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# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
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#
#     http://www.apache.org/licenses/LICENSE-2.0
#
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# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

name: Assign/unassign the issue via `take` or `untake` comment
on:
  issue_comment:
    types: created

permissions:
  issues: write

jobs:
  issue_assign:
    runs-on: ubuntu-slim
    if: (!github.event.issue.pull_request) && (github.event.comment.body == 'take' || github.event.comment.body == 'untake')
    concurrency:
      group: ${{ github.workflow }}-${{ github.event.issue.number }}
      queue: max
    steps:
      - name: Take or untake issue
        env:
          COMMENT_BODY: ${{ github.event.comment.body }}
          ISSUE_NUMBER: ${{ github.event.issue.number }}
          USER_LOGIN: ${{ github.event.comment.user.login }}
          REPO: ${{ github.repository }}
          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
        shell: bash
        run: |
          set -euo pipefail

          API_VERSION="2026-03-10"
          ISSUE_ENDPOINT="repos/$REPO/issues/$ISSUE_NUMBER"
          ASSIGNEES_ENDPOINT="$ISSUE_ENDPOINT/assignees"
          COMMENTS_ENDPOINT="$ISSUE_ENDPOINT/comments"

          post_comment() {
            local body="$1"
            gh api --silent \
              --method POST \
              --header "X-GitHub-Api-Version: $API_VERSION" \
              "$COMMENTS_ENDPOINT" \
              --raw-field "body=$body"
          }

          reply() {
            local body="$1"
            echo "$body"
            post_comment "$body"
          }

          fail_with_comment() {
            local body="$1"
            echo "$body" >&2
            if ! post_comment "$body"; then
              echo "Could not post the failure message to issue $ISSUE_NUMBER" >&2
            fi
            exit 1
          }

          if [[ "$COMMENT_BODY" == "take" ]]; then
            if ! CURRENT_ASSIGNEES="$(
              gh api \
                --header "X-GitHub-Api-Version: $API_VERSION" \
                "$ISSUE_ENDPOINT" \
                --jq '[.assignees[].login]'
            )"; then
              fail_with_comment \
                "I could not inspect the current assignees. Please try again later."
            fi

            if jq -e --arg user "$USER_LOGIN" \
              'any(.[]; . != $user)' <<<"$CURRENT_ASSIGNEES" >/dev/null; then
              CURRENT_HOLDERS="$(
                jq -r --arg user "$USER_LOGIN" \
                  '[.[] | select(. != $user)] | join(", ")' \
                  <<<"$CURRENT_ASSIGNEES"
              )"
              reply \
                "Issue #$ISSUE_NUMBER is already assigned to $CURRENT_HOLDERS, so it was not reassigned."
              exit 0
            fi

            if jq -e --arg user "$USER_LOGIN" \
              'index($user) != null' <<<"$CURRENT_ASSIGNEES" >/dev/null; then
              echo "Issue #$ISSUE_NUMBER is already assigned to $USER_LOGIN."
              exit 0
            fi

            echo "Assigning issue $ISSUE_NUMBER to $USER_LOGIN"
            if ! ASSIGNMENT_RESPONSE="$(
              gh api \
                --method POST \
                --header "X-GitHub-Api-Version: $API_VERSION" \
                "$ASSIGNEES_ENDPOINT" \
                --field "assignees[]=$USER_LOGIN"
            )"; then
              fail_with_comment \
                "I could not assign this issue because the GitHub API request failed. Please try again later."
            fi

            if ! jq -e '.assignees | type == "array"' \
              <<<"$ASSIGNMENT_RESPONSE" >/dev/null; then
              fail_with_comment \
                "I could not verify the new assignee. Please try again later."
            fi

            if ! jq -e --arg user "$USER_LOGIN" \
              '.assignees | map(.login) | index($user) != null' \
              <<<"$ASSIGNMENT_RESPONSE" >/dev/null; then
              reply \
                "GitHub did not add $USER_LOGIN as an assignee. The account may not be assignable in this repository."
              exit 0
            fi

            if ! jq -e --arg user "$USER_LOGIN" \
              '.assignees | length == 1 and .[0].login == $user' \
              <<<"$ASSIGNMENT_RESPONSE" >/dev/null; then
              CURRENT_HOLDERS="$(
                jq -r --arg user "$USER_LOGIN" \
                  '[.assignees[].login | select(. != $user)] | join(", ")' \
                  <<<"$ASSIGNMENT_RESPONSE"
              )"

              if ! ROLLBACK_RESPONSE="$(
                gh api \
                  --method DELETE \
                  --header "X-GitHub-Api-Version: $API_VERSION" \
                  "$ASSIGNEES_ENDPOINT" \
                  --field "assignees[]=$USER_LOGIN"
              )"; then
                fail_with_comment \
                  "Another assignee appeared while take was running, and I could not undo the conflicting assignment."
              fi

              if ! jq -e --arg user "$USER_LOGIN" \
                '.assignees | type == "array" and (map(.login) | index($user) == null)' \
                <<<"$ROLLBACK_RESPONSE" >/dev/null; then
                fail_with_comment \
                  "Another assignee appeared while take was running, and I could not verify that the conflicting assignment was undone."
              fi

              reply \
                "Issue #$ISSUE_NUMBER was assigned to $CURRENT_HOLDERS while take was running, so it was not reassigned."
              exit 0
            fi
          elif [[ "$COMMENT_BODY" == "untake" ]]; then
            echo "Unassigning issue $ISSUE_NUMBER from $USER_LOGIN"
            if ! UNASSIGNMENT_RESPONSE="$(
              gh api \
                --method DELETE \
                --header "X-GitHub-Api-Version: $API_VERSION" \
                "$ASSIGNEES_ENDPOINT" \
                --field "assignees[]=$USER_LOGIN"
            )"; then
              fail_with_comment \
                "I could not unassign this issue because the GitHub API request failed. Please try again later."
            fi

            if ! jq -e --arg user "$USER_LOGIN" \
              '.assignees | type == "array" and (map(.login) | index($user) == null)' \
              <<<"$UNASSIGNMENT_RESPONSE" >/dev/null; then
              fail_with_comment \
                "I could not verify that $USER_LOGIN was unassigned. Please try again later."
            fi
          fi