const child = spawnCallback(command, args, {
        cwd,
        stdio: "inherit",
        windowsHide: true,
      });

      child.on("exit", (code) => {
        if (code === 0 || allowFailure) {
          resolve();
          return;
        }

        reject(new Error(`${command} ${args.join(" ")} failed with exit code ${code}`));
      });
      child.on("error", reject);
    });

    return { stdout: "", stderr: "", code: 0 };
  }

  try {
    const result = await execFile(command, args, {
      cwd,
      windowsHide: true,
      encoding: "utf8",
    });

    return { stdout: result.stdout, stderr: result.stderr, code: 0 };
  } catch (error) {
    if (!allowFailure) {
      throw error;
    }

    return {
      stdout: error.stdout || "",
      stderr: error.stderr || "",
      code: typeof error.code === "number" ? error.code : 1,
    };
  }
}

function normalizeBaseUrl(url) {
  return String(url || "").replace(/\/+$/, "");
}

async function waitForCondition(predicate, { timeoutMs = 30_000, intervalMs = 500, message = "Timed out" } = {}) {
  const deadline = Date.now() + timeoutMs;

  while (Date.now() < deadline) {
    if (await predicate()) {
      return;
    }

    await new Promise((resolve) => setTimeout(resolve, intervalMs));
  }

  throw new Error(message);
}

async function ensureComposeServices(rootDir, composeProject) {
  await runCommand("docker", composeArgs(composeProject, ["up", "-d", ...COMPOSE_SERVICES]), {
    cwd: rootDir,
    stdio: "inherit",
  });
}

async function waitForApiReady(baseUrl, attempts = 60) {
  const root = normalizeBaseUrl(baseUrl);
  let lastError = "API never responded";

  for (let attempt = 0; attempt < attempts; attempt += 1) {
    try {
      const response = await fetch(`${root}/ping`);
      if (response.ok) {
        return;
      }

      lastError = `Unexpected ping status ${response.status}`;
    } catch (error) {
      lastError = error instanceof Error ? error.message : String(error);
    }

    await new Promise((resolve) => setTimeout(resolve, 1000));
  }

  throw new Error(`API did not become ready at ${root}/ping: ${lastError}`);
}

function parseLastJsonLine(output) {
  const lines = String(output || "")
    .split(/\r?\n/)
    .map((line) => line.trim())
    .filter(Boolean);

  for (let index = lines.length - 1; index >= 0; index -= 1) {
    try {
      return JSON.parse(lines[index]);
    } catch {
      // Continue scanning backwards for the JSON payload.
    }
  }

  throw new Error(`Unable to parse JSON from command output:\n${output}`);
}

async function runPhpFixture(rootDir, composeProject, action, payload = null) {
  const encodedPayload = payload === null
    ? ""
    : ` ${Buffer.from(JSON.stringify(payload), "utf8").toString("base64url")}`;
  const command = `cd /var/www/html && CONFIG_DB_TARGET=debug php tests/Support/EdgeGatewayE2eFixture.php ${action}${encodedPayload}`;

  const result = await runCommand("docker", composeArgs(composeProject, [
    "exec",
    "-T",
    "php1",
    "sh",
    "-lc",
    command,
  ]), {
    cwd: rootDir,
  });

  return parseLastJsonLine(result.stdout);
}

async function apiRequest(baseUrl, method, endpoint, { token = null, body = null, headers = {} } = {}) {
  const response = await fetch(`${normalizeBaseUrl(baseUrl)}${endpoint}`, {
    method,
    headers: {
      ...(body === null ? {} : { "content-type": "application/json" }),
      ...(token ? { Authorization: `Bearer ${token}` } : {}),
      ...headers,
    },
    body: body === null ? undefined : JSON.stringify(body),
  });

  const rawBody = await response.text();
  let json = null;

  if (rawBody !== "") {
    try {
      json = JSON.parse(rawBody);
    } catch {
      json = null;
    }
  }

  if (!response.ok) {
    const message =
      json?.data?.message ||
      json?.error ||
      rawBody ||
      `HTTP ${response.status}`;
    throw new Error(`${method} ${endpoint} failed: ${message}`);
  }

  return json;
}

async function loadWebSocketImplementation() {
  if (typeof WebSocket !== "undefined") {
    return WebSocket;
  }

  const module = await import("ws");
  return module.default;
}

function onSocket(socket, eventName, handler) {
  if (typeof socket.addEventListener === "function") {
    socket.addEventListener(eventName, (event) => {
      if (eventName === "message") {
        handler(event.data);
        return;
      }

      handler(event);
    });
    return;
  }

  socket.on(eventName, handler);
}

function collectSocketMessages(socket) {
  const messages = [];

