# function set assumes AWS credentials are already set locally

import boto3
import botocore

session = boto3.Session()
S3 = session.resource('s3')

# case insensitive find objects function
# all kw must match for a target match
# any ignore kw is an ignore match
def findObjects(bucket, TARGET_KW, IGNORE_KW = []):
    my_bucket = S3.Bucket(bucket)
    filelst = []
    
    for obj in my_bucket.objects.all():
        ignoreflag = 0
        matchcount = 0
        
        # adjust case for proper matching
        filename = obj.key.lower()
        TARGET_KW = [x.lower() for x in TARGET_KW]
        IGNORE_KW = [x.lower() for x in IGNORE_KW]

        # filename must have all target kw's
        for targetkw in TARGET_KW:
            if filename.find(targetkw.lower()) != -1:
                matchcount += 1

        # filename will ignore for any ignore kw match(es)
        if matchcount == len(TARGET_KW) and len(IGNORE_KW) > 0:
            for ignorekw in IGNORE_KW:
                if filename.find(ignorekw.lower()) != -1:
                    ignoreflag = 1

        # process only if no ignore kw triggered and ALL target kw matched
        if ignoreflag == 0 and matchcount == len(TARGET_KW):
            filelst.append(obj.key)
                
    return filelst


# aws download function, file name is kept the same unless specified
def downloadObjects(bucket, file, destfilename = None, path = None):
    if destfilename is None:
        destfilename = file.split('/')[-1]
        
    if path is not None:
        destfilename += path
        
    try:
        S3.Bucket(bucket).download_file(file, destfilename)
        
    except botocore.exceptions.ClientError as e:
        if e.response['Error']['Code'] == "404":
            print("The object does not exist.")
        else:
            raise