# File: courseSelector.py
# Purpose: Different classes to select courses in order to maximize
#          value without going over the limit of available effort.
#
# Author: TODO
#
# Collaboration statement: TODO

from course import Course

#############################################################

class CourseSelector:
    def __init__(self, courses = []):
        self.courses = courses[:] # copy the courses

    def addCourse(self, course):
        self.courses.append(course)

    def chooseCourses(self, maxEffort):
        raise NotImplementedError # will implement in a subclass
    
#############################################################

class GreedyCourseSelector(CourseSelector):
    def __init__(self, courses = []):
        # Don't do anything special, just call the parent constructor
        # to initialize the courses
        CourseSelector.__init__(self, courses)

    def greedyChoice(self, course):
        raise NotImplementedError # will implement in subclasses

    def chooseCourses(self, maxEffort):
        """
        Choose courses greedily, using a pre-determined greedy
        evaluation function, without going over maxEffort.

        returns: value, effort, and list of courses
        """
        # Sort the courses based on the greedy evaluation function
        # (this must be defined in subclasses)

        # Choose courses as long as the total effort isn't more
        # than maxEffort

        # Return the value, effort, and the chosen courses
        return 0, 0, [] # TODO: replace with your code
    
#############################################################

class ValueGreedyCourseSelector(GreedyCourseSelector):
    """
    A greedy course selector that favors courses with high value,
    regardless of effort.
    """
    
    def __init__(self, courses = []):
        # Don't do anything special, just call the parent constructor
        # to initialize the courses
        GreedyCourseSelector.__init__(self, courses)

    def greedyChoice(self, course):
        # Favor courses with high value, regardless of effort
        return 0 # TODO: replace with your code

class EffortGreedyCourseSelector(GreedyCourseSelector):
    """
    A greedy course selector that favors courses with low effort,
    regardless of value.
    """
    
    def __init__(self, courses = []):
        # Don't do anything special, just call the parent constructor
        # to initialize the courses
        GreedyCourseSelector.__init__(self, courses)

    def greedyChoice(self, course):
        # Favor courses with low effort, regardless of value
        return 0 # TODO: replace with your code

class ValuePerEffortGreedyCourseSelector(GreedyCourseSelector):
    """
    A greedy course selector that favors courses with high
    value-to-effort ratio.
    """
    
    def __init__(self, courses = []):
        # Don't do anything special, just call the parent constructor
        # to initialize the courses
        GreedyCourseSelector.__init__(self, courses)

    def greedyChoice(self, course):
        # Favor courses with high value-to-effort ratio
        return 0 # TODO: replace with your code
    
#############################################################

def testSolutions():
    courses = [Course("A", 6, 10, 4),
               Course("B", 6, 5, 10),
               Course("C", 6, 2, 4),
               Course("D", 6, 6, 8),
               Course("E", 6, 3, 3),
               Course("F", 6, 8, 2),
               Course("G", 6, 4, 7)]

    valueGreedyCourseSelector = ValueGreedyCourseSelector(courses)
    effortGreedyCourseSelector = EffortGreedyCourseSelector(courses)
    valuePerEffortGreedyCourseSelector = ValuePerEffortGreedyCourseSelector(courses)

    maxEffort = 12
    
    print("Maximum effort:", maxEffort)

    print("\nValue greedy result:")
    res = valueGreedyCourseSelector.chooseCourses(maxEffort)
    print("  value:", res[0])
    print("  effort:", res[1])
    for course in res[2]:
        print("  " + str(course))

    print("\nEffort greedy result:")
    res = effortGreedyCourseSelector.chooseCourses(maxEffort)
    print("  value:", res[0])
    print("  effort:", res[1])
    for course in res[2]:
        print("  " + str(course))        

    print("\nValue-to-effort ratio greedy result:")
    res = valuePerEffortGreedyCourseSelector.chooseCourses(maxEffort)
    print("  value:", res[0])
    print("  effort:", res[1])
    for course in res[2]:
        print("  " + str(course))

if __name__ == "__main__":
    testSolutions()