#!/usr/bin/env bash

set -euo pipefail

BRANCH="update-inputs-$(date +%Y-%m-%d-%H-%M)"
HYDRA_URL="https://hydra.kyouma.net"
JOBSET_URL="${HYDRA_URL}/jobset/nixfiles/update-inputs"
ROOT="$(mktemp -d)"

gitin () {
  git -C "${ROOT}" "$@"
}

merge_theirs () {
  gitin merge -s ours "${BRANCH}" -m "Update from ${BRANCH}"
  gitin branch temp
  gitin reset --hard "${BRANCH}"
  gitin reset --soft temp
  gitin commit --amend --no-edit
  gitin branch -D temp
}

test_build () {
  local build_jobs
  build_jobs="$(curl --fail -s -L -H "Accept: application/json" "${JOBSET_URL}/latest-eval" | jq -r ".builds | .[]")"
  for build in ${build_jobs}; do 
    local build_status
    while true; do
      local build_finished
      build_finished="$(curl --fail -s -L -H "Accept: application/json" "${HYDRA_URL}/build/${build}" | jq -r ".finished")"
      [[ ${build_finished} == 1 ]] && break
      sleep 5
    done
    build_status="$(curl --fail -s -L -H "Accept: application/json" "${HYDRA_URL}/build/${build}" | jq -r ".buildstatus")"
    [[ $build_status != 0 ]] && echo "Build ${build} failed" && exit 1
    echo "Build ${build} was successful"
  done
}

wait_for_hydra () {
  local git_rev
  local hydra_rev
  local counter
  counter=0
  git_rev="$(gitin rev-parse update-inputs)"
  while [[ $counter -le 30 ]]; do
    hydra_rev="$(curl -s -L -H "Accept: application/json" "${JOBSET_URL}/latest-eval" 2> /dev/null | jq -r .flake | sed -E "s/.+&rev=(.*)/\1/g")"
    if [[ "${git_rev}" == "${hydra_rev}" ]]; then
      echo "Hydra got new commit"
      break
    fi
    sleep 30
    ((counter++))
  done
  if [[ $counter -ge 30 ]]; then 
    echo "Hydra no workey"
    exit 1
  fi
}

git clone git@git.bsd.gay:snaki/nixfiles.git "${ROOT}"
gitin fetch --all
gitin checkout origin/main

gitin checkout -b "${BRANCH}"

pushd "${ROOT}"
nix flake update --commit-lock-file
popd

if gitin diff --quiet origin/update-inputs "${BRANCH}"; then
  echo "No update needed"
  gitin checkout update-inputs
  gitin branch -D "${BRANCH}"
  exit 0
fi

gitin push --set-upstream origin "${BRANCH}"

gitin checkout update-inputs
merge_theirs 
gitin push origin update-inputs

echo "Waiting for hydra to get new commit"
wait_for_hydra

echo "Testing if all build jobs completed successfully"
test_build
echo "All build jobs were successful"

echo "Merging ${BRANCH} into main"
gitin checkout main
gitin merge --ff-only "${BRANCH}"
gitin push origin main
echo "Update successful"