  onSocket(socket, "message", (payload) => {
    const text = typeof payload === "string"
      ? payload
      : Buffer.isBuffer(payload)
        ? payload.toString("utf8")
        : typeof payload?.toString === "function"
          ? payload.toString()
          : "";

    if (text === "") {
      return;
    }

    try {
      messages.push(JSON.parse(text));
    } catch {
      // Ignore non-JSON frames.
    }
  });

  return messages;
}

async function waitForSocketOpen(socket) {
  if (socket.readyState === 1) {
    return;
  }

  await new Promise((resolve, reject) => {
    const timeout = setTimeout(() => reject(new Error("Timed out waiting for websocket open.")), 10_000);
    const socketUrl = typeof socket.url === "string" && socket.url !== "" ? ` (${socket.url})` : "";

    const onOpen = () => {
      clearTimeout(timeout);
      resolve();
    };

    const onError = (error) => {
      clearTimeout(timeout);
      if (error instanceof Error) {
        reject(error);
        return;
      }

      const readyState = typeof socket.readyState === "number" ? socket.readyState : "unknown";
      reject(new Error(`Websocket failed to open${socketUrl}; readyState=${readyState}.`));
    };

    const onClose = (event) => {
      clearTimeout(timeout);
      const code = event && typeof event === "object" && "code" in event ? event.code : "unknown";
      const reason = event && typeof event === "object" && "reason" in event ? event.reason : "";
      reject(new Error(`Websocket closed before open${socketUrl}; code=${code} reason=${reason || "none"}.`));
    };

    onSocket(socket, "open", onOpen);
    onSocket(socket, "error", onError);
    onSocket(socket, "close", onClose);
  });
}

async function waitForSocketMessage(messages, predicate, options) {
  await waitForCondition(() => messages.some(predicate), options);
}

function buildSocketUrl(wsUrl, token) {
  const url = new URL(String(wsUrl));
  url.searchParams.set("token", token);
  return url.toString();
}

function closeSocket(socket) {
  if (!socket || typeof socket.close !== "function") {
    return;
  }

  const readyState = typeof socket.readyState === "number" ? socket.readyState : null;
  if (readyState !== null && readyState >= 2) {
    return;
  }

  socket.close();
}

function collectMessages(rows) {
  return Array.isArray(rows)
    ? rows
      .map((row) => (row && typeof row === "object" ? row.message : null))
      .filter((value) => typeof value === "string")
    : [];
}

function summarizeStreamMessages(messages, limit = 12) {
  return messages
    .slice(-limit)
    .map((message) => {
      if (!message || typeof message !== "object") {
        return null;
      }

      const summary = {
        type: message.type || "unknown",
      };

      if (message.operationId !== undefined) {
        summary.operationId = Number(message.operationId || 0);
      }

      if (message.operation && typeof message.operation === "object") {
        summary.operationStatus = message.operation.status || null;
      }

      if (message.gateway && typeof message.gateway === "object") {
        summary.gatewayStatus = message.gateway.status || null;
      }

      return summary;
    })
    .filter(Boolean);
}

async function main() {
  const scriptPath = fileURLToPath(import.meta.url);
  const rootDir = await resolveRootDir(scriptPath);
  const runId = randomUUID().slice(0, 8);
  const containerName = `truckwash-edge-e2e-${runId}`;
  const configDir = path.join(rootDir, ".tmp", "edge-gateway-e2e", runId);
  const configFilePath = path.join(configDir, DEFAULT_CONFIG_FILE_NAME);
  const baseUrl = process.env.EDGE_GATEWAY_E2E_BASE_URL || DEFAULT_HOST_API_URL;
  const composeProject =
    process.env.EDGE_GATEWAY_E2E_COMPOSE_PROJECT
    || path.basename(rootDir);

  let fixture = null;
  let gatewayId = null;
  let streamSocket = null;
  let shellSocket = null;

  try {
    await ensureComposeServices(rootDir, composeProject);
    await waitForApiReady(baseUrl);

    fixture = await runPhpFixture(rootDir, composeProject, "create");
    const authToken = String(fixture.auth_token || "");
    const departmentId = Number(fixture.department_id || 0);

    assert.ok(authToken !== "", "Fixture helper did not return an auth token.");
    assert.ok(departmentId > 0, "Fixture helper did not return a department id.");

    const installTokenResponse = await apiRequest(baseUrl, "POST", "/edge-gateways/install-token", {
      token: authToken,
      body: {
        department_id: departmentId,
        label: `Edge Gateway E2E ${runId}`,
      },
    });
    const installToken = String(installTokenResponse?.data?.token || "");
    assert.ok(installToken !== "", "Install token creation did not return a token.");

