import type { IBalenaDeviceState, IBalenaStateStatus } from './types.ts';

export interface ISupervisorClientOptions {
  address?: string;
  apiKey?: string;
}

export class SupervisorClient {
  public readonly address?: string;
  private readonly apiKey?: string;

  constructor(optionsArg: ISupervisorClientOptions = {}) {
    this.address = optionsArg.address || Deno.env.get('BALENA_SUPERVISOR_ADDRESS') || undefined;
    this.apiKey = optionsArg.apiKey || Deno.env.get('BALENA_SUPERVISOR_API_KEY') || undefined;
  }

  public isConfigured() {
    return Boolean(this.address);
  }

  public async isAvailable() {
    if (!this.address) {
      return false;
    }
    try {
      const response = await fetch(this.buildUrl('/ping', false));
      const text = await response.text();
      return response.ok && text.trim() === 'OK';
    } catch {
      return false;
    }
  }

  public async getDeviceState(): Promise<IBalenaDeviceState> {
    return await this.requestJson<IBalenaDeviceState>('/v1/device');
  }

  public async getStateStatus(): Promise<IBalenaStateStatus> {
    return await this.requestJson<IBalenaStateStatus>('/v2/state/status');
  }

  public async getSupervisorVersion(): Promise<string | undefined> {
    const response = await this.requestJson<{ version?: string }>('/v2/version');
    return response.version;
  }

  public async triggerUpdate(optionsArg: { force?: boolean; cancel?: boolean } = {}) {
    await this.requestEmpty('/v1/update', {
      method: 'POST',
      body: JSON.stringify({
        force: Boolean(optionsArg.force),
        cancel: Boolean(optionsArg.cancel),
      }),
      headers: {
        'content-type': 'application/json',
      },
    });
  }

  public async reboot(optionsArg: { force?: boolean } = {}) {
    await this.requestEmpty('/v1/reboot', {
      method: 'POST',
      body: JSON.stringify({
        force: Boolean(optionsArg.force),
      }),
      headers: {
        'content-type': 'application/json',
      },
    });
  }

  private async requestJson<TResponse>(
    pathArg: string,
    initArg: RequestInit = {},
  ): Promise<TResponse> {
    const response = await fetch(this.buildUrl(pathArg, true), initArg);
    if (!response.ok) {
      throw new Error(`Supervisor request failed: ${pathArg} -> HTTP ${response.status}`);
    }
    return await response.json() as TResponse;
  }

  private async requestEmpty(pathArg: string, initArg: RequestInit = {}) {
    const response = await fetch(this.buildUrl(pathArg, true), initArg);
    if (!response.ok) {
      throw new Error(`Supervisor request failed: ${pathArg} -> HTTP ${response.status}`);
    }
  }

  private buildUrl(pathArg: string, includeApiKeyArg: boolean) {
    if (!this.address) {
      throw new Error('Balena Supervisor address is not configured');
    }
    const url = new URL(pathArg, this.address.endsWith('/') ? this.address : `${this.address}/`);
    if (includeApiKeyArg) {
      if (!this.apiKey) {
        throw new Error('Balena Supervisor API key is not configured');
      }
      url.searchParams.set('apikey', this.apiKey);
    }
    return url;
  }
}