import {
    checkIfFileExists,
    deleteOriginalImageFromBucket,
    downloadFileFromBucket,
    getBucket,
    uploadFileToBucket,
} from './buckets';
import { deleteFile, getFilename, getLocalFilePath } from './local';
import { resizeImageToFitDimensions, shouldResizeImage } from './resize';
import { compressImage, shouldCompressImage } from './compress';
import { RESULT_RETURN_LABELS } from './constants';

const getReturnLabel = ({
    shouldCompress,
    shouldResize,
}: {
    shouldCompress: boolean;
    shouldResize: boolean;
}): RESULT_RETURN_LABELS => {
    switch (true) {
        case !shouldCompress && !shouldResize:
            return RESULT_RETURN_LABELS.NOTHING_TO_DO;
        case shouldCompress && !shouldResize:
            return RESULT_RETURN_LABELS.ONLY_COMPRESS;
        case shouldResize && !shouldCompress:
            return RESULT_RETURN_LABELS.ONLY_RESIZE;
        case shouldResize && shouldCompress:
        default:
            return RESULT_RETURN_LABELS.BOTH;
    }
};

// This method implements the call from Cloud Storage new object trigger https://cloud.google.com/functions/docs/calling/storage#object_finalize
const compressAndResizeBucketImage = async (
    { bucket: bucketName, name: filePath }: { bucket: string; name: string },
    // eslint-disable-next-line @typescript-eslint/no-explicit-any
    context: any,
    callback: (e: Error | null, label?: RESULT_RETURN_LABELS) => void,
): Promise<void> => {
    try {
        /*
         * PREPARE
         */
        const shouldResize = shouldResizeImage(filePath);
        const shouldCompress = shouldCompressImage(filePath);

        if (!shouldResize && !shouldCompress) {
            return callback(null, getReturnLabel({ shouldResize, shouldCompress }));
        }

        console.log(`[TRIGGERED] Compress and Resizing ${filePath}`);

        const bucket = getBucket(bucketName);
        const filename = getFilename(filePath);
        const localfilePath = getLocalFilePath(filename);

        /*
         * FETCH
         */

        await checkIfFileExists({ bucket, filePath });
        const file = await downloadFileFromBucket({ bucket, localfilePath, filePath });

        /*
         * RESIZE
         */

        if (shouldResize) {
            await resizeImageToFitDimensions(localfilePath);
        }

        /*
         * COMPRESS
         */

        if (shouldCompress) {
            await compressImage(localfilePath);
        }

        /*
         * UPLOAD
         */
        // Upload resized image to base_directory
        await uploadFileToBucket({ bucket, localfilePath, filePath });

        /*
         * CLEAN
         */
        // Remove image from base_directory/toBeResized
        await deleteOriginalImageFromBucket({ bucket, filePath: file });
        await deleteFile(localfilePath);

        // callback
        const returnLabel = getReturnLabel({ shouldResize, shouldCompress });
        return callback(null, returnLabel);
    } catch (e) {
        // TODO(@kevin ?): handle error
        console.error(e);
        return callback(e as Error);
    }
};

export { compressAndResizeBucketImage };