name: release

on:
  push:
    tags:
      - "v*"
  workflow_dispatch:

permissions:
  contents: write
  pull-requests: read

jobs:
  release:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
        with:
          fetch-depth: 0
          fetch-tags: true

      - name: Generate changelog
        id: changelog
        env:
          GH_TOKEN: ${{ github.token }}
        run: |
          set -euo pipefail
          TAG="${GITHUB_REF_NAME}"
          REPO="${GITHUB_REPOSITORY}"

          # previous tag (parent of this tag)
          PREV_TAG="$(git describe --tags --abbrev=0 HEAD^ 2>/dev/null || echo "")"

          if [ -z "$PREV_TAG" ]; then
            RANGE="HEAD"
            echo "No previous tag, using all history"
          else
            RANGE="${PREV_TAG}..HEAD"
            echo "Range: $RANGE"
          fi

          FEATS=""
          FIXES=""

          parse_conventional() {
            local text="$1"
            ENTRY_TYPE=""
            ENTRY_TITLE=""
            local pattern='^(feat|fix)(\([^)]*\))?!?:[[:space:]](.+)$'
            if [[ "$text" =~ $pattern ]]; then
              ENTRY_TYPE="${BASH_REMATCH[1]}"
              ENTRY_TITLE="${BASH_REMATCH[3]}"
              return 0
            fi
            return 1
          }

          author_suffix() {
            local login="$1"
            local profile="$2"
            local name="$3"
            if [ -n "$login" ]; then
              printf ' by [@%s](%s)' "$login" "${profile:-https://github.com/${login}}"
            elif [ -n "$name" ]; then
              printf ' by %s' "$name"
            fi
          }

          # %H = hash, %s = subject (first line)
          while IFS= read -r line; do
            [ -z "$line" ] && continue
            sha="${line%%$'\t'*}"
            subject="${line#*$'\t'}"

            commit_login="$(gh api "repos/${REPO}/commits/${sha}" --jq '.author.login // empty')"
            commit_name="$(gh api "repos/${REPO}/commits/${sha}" --jq '.commit.author.name // empty')"
            commit_profile=""
            if [ -n "$commit_login" ]; then
              commit_profile="$(gh api "repos/${REPO}/commits/${sha}" --jq '.author.html_url // empty')"
            fi

            pr="$(gh api "repos/${REPO}/commits/${sha}/pulls" --jq '.[0].number // empty')"
            if [ -z "$pr" ] && parse_conventional "$subject"; then
              short="${sha:0:7}"
              url="https://github.com/${REPO}/commit/${sha}"
              entry="- ${ENTRY_TITLE} ([\`${short}\`](${url}))"
              entry="${entry}$(author_suffix "$commit_login" "$commit_profile" "$commit_name")"
              if [ "$ENTRY_TYPE" = "feat" ]; then
                FEATS="${FEATS}${entry}"$'\n'
              elif [ "$ENTRY_TYPE" = "fix" ]; then
                FIXES="${FIXES}${entry}"$'\n'
              fi
            fi
          done < <(git log "$RANGE" --format="%H%x09%s" --no-merges)

          {
            echo "# ${TAG}"
            echo ""
            if [ -n "$FEATS" ]; then
              echo "## Features"
              echo ""
              printf "%s" "$FEATS"
              echo ""
            fi
            if [ -n "$FIXES" ]; then
              echo "## Fixes"
              echo ""
              printf "%s" "$FIXES"
              echo ""
            fi
            if [ -z "$FEATS" ] && [ -z "$FIXES" ]; then
              echo "_No relevant conventional commits (feat/fix) in this release._"
              echo ""
            fi
            echo "---"
            echo ""
            if [ -n "$PREV_TAG" ]; then
              echo "**Full diff:** [\`${PREV_TAG}...${TAG}\`](https://github.com/${REPO}/compare/${PREV_TAG}...${TAG})"
            else
              echo "**Full history up to ${TAG}**"
            fi
          } > /tmp/notes.md

          cat /tmp/notes.md
          # multiline output for next step
          {
            echo "notes<<EOF"
            cat /tmp/notes.md
            echo "EOF"
          } >> "$GITHUB_OUTPUT"

      - name: Create GitHub Release
        uses: softprops/action-gh-release@v2
        with:
          tag_name: ${{ github.ref_name }}
          name: ${{ github.ref_name }}
          body: ${{ steps.changelog.outputs.notes }}
          generate_release_notes: true