import { Stream } from 'stremio-addon-sdk';
import { flag } from 'country-emoji';
import winston from 'winston';
import bytes from 'bytes';
import { Context, UrlResult } from '../types';
import { Handler } from '../handler';
import { NotFoundError } from '../error';

export class StreamResolver {
  private readonly logger: winston.Logger;

  constructor(logger: winston.Logger) {
    this.logger = logger;
  }

  readonly resolve = async (ctx: Context, handlers: Handler[], type: string, id: string): Promise<Stream[]> => {
    if (handlers.length === 0) {
      return [{
        name: 'WebStreamr',
        title: '⚠️ No handlers found. Please re-configure the plugin.',
        ytId: 'E4WlUXrJgy4',
      }];
    }

    const streams: Stream[] = [];

    const urlResults: UrlResult[] = [];
    const handlerPromises = handlers.map(async (handler) => {
      if (!handler.contentTypes.includes(type)) {
        return;
      }

      try {
        const handlerUrlResults = await handler.handle(ctx, type, id);
        this.logger.info(`${handler.id} returned ${handlerUrlResults.length} urls`, ctx);

        urlResults.push(...(handlerUrlResults.filter(handlerUrlResult => handlerUrlResult !== undefined)));
      } catch (err) {
        if (err instanceof NotFoundError) {
          return;
        }

        streams.push({
          name: 'WebStreamr',
          title: `❌ Error with handler "${handler.id}". Please create an issue if this persists. Request-id: ${ctx.id}`,
          ytId: 'E4WlUXrJgy4',
        });

        this.logger.error(`${handler.id} error: ${err}`, ctx);
      }
    });
    await Promise.all(handlerPromises);

    urlResults.sort((a, b) => {
      const heightComparison = (b.meta.height ?? 0) - (a.meta.height ?? 0);
      if (heightComparison !== 0) {
        return heightComparison;
      }

      const bytesComparison = (b.meta.bytes ?? 0) - (a.meta.bytes ?? 0);
      if (bytesComparison !== 0) {
        return bytesComparison;
      }

      return a.label.localeCompare(b.label);
    });

    this.logger.info(`Return ${urlResults.length} streams`, ctx);

    streams.push(
      ...urlResults.map((urlResult) => {
        let name = 'WebStreamr';
        if (urlResult.meta.countryCode) {
          name += ` ${flag(urlResult.meta.countryCode)}`;
        }
        if (urlResult.meta.height) {
          name += ` ${urlResult.meta.height}p`;
        }
        if (urlResult.isExternal) {
          name += ` external`;
        }

        const titleSecondLineEntries: string[] = [];
        if (urlResult.meta.bytes) {
          titleSecondLineEntries.push(`💾 ${bytes.format(urlResult.meta.bytes, { unitSeparator: ' ' })}`);
        }
        titleSecondLineEntries.push(`⚙️ ${urlResult.label}`);

        const titleLines = [];
        if (urlResult.meta.title) {
          titleLines.push(urlResult.meta.title);
        }
        titleLines.push(titleSecondLineEntries.join(' '));
        if (urlResult.cloudflareChallenge) {
          titleLines.push('Request was blocked by Cloudflare.');
        }

        const title = titleLines.join('\n');

        return {
          [urlResult.isExternal ? 'externalUrl' : 'url']: urlResult.url.href,
          name,
          title,
          behaviorHints: {
            ...(urlResult.sourceId && { bingeGroup: `webstreamr-${urlResult.sourceId}` }),
            ...(urlResult.requestHeaders !== undefined && {
              notWebReady: true,
              proxyHeaders: { request: urlResult.requestHeaders },
            }),
            ...(urlResult.meta.bytes && { videoSize: urlResult.meta.bytes }),
          },
        };
      }),
    );

    return streams;
  };
}