Update app.py

app.py

@@ -1,18 +1,26 @@
 import streamlit as st
 import primer3
-from Bio.Seq import Seq
+from Bio import SeqIO
+from io import StringIO
 
 # Streamlit app layout
 st.title('PCR Primer Design Tool')
-st.write('Enter your DNA sequence and target region to design PCR primers.')
+st.write('Upload a FASTA file with your DNA sequence to design PCR primers.')
 
-# User input for DNA sequence and target region
-user_sequence = st.text_area("Enter DNA sequence:", height=150).upper()  # Ensure sequence is uppercase
+# User input for DNA sequence via file upload
+fasta_file = st.file_uploader("Upload DNA sequence (FASTA format):", type=['fasta', 'fa'])
+
+# Input for target region
 target_start = st.number_input("Target start position:", min_value=0, value=0, step=1)
 target_length = st.number_input("Target length:", min_value=1, value=20, step=1)
 
 if st.button('Design Primers'):
-    if user_sequence and target_length > 0:
+    if fasta_file and target_length > 0:
+        # Read the sequence from the FASTA file
+        sequence_data = StringIO(fasta_file.getvalue().decode("utf-8"))
+        record = next(SeqIO.parse(sequence_data, "fasta"))
+        user_sequence = str(record.seq).upper()  # Ensure sequence is uppercase
+
         # Remove non-sequence characters (e.g., spaces, line breaks)
         clean_sequence = ''.join(user_sequence.split())
 
@@ -61,4 +69,4 @@ if st.button('Design Primers'):
             except Exception as e:
                 st.error(f"An error occurred while designing primers: {e}")
     else:
-        st.error('Please input a valid DNA sequence and specify a target region.')
+        st.error('Please upload a valid FASTA file and specify a target region.')