#!/bin/bash

# Set your GitHub personal access token and organization name
ACCESS_TOKEN=""
ORG_NAME=""
NEW_DEFAULT_BRANCH="16.0"

if [[ -a ".env" && "$(cat .env | sed 's/^#.*//g')" ]]; then
    export $(cat .env | sed 's/^#.*//g' | xargs)
fi

# Check if the new default branch exists in the repository
check_branch_existence() {
    local repo_name=$1
    local branch=$2
    curl -s -o /dev/null -I -w "%{http_code}" -H "Authorization: token $ACCESS_TOKEN" \
        "https://api.github.com/repos/$ORG_NAME/$repo_name/branches/$branch"
}

# Get a list of repositories in the organization
REPOS=$(curl -s -H "Authorization: token $ACCESS_TOKEN" \
    "https://api.github.com/orgs/$ORG_NAME/repos?per_page=100")

# Loop through each repository in the organization
for repo in $(echo "$REPOS" | jq -r '.[] | @base64'); do
    name=$(echo "$repo" | base64 --decode | jq -r '.name')
    default_branch=$(echo "$repo" | base64 --decode | jq -r '.default_branch')

    # Check if the repository's default branch doesn't match the new default branch
    if [ "$default_branch" != "$NEW_DEFAULT_BRANCH" ]; then
        # Check if the new default branch exists in the repository
        if [ "$(check_branch_existence "$name" "$NEW_DEFAULT_BRANCH")" = "200" ]; then
            # Get the current default branch of the repository
            current_default_branch=$(curl -s -H "Authorization: token $ACCESS_TOKEN" \
                "https://api.github.com/repos/$ORG_NAME/$name" | jq -r '.default_branch')

            # Check if the current default branch matches the old default branch name

            echo "Updating default branch for '$name' to '$NEW_DEFAULT_BRANCH'..."
            curl -X PATCH -H "Authorization: token $ACCESS_TOKEN" \
                -H "Accept: application/vnd.github.v3+json" \
                -d "{\"default_branch\": \"$NEW_DEFAULT_BRANCH\"}" \
                "https://api.github.com/repos/$ORG_NAME/$name"

        else
            echo "New default branch '$NEW_DEFAULT_BRANCH' doesn't exist in '$name'. Skipping update."
        fi
    fi
done