#!/bin/bash
set -euo pipefail

source ${HOME}/bin/script_framework.sh

check_util rankmirrors # from pacman-contrib

outfile=/etc/pacman.d/mirrorlist
oldlist=/etc/pacman.d/mirrorlist.bak

if [ $(id -u) -eq 0 ]; then
	step "Creating backup of current mirrorlist"
	cp /etc/pacman.d/mirrorlist /etc/pacman.d/mirrorlist.bak
else
	outfile=/tmp/mirrors.rank
	oldlist=/etc/pacman.d/mirrorlist
	warn "Not running as root, new mirrorlist will be written to ${outfile}"
fi

step "Collecting mirrors"
IFS=$'\n'
mirrors=(
	$(
		curl -sSfL "https://archlinux.org/mirrors/status/json/" |
			jq -r '.urls[] | select(.active) | select(.completion_pct == 1.0) | select( .delay < 3600) | select(.protocol == "https") | .url'
	)
)
unset IFS

step "Measuring mirror speed, searching 5 fastest mirrors of ${#mirrors[@]} mirrors"
for url in "${mirrors[@]}"; do
	echo "Server = ${url}\$repo/os/\$arch"
done |
	rankmirrors -n 5 - |
	tee "${outfile}"

step "Generating diff from old to new mirrorlist"
diff -wu "${oldlist}" "${outfile}"