class PetrolAction extends ActionBase {
  constructor($UD, context) {
    super($UD, context);
    this.config = {
      url: '',
      stationUuid: '',
      fuelType: '',
      refreshRate: '1',
    };
    this.previousPrice = null;
    this.lastRised = null;
    this.prevLastRised = null;

    this.$UD.onDidReceiveSettings(jsn => {
      if (jsn.context !== this.context) return;
      const s = jsn.settings || {};
      this.config = Object.assign(this.config, s);
      if (s.previousPrice != null) this.previousPrice = s.previousPrice;
      if (s.lastRised > 0) this.lastRised = s.lastRised;
      if (s.prevLastRised > 0) this.prevLastRised = s.prevLastRised;
    });
  }

  setActive() {}

  setParams(jsn) {
    this.config = Object.assign(this.config, (jsn && jsn.param) || {});
    this.$UD.getSettings(this.context);
    this.startTimer(() => this.fetchPrice(), this.config.refreshRate);
  }

  onRun() {
    this.fetchPrice();
  }

  fetchPrice() {
    this.debounce(async () => {
      if (!this.config.url || !this.config.stationUuid || !this.config.fuelType) {
        this.renderButton('?');
        return;
      }
      try {
        const response = await fetch(this.config.url);
        const text = await response.text();
        const raw = this.parsePrometheus(text);
        if (raw) {
          const current = parseFloat(raw);
          if (this.previousPrice !== null) {
            const delta = current - this.previousPrice;
            if (delta > 0) {
              this.prevLastRised = this.lastRised;
              this.lastRised = current;
            }
          }
          this.previousPrice = current;

          this.renderButton(`${parseFloat(raw).toFixed(3)}€`);
          this.$UD.setSettings({
            ...this.config,
            previousPrice: this.previousPrice,
            lastRised: this.lastRised,
            prevLastRised: this.prevLastRised,
          }, this.context);
        } else {
          this.renderButton('N/A');
        }
      } catch (e) {
        this.renderButton('ERR');
      }
    });
  }

  parsePrometheus(text) {
    for (const line of text.split('\n')) {
      const trimmed = line.trim();
      if (!trimmed || trimmed.startsWith('#')) continue;
      if (trimmed.startsWith('petrol_price_euro') && trimmed.includes(this.config.stationUuid) && trimmed.includes(this.config.fuelType)) {
        const closingBrace = trimmed.indexOf('}');
        if (closingBrace !== -1) return trimmed.slice(closingBrace + 1).trim();
      }
    }
    return null;
  }

  renderButton(priceText) {
    const { canvas, ctx } = this.createCanvas();

    let risedColor = '#888888';
    if (this.lastRised > 0 && this.prevLastRised > 0) {
      risedColor = this.lastRised < this.prevLastRised ? '#6bff6b' : '#ff6b6b';
    }

    if (this.lastRised !== null) {
      ctx.fillStyle = '#7ec8e3';
      ctx.font = 'bold 22px "Source Han Sans SC"';
      ctx.fillText(this.config.fuelType, 98, 25);

      const fSize = priceText.length > 6 ? 36 : 42;
      ctx.fillStyle = '#f0c040';
      ctx.font = `bold ${fSize}px "Source Han Sans SC"`;
      ctx.fillText(priceText, 98, 82);

      ctx.fillStyle = '#888888';
      ctx.font = '20px "Source Han Sans SC"';
      ctx.fillText(this.$UD.t('Last Rised'), 98, 130);
      ctx.fillStyle = risedColor;
      ctx.font = 'bold 28px "Source Han Sans SC"';
      ctx.fillText(`${this.lastRised.toFixed(3)}€`, 98, 162);
    } else {
      ctx.fillStyle = '#7ec8e3';
      ctx.font = 'bold 28px "Source Han Sans SC"';
      ctx.fillText(this.config.fuelType, 98, 42);

      const fSize = priceText.length > 6 ? 38 : 46;
      ctx.fillStyle = '#f0c040';
      ctx.font = `bold ${fSize}px "Source Han Sans SC"`;
      ctx.fillText(priceText, 98, 105);
    }

    this.setIcon(canvas);
  }
}