import { getConfig } from '@openmrs/esm-framework';
export interface PrintLogoData {
  image: string;
  isSvg: boolean;
}

export const GetPrintLogo = async (): Promise<PrintLogoData | null> => {
  const config = await getConfig('@openmrs/esm-stock-management-app');
  const printLogoUrl = config?.logo?.src;
  return new Promise((resolve, reject) => {
    if (!printLogoUrl) {
      resolve(null);
      return;
    }

    const hdnTxtPrintLogo = document.getElementById('hdnTxtPrintLogo') as HTMLTextAreaElement;
    if (hdnTxtPrintLogo && hdnTxtPrintLogo.value?.length > 0) {
      const isSvg = hdnTxtPrintLogo.getAttribute('isSvg');
      resolve({
        image: (hdnTxtPrintLogo as HTMLTextAreaElement).value,
        isSvg: isSvg === '1',
      });
      return;
    }

    if (printLogoUrl.toLowerCase().endsWith('.svg')) {
      fetch(printLogoUrl, {
        headers: {
          'Disable-WWW-Authenticate': 'true',
        },
      })
        .then((response) => {
          if (!response.ok) {
            throw new Error('Print logo fetch network response was not OK');
          }
          return response.text();
        })
        .then((svg) => {
          if (hdnTxtPrintLogo) {
            hdnTxtPrintLogo.value = svg;
            hdnTxtPrintLogo.setAttribute('isSvg', '1');
          }
          resolve({ image: svg, isSvg: true });
        })
        .catch((error) => {
          console.error('Error fetching print logo: ', error);
          reject('Error fetching print logo');
        });
    } else {
      const img = new Image();
      const onImageLoaded = () => {
        try {
          const canvas = document.createElement('canvas');
          canvas.width = img.width;
          canvas.height = img.height;
          const ctx = canvas.getContext('2d');
          if (ctx) {
            ctx.drawImage(img, 0, 0);
            const dataURL = canvas.toDataURL('image/png');
            if (hdnTxtPrintLogo) {
              hdnTxtPrintLogo.value = dataURL;
              hdnTxtPrintLogo.setAttribute('isSvg', '0');
            }
            resolve({ image: dataURL, isSvg: false });
          } else {
            reject('Failed to allocate canvas context for print logo');
          }
        } catch (e) {
          reject(e);
        }
      };
      const onImageLoadError = (ev: ErrorEvent) => {
        reject(ev);
      };
      img.addEventListener('load', onImageLoaded);
      img.addEventListener('error', onImageLoadError);
      img.src = printLogoUrl;
    }
  });
};