import random

data = {
'students' : ['allie','AndreaAngquist', 'andrew.c.chao','arielhaney','deepaks', 'donghyuk-jung', 'Elliot', 'emilybarabas', 'gahernandez', 'gshapiro','icheung','jenmwang', 'Matt Acalin','natarajan','sam', 'vimalkini', 'brendanmcurran','awootton44','karthikv','gaurav.shetti', 'rami'],

'project_1' : [['brendanmcurran', 'arielhaney', 'awootton44'], ['AndreaAngquist','gshapiro','andrew.c.chao'],['achung','arielhaney','donghyuk-jung'],['gahernandez','icheung','Matt Acalin','allie'],['gaurav.shetti','vimalkini'],
['sam','Elliot','jenmwang'],
['natarajan','karthikv'],
['rami','deepaks','saghar'],],

'project_2' : [['sam','allie','andrew.c.chao'],['gahernandez','arielhaney','jenmwang'],['vimalkini','icheung'],
['brendanmcurran','karthikv','Matt Acalin'], ['natarajan','gaurav.shetti'],['AndrewAngquist','Elliot','awootton44','rami'],['deepaks','emilybarabas','gshapiro','donghyuk-jung']],

'project_3' : [['rami','icheung','awootton44'],['brendanmcurran','arielhaney','natarajan'],['Elliot','jenmwang','andrew.c.chao'],['deepaks','allie','gaurav.shetti'],['sam','gahernandez','gshapiro'],
['Matt Acalin','AndreaAngquist','awootton44'],
['vimalkini','donghyuk-jung','karthikv']]
}

students_list = data['students']

group_size = 3

def main():
    '''Outputs a list of entirely novel, semi-random groups based on the student data, and/or returns an unprocessable remainder'''
    print "New groups: "
    while len(students_list) > group_size:
        root_student = students_list.pop(0)
        make_group([root_student])
    print "Remainder: " + serial(students_list)


def make_group(current_group,counter=0):
    if len(current_group) == group_size:
        print serial(current_group)
    elif counter > 10 or len(students_list) < 1:
        print 'Stalled on group [' + serial(current_group) + '] with remainder [' + serial(students_list) + ']'
    else:
        index = random.randint(0,len(students_list)-1)
        new_student = students_list[index]
        if new_to_group(new_student,current_group):
            current_group.append(new_student)
            students_list.pop(index)
            make_group(current_group,counter)
        else:
            make_group(current_group,counter+1)

def new_to_group(new_student,group):
    '''Checks if a given student has worked with any of the members of a given group before'''
    is_new = True
    for student in group:
        if have_worked_together(student,new_student):
            is_new = False
    return is_new

def have_worked_together(student1, student2):
    '''Takes two students, returns True if they've worked together in the past'''
    fact = False
    # if any function call returns True, fact will become True
    fact = fact or work_together_helper(data['project_1'],student1,student2)
    fact = fact or work_together_helper(data['project_2'],student1,student2)
    fact = fact or work_together_helper(data['project_3'],student1,student2)
    return fact

def work_together_helper(project, student1, student2):
    for team in project:
        if student1 in team:
            if student2 in team:
                return True
            break
    return False

def has_worked_with(student):
    '''Returns a list of people that a given student has worked with in the past, checking for repeats'''
    # Not called by the main function in any way, but useful for checking results
    projects=[data['project_1'],data['project_2'],data['project_3']]
    worked_with_dico = {}
    worked_with_list = []
    for project in projects:
        for team in project:
            if student in team:
                for person in team:
                    if person != student and not person in worked_with_dico:
                        worked_with_list.append(person)
                        worked_with_dico[person] = 1
    return worked_with_list

def serial(list):
    '''Takes either a string or a list of strings; if it's a string, returns the string, if it's a list, turns it into a comma-delineated string'''
    if type(list) == type(str()):
        return list
    elif list:
        s = ''
        for item in list:
            s = s + item + ', '
        return s
    else:
        return ""