migrate_to_codeberg.sh

#!/bin/bash

# === INPUT CHECK ===
if [ -z "$1" ]; then
  echo "❌ Usage: ./migrate.sh <GitHub repo URL>"
  echo "   Example: ./migrate.sh https://github.com/username/repo"
  echo "            ./migrate.sh git@github.com:username/repo.git"
  exit 1
fi


# === USER CONFIGURATION ===
CODEBERG_USERNAME="YOUR_CODEBERG_USERNAME"  # e.g., "joergi"
CODEBERG_TOKEN="YOUR_CODEBERG_TOKEN"  # Generate at https://codeberg.org/user/settings/applications
GITHUB_EMAIL="YOUR_GITHUB_EMAIL@email.com"  # 123456789+YOUR_GITHUB_USERNAME@users.noreply.github.com"
CODEBERG_NAME="YOUR_CODEBERG_NAME"  # e.g., "joergi"
CODEBERG_EMAIL="YOUR_CODEBERG_EMAIL@email.com"  # e.g., "your.email@example.com"
GITHUB_BASE="/home/username/folder/for/github/repos

# === PARSE INPUT ===
INPUT="$1"

if [[ "$INPUT" == https://github.com/* ]]; then
  GITHUB_USER=$(echo "$INPUT" | cut -d'/' -f4)
  REPO_NAME=$(echo "$INPUT" | cut -d'/' -f5)
elif [[ "$INPUT" == git@github.com:* ]]; then
  GITHUB_USER=$(echo "$INPUT" | cut -d':' -f2 | cut -d'/' -f1)
  REPO_NAME=$(echo "$INPUT" | cut -d'/' -f2 | sed 's/.git$//')
else
  echo "❌ Unsupported GitHub URL format."
  exit 1
fi

GITHUB_REPO_SSH="git@github.com:$GITHUB_USER/$REPO_NAME.git"
GITHUB_EMAIL="$GITHUB_USER@users.noreply.github.com"
GITHUB_DIR="$GITHUB_BASE/$REPO_NAME.git"
CODEBERG_REPO_SSH="git@codeberg.org:$CODEBERG_USERNAME/$REPO_NAME.git"

# === SAFETY CHECK ===
echo "⚠️ This script rewrites Git history and force-pushes to Codeberg."
echo "   It will clone from: $GITHUB_REPO_SSH"
echo "   and push to:        $CODEBERG_REPO_SSH"
read -p "Proceed with migration? (y/n): " CONFIRM
if [[ "$CONFIRM" != "y" ]]; then
  echo "❌ Aborted."
  exit 1
fi

# === CREATE REPO ON CODEBERG ===
echo "🆕 Creating repository '$REPO_NAME' on Codeberg..."
curl -s -X POST "https://codeberg.org/api/v1/user/repos" \
  -H "Content-Type: application/json" \
  -H "Authorization: token $CODEBERG_TOKEN" \
  -d "{\"name\":\"$REPO_NAME\",\"private\":false,\"auto_init\":false}" > /dev/null

# === CLONE FROM GITHUB ===
echo "📦 Cloning GitHub repo into $GITHUB_DIR..."
git clone --mirror "$GITHUB_REPO_SSH" "$GITHUB_DIR"
cd "$GITHUB_DIR" || exit

# === REWRITE HISTORY ===
echo "🛠️ Rewriting commit history..."
git filter-branch --env-filter "
if [ \"\$GIT_COMMITTER_EMAIL\" = \"$GITHUB_EMAIL\" ]; then
    export GIT_COMMITTER_NAME=\"$CODEBERG_NAME\"
    export GIT_COMMITTER_EMAIL=\"$CODEBERG_EMAIL\"
fi
if [ \"\$GIT_AUTHOR_EMAIL\" = \"$GITHUB_EMAIL\" ]; then
    export GIT_AUTHOR_NAME=\"$CODEBERG_NAME\"
    export GIT_AUTHOR_EMAIL=\"$CODEBERG_EMAIL\"
fi
" --tag-name-filter cat -- --all

# === CLEANUP ===
echo "🧹 Cleaning up backup refs..."
rm -rf refs/original/
git reflog expire --expire=now --all
git gc --prune=now --aggressive

# === PUSH TO CODEBERG ===
echo "🚀 Pushing to Codeberg via SSH..."
git remote set-url origin "$CODEBERG_REPO_SSH"
git push --mirror --force

echo "✅ Migration complete! '$REPO_NAME' is now live on Codeberg with your updated identity."
echo "   👉 https://codeberg.org/$CODEBERG_USERNAME/$REPO_NAME"