import { getDb } from '../../db/index';
import { applyTransform, type TransformConfig } from './transforms';

export interface Datapoint {
  id: number;
  name: string;
  label: string;
  unit: string | null;
  value: string | null;
  status: string;
  source_type: string;
  source_id: number;
  topic_id: number | null;
  query_id: number | null;
  transform: string | null;
  enabled: number;
  updated_at: string;
}

export interface DatapointUpdate {
  label?: string;
  unit?: string;
  transform?: string | null;
  enabled?: number;
}

export function getAllDatapoints(): Datapoint[] {
  const db = getDb();
  return db
    .prepare('SELECT * FROM datapoints WHERE enabled = 1')
    .all() as Datapoint[];
}

export function getDatapointById(id: number): Datapoint | undefined {
  const db = getDb();
  return db
    .prepare('SELECT * FROM datapoints WHERE id = ?')
    .get(id) as Datapoint | undefined;
}

export function updateDatapointValue(id: number, rawValue: string): Datapoint | undefined {
  const db = getDb();
  const dp = db.prepare('SELECT * FROM datapoints WHERE id = ?').get(id) as Datapoint | undefined;
  if (!dp) return undefined;

  let config: TransformConfig | null = null;
  if (dp.transform) {
    try {
      config = JSON.parse(dp.transform) as TransformConfig;
    } catch {
      config = null;
    }
  }

  const transformed = applyTransform(rawValue, config);

  db.prepare(
    `UPDATE datapoints SET value = ?, status = 'ok', updated_at = datetime('now') WHERE id = ?`
  ).run(transformed, id);

  return db.prepare('SELECT * FROM datapoints WHERE id = ?').get(id) as Datapoint | undefined;
}

export function updateDatapoint(id: number, data: DatapointUpdate): Datapoint | undefined {
  const db = getDb();
  const fields: string[] = [];
  const values: unknown[] = [];

  if (data.label !== undefined) {
    fields.push('label = ?');
    values.push(data.label);
  }
  if (data.unit !== undefined) {
    fields.push('unit = ?');
    values.push(data.unit);
  }
  if (data.transform !== undefined) {
    fields.push('transform = ?');
    values.push(data.transform);
  }
  if (data.enabled !== undefined) {
    fields.push('enabled = ?');
    values.push(data.enabled);
  }

  if (fields.length === 0) return getDatapointById(id);

  values.push(id);
  db.prepare(`UPDATE datapoints SET ${fields.join(', ')} WHERE id = ?`).run(...values);
  return getDatapointById(id);
}

export function createDatapointFromMqtt(
  brokerId: number,
  topicId: number,
  topicPath: string
): Datapoint {
  const db = getDb();
  const result = db.prepare(
    `INSERT INTO datapoints (name, label, source_type, source_id, topic_id, enabled)
     VALUES (?, ?, 'mqtt', ?, ?, 1)`
  ).run(topicPath, topicPath, brokerId, topicId);
  const id = result.lastInsertRowid as number;
  return db.prepare('SELECT * FROM datapoints WHERE id = ?').get(id) as Datapoint;
}

export function createDatapointFromPg(
  sourceId: number,
  queryId: number,
  queryName: string
): Datapoint {
  const db = getDb();
  const result = db.prepare(
    `INSERT INTO datapoints (name, label, source_type, source_id, query_id, enabled)
     VALUES (?, ?, 'postgresql', ?, ?, 1)`
  ).run(queryName, queryName, sourceId, queryId);
  const id = result.lastInsertRowid as number;
  return db.prepare('SELECT * FROM datapoints WHERE id = ?').get(id) as Datapoint;
}

export function deleteDatapoint(id: number): boolean {
  const db = getDb();
  const result = db.prepare('DELETE FROM datapoints WHERE id = ?').run(id);
  return (result.changes as number) > 0;
}

export function getDatapointByTopicId(topicId: number): Datapoint | undefined {
  const db = getDb();
  return db
    .prepare('SELECT * FROM datapoints WHERE topic_id = ?')
    .get(topicId) as Datapoint | undefined;
}

export function getDatapointByQueryId(queryId: number): Datapoint | undefined {
  const db = getDb();
  return db
    .prepare('SELECT * FROM datapoints WHERE query_id = ?')
    .get(queryId) as Datapoint | undefined;
}