#!/usr/bin/env sh
set -euo pipefail

remote=`git remote |head -1`
repoNwo=`git remote get-url $remote | sed 's/.*://;s/\.git//'`
repoNodeId=`gh api repos/$repoNwo --jq '.node_id'`
branch=`git rev-parse --abbrev-ref HEAD`
newBranch="new-branch-$RANDOM"
contents=`echo -e 'Hello, GraphQL!\n' | base64`
expectedHeadOid=`git rev-parse HEAD`

curl https://api.github.com/graphql --silent \
     -H "Authorization: bearer $TOKEN" \
     -H "Accept: application/vnd.github.update-refs-preview+json" \
     --data @- <<GRAPHQL | jq
{
  "query": "mutation (\$refsInput: UpdateRefsInput!, \$commitInput: CreateCommitOnBranchInput!) {
    updateRefs(input: \$refsInput) {
      clientMutationId
    }
    createCommitOnBranch(input: \$commitInput) { 
      commit { 
        url 
      } 
    } 
  }",
  "variables": {
    "refsInput": {
      "clientMutationId": "create-$newBranch-at-$expectedHeadOid",
      "repositoryId": "$repoNodeId",
      "refUpdates": [
        {
          "name": "refs/heads/$newBranch",
          "beforeOid": "0000000000000000000000000000000000000000",
          "afterOid": "$expectedHeadOid"
        }
      ]
    },
    "commitInput": {
      "branch": {
        "repositoryNameWithOwner": "$repoNwo",
        "branchName": "$newBranch"
      },
      "message": { "headline": "Hello from GraphQL!" },
      "fileChanges": {
        "additions": [
          {
            "path": "GraphQL-$RANDOM.md",
            "contents": "$contents"
          }
        ]
      },
      "expectedHeadOid": "$expectedHeadOid"
    }
  }
}
GRAPHQL