    await runCommand(process.execPath, [
      "scripts/test-gateway.mjs",
      "start",
      "--install-token",
      installToken,
      "--container-name",
      containerName,
      "--config-dir",
      configDir,
      "--heartbeat-seconds",
      "3",
      "--skip-compose-up",
    ], {
      cwd: rootDir,
      stdio: "inherit",
    });

    await waitForCondition(
      async () => {
        try {
          await fs.access(configFilePath);
          return true;
        } catch {
          return false;
        }
      },
      { message: `Gateway config file was not created at ${configFilePath}` }
    );

    const config = JSON.parse(await fs.readFile(configFilePath, "utf8"));
    gatewayId = Number(config.gatewayId || 0);
    assert.ok(gatewayId > 0, "Gateway config did not include a gateway id.");

    await waitForCondition(
      async () => {
        const result = await runCommand("docker", [
          "exec",
          containerName,
          "test",
          "-f",
          "/opt/truckwash-edge-agent/runtime/last-heartbeat-ok.txt",
        ], {
          allowFailure: true,
        });

        return result.code === 0;
      },
      {
        timeoutMs: 60_000,
        message: "Gateway never wrote the successful heartbeat marker.",
      }
    );

    await waitForCondition(
      async () => {
        const detail = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}`, {
          token: authToken,
        });

        return detail?.data?.status === "ONLINE"
          && Object.keys(detail?.data?.metadata?.system_metrics || {}).length > 0;
      },
      {
        timeoutMs: 60_000,
        message: "Gateway detail never transitioned to ONLINE with fresh system metrics after install.",
      }
    );

    await waitForCondition(
      async () => {
        const detail = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}`, {
          token: authToken,
        });

        return Boolean(
          detail?.data?.channel_status?.broker?.connected
          || detail?.data?.metadata?.broker_connected
        );
      },
      {
        timeoutMs: 90_000,
        message: "Gateway never established a live broker connection after install.",
      }
    );

    const WebSocketImpl = await loadWebSocketImplementation();
    const streamSession = await apiRequest(baseUrl, "POST", `/edge-gateways/${gatewayId}/stream-session`, {
      token: authToken,
      body: {
        scopes: ["overview", "tasks", "logs", "statistics"],
      },
    });
    const streamWsUrl = buildSocketUrl(String(streamSession?.data?.ws_url || ""), String(streamSession?.data?.token || ""));
    streamSocket = new WebSocketImpl(streamWsUrl);
    const streamMessages = collectSocketMessages(streamSocket);

    await waitForSocketOpen(streamSocket);
    await waitForSocketMessage(
      streamMessages,
      (message) => message?.type === "gateway.stream.ready",
      { timeoutMs: 15_000, message: "Gateway stream never became ready." }
    );

    const readyMessage = streamMessages.find((message) => message?.type === "gateway.stream.ready");
    assert.equal(
      Boolean(readyMessage?.connected),
      true,
      "Gateway stream became ready before the broker reported the gateway as connected."
    );

    const operationResponse = await apiRequest(baseUrl, "POST", `/edge-gateways/${gatewayId}/operations`, {
      token: authToken,
      body: {
        type: "DISCOVERY",
        request: {
          inventory: [{
            device_id: `edge-e2e-${runId}`,
            local_ip: "10.70.80.90",
            model: "TruckWash Edge E2E",
            channel_count: 1,
            online: true,
            capabilities: {
              gateway_management_v2: true,
            },
            metadata: {
              hostname: `edge-e2e-${runId}`,
            },
          }],
        },
      },
    });
    const operationId = Number(operationResponse?.data?.operation?.id || 0);
    assert.ok(operationId > 0, "Operation creation did not return an operation id.");

    try {
      await waitForSocketMessage(
        streamMessages,
        (message) => message?.type === "task.updated" && Number(message?.operationId || 0) === operationId,
        { timeoutMs: 180_000, message: "Live gateway stream never emitted task.updated for the queued operation." }
      );
    } catch (error) {
      let operationSnapshot = null;
      try {
        const operations = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}/operations`, {
          token: authToken,
        });
        operationSnapshot = Array.isArray(operations?.data)
          ? operations.data.find((item) => Number(item?.id || 0) === operationId) || null
          : null;
      } catch {
        operationSnapshot = null;
      }

      const diagnostic = [
        error instanceof Error ? error.message : String(error),
        `Recent stream messages: ${JSON.stringify(summarizeStreamMessages(streamMessages))}`,
        `Operation snapshot: ${JSON.stringify(operationSnapshot)}`,
      ].join("\n");
      throw new Error(diagnostic);
    }

    await waitForCondition(
      async () => {
        const operations = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}/operations`, {
          token: authToken,
        });

