import frappe
from .utils import get_course, add_nav

def get_context(context):
    context.no_cache = 1
    context.course = get_course()
    if frappe.session.user == "Guest":
        frappe.local.flags.redirect_location = "/login?redirect-to=" + frappe.request.path
        raise frappe.Redirect()

    if not context.course:
        context.template = "www/404.html"
        return

    context.cohorts = get_cohorts(context.course)
    if len(context.cohorts) == 1:
        frappe.local.flags.redirect_location = context.cohorts[0].get_url()
        raise frappe.Redirect

    add_nav(context, "All Courses", "/courses")
    add_nav(context, context.course.title, "/courses/" + context.course.name)

def get_cohorts(course):
    if "System Manager" in frappe.get_roles():
        return course.get_cohorts()

    staff_roles = frappe.get_all("Cohort Staff", filters={"course": course.name}, fields=["cohort"])
    mentor_roles = frappe.get_all("Cohort Mentor", filters={"course": course.name}, fields=["cohort"])
    roles = staff_roles + mentor_roles
    names = {role.cohort for role in roles}
    return [frappe.get_doc("Cohort", name) for name in names]