#!/bin/bash
# Clones all student repos from GitHub Classroom using the GitHub CLI with GitHub Classroom extension
# Accepts an assignment ID as an argument
# If no argument is provided, it will show all assignments and prompt for one
# If there are more than 30 repos, it will prompt to continue and clone the next page until all repos are cloned

# Function to round up
ceil() {
	num=$1
	printf "%.0f\n" $(echo "$num + 0.999" | bc)
}

# Function to divide and round up
ceil_divide() {
	local num1=$1
	local num2=$2
	local result=$(echo "scale=10; $num1 / $num2" | bc)
	local rounded_up=$(echo "$result" | awk '{print ($0 == int($0)) ? $0 : int($0)+1}')
	echo $rounded_up
}

# Function to strip colors
strip_colors() {
	sed -E 's/\x1B\[[0-9;]*[mK]//g'
}

# Check if GitHub CLI is installed
if ! command -v gh &> /dev/null
then
	echo "GitHub CLI could not be found. Please install it from https://cli.github.com/"
	exit
fi

# Check if GitHub Classroom extension is installed
if ! gh extension list | grep -q "gh-classroom"
then
	echo "GitHub Classroom extension could not be found. Please install it by running 'gh extension install classroom'"
	exit
fi

# Get the assignment ID
if [ -z "$1" ]
then
	gh classroom assignments
	echo ""
	echo -n "Enter the assignment ID: "
	read assignment_id
	echo ""
else
	assignment_id=$1
fi

echo "🔄 Cloning student repos..."
echo ""

# Get count of repos
repos=$(gh classroom assignment -a $assignment_id | /usr/bin/grep --color=never "Accepted" | cut -d " " -f 2 | strip_colors)
echo "📚 Total repos: $repos"

# We can only clone 30 repos at a time
# Calculate the number of pages and round up
per_page=30
echo "📃 Per page: $per_page"
pages=$(ceil_divide $repos $per_page)
echo "📄 Total pages: $pages"
echo ""

# Start at page 1
page=1

# Clone the repos until all pages are cloned
while [ $page -le $pages ]
do
	echo "🔍 Cloning page $page..."
	gh classroom clone student-repos -a $assignment_id --page $page
	page=$((page + 1))
	echo ""
done

echo ""
echo "🎉 All repos have been cloned"
echo ""