'use strict';

// dashboardAPI nodeClass — passive HTTP-emitter adapter.
//
// Does NOT extend BaseNodeAdapter: dashboardAPI has no generalFunctions
// config JSON, no Port-0/1 telemetry stream, no parent registration, no
// tick or status loop. It just listens for `child.register` and emits one
// Grafana upsert HTTP request per dashboard. See OPEN_QUESTIONS.md
// (2026-05-10) for the rationale.

const { configManager, createRegistry } = require('generalFunctions');
const DashboardApi = require('./specificClass');
const commands = require('./commands');

class nodeClass {
  constructor(uiConfig, RED, nodeInstance, nameOfNode) {
    this.node = nodeInstance;
    this.RED = RED;
    this.name = nameOfNode;

    this.config = this._buildConfig(uiConfig);
    this.source = new DashboardApi(this.config);
    this.node.source = this.source;

    this._commands = createRegistry(commands, { logger: this.source?.logger });

    this._attachInputHandler();
    this._attachCloseHandler();
    this._attachLifecycleHook();
  }

  // Subscribe to Node-RED's `flows:started` event to cache the deploy diff so
  // the child.register handler can decide whether *this* dashboardAPI's
  // subtree was affected. Predicate documented in Gitea issue #32 spike.
  _attachLifecycleHook() {
    if (!this.RED?.events?.on) return;
    this._flowsStartedListener = (payload) => {
      const diff = payload?.diff || null;
      this.source.lastFlowsStartedDiff = diff;
      this.source.lastFlowsStartedAt = Date.now();
      if (this.source?.logger?.debug) {
        const summary = diff
          ? Object.fromEntries(
              ['added', 'changed', 'removed', 'rewired', 'linked', 'flowChanged']
                .map((k) => [k, (diff[k] || []).length])
            )
          : null;
        this.source.logger.debug({ event: 'flows:started', type: payload?.type, diff: summary });
      }
    };
    this.RED.events.on('flows:started', this._flowsStartedListener);
  }

  _buildConfig(uiConfig) {
    const cfgMgr = new configManager();
    // Credentials block (Node-RED encrypts at rest in flow_cred.json). Legacy
    // installs may still carry bearerToken on uiConfig — fall back with a
    // one-time deprecation warning so the user knows to re-save.
    const credentialToken = this.node?.credentials?.bearerToken || '';
    const legacyToken = uiConfig.bearerToken || '';
    if (!credentialToken && legacyToken) {
      this.RED?.log?.warn?.(
        `[${this.name}] bearer token loaded from legacy plain config field. ` +
        `Re-open this node in the editor and click Done to migrate to encrypted credentials.`
      );
    }
    const bearerToken = credentialToken || legacyToken;
    return cfgMgr.buildConfig(this.name, uiConfig, this.node.id, {
      functionality: {
        softwareType: this.name.toLowerCase(),
        role: 'auto ui generator',
      },
      grafanaConnector: {
        protocol: uiConfig.protocol || 'http',
        host: uiConfig.host || 'localhost',
        port: Number(uiConfig.port || 3000),
        bearerToken,
        folderUid: uiConfig.folderUid || '',
      },
      defaultBucket: uiConfig.defaultBucket || process.env.INFLUXDB_BUCKET || '',
    });
  }

  _attachInputHandler() {
    this.node.on('input', async (msg, send, done) => {
      try {
        await this._commands.dispatch(msg, this.source, {
          node: this.node,
          RED: this.RED,
          send,
          logger: this.source?.logger,
        });
        if (typeof done === 'function') done();
      } catch (error) {
        this.node.status({ fill: 'red', shape: 'ring', text: 'dashboardapi error' });
        this.node.error(error?.message || error, msg);
        if (typeof done === 'function') done(error);
      }
    });
  }

  _attachCloseHandler() {
    this.node.on('close', (done) => {
      if (this._flowsStartedListener && this.RED?.events?.off) {
        this.RED.events.off('flows:started', this._flowsStartedListener);
        this._flowsStartedListener = null;
      }
      if (typeof done === 'function') done();
    });
  }
}

module.exports = nodeClass;