import unittest
import subprocess

import interweave

# TestInterweave is a class that inherits from unittest.TestCase
class TestInterweave(unittest.TestCase):
    # setUp is a method that is run before each test
    def setUp(self):
        #add files paths for the fixture files
        self.file1 = "fixtures/file1.txt"
        self.file2 = "fixtures/file2.txt"
        self.file3 = "fixtures/file3.txt"
        self.file4 = "fixtures/file4.txt"
        self.output_file = "output.txt"
        self.expected_file = "expected.txt"
        #set the maximum difference to None, big file
        self.maxDiff = None

    # test_interweave is a method that tests the interweave function
    def test_interweave(self):
        #run the test
        self.run_test()
        #compare the output to the expected output
        self.compare_output()
    
    # run_test is a method that runs the command to interweave the files
    def run_test(self):
        #run the command to interweave the files
        subprocess.call(["python3", "interweave.py", self.file1, self.file2, self.file3, self.file4, self.output_file])
        
    # compare_output is a method that compares the output file to the expected output file    
    def compare_output(self):
        #open the output file
        output = open(self.output_file, "r")
        output_contents = output.read()
        #close the output file
        output.close()
        #open the expected output file
        expected = open(self.expected_file, "r")
        expected_contents = expected.read()
        #close the expected output file
        expected.close()
        #compare the output to the expected output
        self.assertEqual(output_contents, expected_contents)

# run the tests
if __name__ == '__main__':
    unittest.main()