import re

def match_query_pattern(query, patterns):

"""

Matches a query string against a list of patterns, with fallback logic.

Args:

query (str): The query string to match.

patterns (list of tuples): A list of (pattern, value) tuples.

Pattern is a regex string.

Returns:

str: The matched value if a pattern matches, otherwise None.

"""

for pattern, value in patterns:

match = re.search(pattern, query) # Search for the pattern in the query

if match:

return value # Return the value if a match is found

return None # Return None if no pattern matches

if __name__ == '__main__':

# Example Usage

patterns = [

(r"color=(.*)", "color"), # Matches "color=..." and returns "color"

(r"size=(.*)", "size"), # Matches "size=..." and returns "size"

(r"price=(\d+\.?\d*)", "price"), # Matches "price=..." and returns "price"

(r"category=(.*)", "category"), # Matches "category=..." and returns "category"

(r"discount=(.*)", "discount") # Matches "discount=..." and returns "discount"

]

query1 = "color=red&size=large"

query2 = "price=25.99"

query3 = "category=electronics&discount=10%"

query4 = "someotherparam=value"

query5 = "size=small&color=blue"

query6 = "invalid_param=value"

print(f"Query: {query1}, Match: {match_query_pattern(query1, patterns)}")

print(f"Query: {query2}, Match: {match_query_pattern(query2, patterns)}")

print(f"Query: {query3}, Match: {match_query_pattern(query3, patterns)}")

print(f"Query: {query4}, Match: {match_query_pattern(query4, patterns)}")

print(f"Query: {query5}, Match: {match_query_pattern(query5, patterns)}")

print(f"Query: {query6}, Match: {match_query_pattern(query6, patterns)}")