        const operation = Array.isArray(operations?.data)
          ? operations.data.find((item) => Number(item?.id || 0) === operationId)
          : null;

        return operation?.status === "COMPLETED";
      },
      { timeoutMs: 180_000, message: "Gateway operation never completed through the live agent." }
    );

    await waitForSocketMessage(
      streamMessages,
      (message) => message?.type === "gateway.telemetry" || message?.type === "stats.updated",
      { timeoutMs: 15_000, message: "Live gateway stream never emitted telemetry or statistics updates." }
    );

    await waitForCondition(
      async () => {
        const logs = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}/logs`, {
          token: authToken,
        });

        const timeline = Array.isArray(logs?.data?.entries)
          ? logs.data.entries
          : (Array.isArray(logs?.data?.timeline) ? logs.data.timeline : []);

        return timeline.some((entry) => {
          const nestedEntry = entry?.entry && typeof entry.entry === "object" ? entry.entry : null;
          const directOperationId = Number(nestedEntry?.operation_id || 0);
          const contextualOperationId = Number(nestedEntry?.context?.operation_id || 0);

          return directOperationId === operationId || contextualOperationId === operationId;
        });
      },
      { timeoutMs: 30_000, message: "Gateway logs page never reflected the live operation timeline." }
    );

    const statistics = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}/statistics`, {
      token: authToken,
    });
    assert.ok(
      Object.keys(statistics?.data?.system_metrics || {}).length > 0,
      "Gateway statistics page did not expose system metrics after live telemetry."
    );

    const shellSession = await apiRequest(baseUrl, "POST", `/edge-gateways/${gatewayId}/shell-sessions`, {
      token: authToken,
      body: {
        reason: "Edge gateway E2E shell validation",
        cwd: "/opt/truckwash-edge-agent",
        cols: 120,
        rows: 40,
      },
    });
    const shellWsUrl = buildSocketUrl(String(shellSession?.data?.ws_url || ""), String(shellSession?.data?.token || ""));
    shellSocket = new WebSocketImpl(shellWsUrl);
    const shellMessages = collectSocketMessages(shellSocket);

    await waitForSocketOpen(shellSocket);
    await waitForSocketMessage(
      shellMessages,
      (message) => message?.type === "opened",
      { timeoutMs: 20_000, message: "Browser shell never opened against the live gateway." }
    );

    shellSocket.send(JSON.stringify({
      type: "input",
      data: "printf 'edge-e2e-shell\\n'; exit\n",
    }));

    await waitForSocketMessage(
      shellMessages,
      (message) => message?.type === "output" && String(message?.data || "").includes("edge-e2e-shell"),
      { timeoutMs: 20_000, message: "Browser shell never returned the expected command output." }
    );

    await waitForSocketMessage(
      shellMessages,
      (message) => message?.type === "closed",
      { timeoutMs: 20_000, message: "Browser shell never closed cleanly." }
    );

    const logsAfterShell = await apiRequest(baseUrl, "GET", `/edge-gateways/${gatewayId}/logs`, {
      token: authToken,
    });
    const shellTranscripts = Array.isArray(logsAfterShell?.data?.shell_sessions)
      ? logsAfterShell.data.shell_sessions.map((session) => String(session?.transcript || ""))
      : [];

    assert.ok(
      shellTranscripts.some((transcript) => transcript.includes("edge-e2e-shell")),
      "Gateway logs page did not persist the shell transcript."
    );

    const timelineMessages = collectMessages(logsAfterShell?.data?.timeline || []);
    assert.ok(
      timelineMessages.includes("GATEWAY_SHELL_SESSION_CLOSED"),
      "Gateway logs page did not include the shell close audit event."
    );

    process.stdout.write("Edge gateway E2E smoke completed successfully.\n");
  } finally {
    closeSocket(shellSocket);
    closeSocket(streamSocket);

    await runCommand(process.execPath, [
      "scripts/test-gateway.mjs",
      "stop",
      "--container-name",
      containerName,
    ], {
      cwd: rootDir,
      allowFailure: true,
    }).catch(() => {});

    if (gatewayId !== null && fixture?.auth_token) {
      await apiRequest(baseUrl, "DELETE", `/edge-gateways/${gatewayId}`, {
        token: String(fixture.auth_token),
      }).catch(() => {});
    }

    if (fixture !== null) {
      await runPhpFixture(rootDir, composeProject, "cleanup", fixture).catch(() => {});
    }

    await fs.rm(configDir, { recursive: true, force: true }).catch(() => {});
  }
}

main().catch((error) => {
  process.stderr.write(`${error instanceof Error ? error.message : String(error)}\n`);
  process.exitCode = 1;
});