#!/bin/bash

# Check if a file with ASINs is provided
if [ "$#" -ne 1 ]; then
    echo "Usage: $0 <asin_list_file>"
    exit 1
fi

ASIN_FILE=$1

# Check if the file exists
if [ ! -f "$ASIN_FILE" ]; then
    echo "File not found: $ASIN_FILE"
    exit 1
fi

# Create a directory to store the downloaded covers
mkdir -p covers

# Loop through each ASIN in the file
while IFS= read -r asin; do
    # Trim any whitespace
    asin=$(echo "$asin" | xargs)

    # Construct the high-resolution URL
    high_res_url="https://ec2.images-amazon.com/images/P/$asin.01.MAIN._SCRM_.jpg"
    echo "Attempting to download high-res cover for ASIN: $asin"

    # Download the high-resolution cover
    curl -o "covers/${asin}.jpg" "$high_res_url"

    # Check if the file exists and get its size
    if [ -f "covers/${asin}.jpg" ]; then
        file_size=$(wc -c < "covers/${asin}.jpg")  # Get file size in bytes

        # Check for invalid file sizes
        if [ "$file_size" -eq 43 ] || [ "$file_size" -eq 36 ]; then
            echo "High-res file is invalid (size: $file_size bytes), attempting lower-res."

            # Construct the lower-resolution URL
            low_res_url="https://images-na.ssl-images-amazon.com/images/P/$asin._SX1600_.jpg"
            curl -o "covers/${asin}.jpg" "$low_res_url"
        fi
    else
        echo "Failed to download high-res image for ASIN: $asin"
    fi
done < "$ASIN_FILE"

echo "Download complete. Covers saved in the 'covers' directory."