#!/usr/bin/env bash
set -eo pipefail

readonly ROOT_DIR="$(cd "$(dirname "$(dirname "${BASH_SOURCE[0]}")")" && pwd)"

main() {
  pushd "$ROOT_DIR" >/dev/null || return 1
  rm -rf docs-main tmp/docs-source tmp/docs-build # tmp/docs-build
  cp -r docs docs-main

  echo "====> Generating docs image"
  make docs-build-image

  echo "====> Fetching latest docs"
  git clone -q https://github.com/dokku/docs.git tmp/docs-build

  echo "====> Processing version: latest"
  rm -rf tmp/docs-build/docs
  git clone -q https://github.com/dokku/dokku.git tmp/docs-source

  rm -rf docs/assets
  mkdir -p docs/assets
  cp -r docs-main/assets/extra.css docs/assets/extra.css
  cp -r docs-main/assets/favicons docs/assets/favicons
  cp -r docs-main/assets/dokku-logo.svg docs/assets/dokku-logo.svg

  rm -rf tmp/docs-build/assets
  cp -r docs-main/assets tmp/docs-build/assets
  cp docs-main/_build/app-nginx.conf.sigil tmp/docs-build/app-nginx.conf.sigil
  mkdir -p tmp/docs-build/nginx.conf.d
  touch tmp/docs-build/.static
  echo "[]" >tmp/docs-build/versions.json

  sed -i.bak "s/outdated/outdated_hidden/g" docs/_overrides/main.html && rm docs/_overrides/main.html.bak
  echo "----> Generating docs"
  make docs-build
  if [[ -n "$GITHUB_ACTION" ]]; then
    sudo chown -R "$(whoami)" site
  fi

  rm -rf site/_build
  mv site tmp/docs-build/docs
  mv docs/home.html tmp/docs-build/index.html
  sed -i.bak "s/{{NAME}}~{{REF}}/docs/g" tmp/docs-build/index.html && rm tmp/docs-build/index.html.bak
  sed -i.bak "s/{{NAME}}/docs/g" tmp/docs-build/index.html && rm tmp/docs-build/index.html.bak
  sed -i.bak 's/="\/docs\/"/="\/"/g' tmp/docs-build/index.html && rm tmp/docs-build/index.html.bak

  jq -C -r '.["max-versions"][]' docs-main/assets/versions.json | while read -r current_version; do
    major="$(echo "$current_version" | cut -d'.' -f1)"
    minor="$(echo "$current_version" | cut -d'.' -f2)"
    patch="$(echo "$current_version" | cut -d'.' -f3)"
    while true; do
      if [[ "$patch" -lt 0 ]]; then
        break
      fi
      version="${major}.${minor}.${patch}"
      echo "====> Processing version: ${major}.${minor}.${patch}"

      if [[ "$major" -lt 1 ]]; then
        if [[ "$current_version" != "$version" ]]; then
          echo "      Writing rewrite rule"
          echo "rewrite ^/docs~v$version/(.*)$ /docs~v$current_version/\$1 redirect;" >"tmp/docs-build/nginx.conf.d/$version.conf"
          echo "      Removing old docs"
          rm -rf "tmp/docs-build/docs~v${version}"
          patch=$((patch - 1))
          continue
        fi
      fi

      jq --arg title "v$version" --arg version "docs~v$version" '. += [{"title": $title, "version": $version, "aliases": []}]' tmp/docs-build/versions.json >tmp/docs-build/versions.json.bak
      mv tmp/docs-build/versions.json.bak tmp/docs-build/versions.json
      if [[ -d "tmp/docs-build/docs~v${version}" ]]; then
        echo " !    Docs exist, skipping regeneration"
        rm -rf "tmp/docs-build/docs~v${version}/assets/favicons"
        cp -r docs-main/assets/favicons "tmp/docs-build/docs~v${version}/assets/favicons"
        cp -r docs-main/assets/dokku-logo.svg "tmp/docs-build/docs~v${version}/assets/dokku-logo.svg"
        cp -r docs-main/assets/extra.css "tmp/docs-build/docs~v${version}/assets/extra.css"
        patch=$((patch - 1))
        continue
      fi

      git -C tmp/docs-source checkout -q -- .
      git -C tmp/docs-source checkout -q "tags/v${version}" -b "v${version}-branch"
      rm -rf docs
      mv tmp/docs-source/docs docs

      rm -rf docs/assets
      mkdir -p docs/assets
      cp -r docs-main/assets/favicons docs/assets/favicons
      cp -r docs-main/assets/dokku-logo.svg docs/assets/dokku-logo.svg
      cp -r docs-main/assets/extra.css docs/assets/extra.css

      cp -r docs-main/_build docs/_build
      cp -r docs-main/_overrides docs/_overrides
      git checkout -q -- mkdocs.yml
      sed -i.bak "s/site_dir: site/site_dir: docs~v$version/g" mkdocs.yml && rm mkdocs.yml.bak
      if [[ ! -f docs/template.html ]]; then
        if [[ "$patch" -eq 0 ]]; then
          break
        fi

        continue
      fi

      echo "----> Generating docs"
      if ! make docs-build; then
        continue
      fi

      if [[ -d "docs~v${version}" ]]; then
        if [[ -n "$GITHUB_ACTION" ]]; then
          sudo chown -R "$(whoami)" "docs~v${version}"
        fi

        rm -rf "docs~v${version}/_build"
        mv "docs~v${version}" "tmp/docs-build/docs~v${version}"
      fi

      if [[ "$patch" -eq 0 ]]; then
        break
      fi
      patch=$((patch - 1))
    done
  done

  echo "====> Rebuild versions"
  if [[ -f "tmp/docs-build/versions.json" ]]; then
    python3 contrib/sort-mkdocs-versions
  else
    echo "      No version file exists"
  fi

  echo "====> Cleanup main repo"
  rm -rf docs
  mv docs-main docs
  git checkout -- mkdocs.yml docs

  echo "====> Checking for file changes"
  changes=$(git -C tmp/docs-build ls-files -dmo)
  if [[ -z "$changes" ]]; then
    echo " !    No doc changes found"
    exit 0
  fi

  if [[ "$changes" == "docs/sitemap.xml.gz" ]]; then
    echo " !    No doc changes found"
    git -C tmp/docs-build checkout -- docs/sitemap.xml.gz
    exit 0
  fi

  echo "====> Changes found"
  echo "$changes"

  echo "====> Committing changes"
  git -C tmp/docs-build add .
  git -C tmp/docs-build commit -m "chore: regenerate docs"

  echo "====> Pushing changes"
  if [[ -n "$BOT_GITHUB_USERNAME" ]] && [[ -n "$BOT_GITHUB_API_TOKEN" ]]; then
    git -C tmp/docs-build remote set-url origin "https://$BOT_GITHUB_USERNAME:$BOT_GITHUB_API_TOKEN@github.com/dokku/docs.git"
  fi

  git -C tmp/docs-build push origin master

}

main "$@"