setup-git.sh

#!/usr/bin/env bash
# git-setup.sh — Interactive Git setup using charmbracelet/gum
# Usage: bash git-setup.sh

set -euo pipefail

# ─── Colors & styles ────────────────────────────────────────────────────────
BOLD="--foreground 212 --bold"

# ─── Check dependencies ──────────────────────────────────────────────────────
check_deps() {
  for cmd in git gum; do
    if ! command -v "$cmd" &>/dev/null; then
      echo "❌ '$cmd' is required but not installed."
      if [[ "$cmd" == "gum" ]]; then
        echo "Install gum: https://github.com/charmbracelet/gum#installation"
      fi
      exit 1
    fi
  done
}

# ─── Header ──────────────────────────────────────────────────────────────────
print_header() {
  gum style \
    --foreground 212 --border-foreground 212 --border double \
    --align center --width 50 --margin "1 2" --padding "1 4" \
    '🔧 Git Setup Wizard' \
    'Configure your new machine for Git'
}

# ─── Identity ────────────────────────────────────────────────────────────────
setup_identity() {
  gum style --foreground 99 --bold "── Identity ──────────────────────────"

  local current_name current_email
  current_name=$(git config --global user.name 2>/dev/null || echo "")
  current_email=$(git config --global user.email 2>/dev/null || echo "")

  local name
  name=$(gum input \
    --placeholder "Your full name" \
    --value "$current_name" \
    --prompt "👤 Name: ")
  [[ -z "$name" ]] && { gum style --foreground 196 "Name cannot be empty."; exit 1; }

  local email
  email=$(gum input \
    --placeholder "you@example.com" \
    --value "$current_email" \
    --prompt "📧 Email: ")
  [[ -z "$email" ]] && { gum style --foreground 196 "Email cannot be empty."; exit 1; }

  git config --global user.name  "$name"
  git config --global user.email "$email"
  gum style --foreground 82 "✔ Identity set: $name <$email>"
}

# ─── Default branch ──────────────────────────────────────────────────────────
setup_default_branch() {
  gum style --foreground 99 --bold "── Default Branch ────────────────────"

  local current
  current=$(git config --global init.defaultBranch 2>/dev/null || echo "main")

  local branch
  branch=$(gum choose --selected "$current" "main" "master" "trunk" "develop" "(custom)")

  if [[ "$branch" == "(custom)" ]]; then
    branch=$(gum input --placeholder "branch-name" --prompt "🌿 Branch name: ")
  fi

  [[ -z "$branch" ]] && branch="main"
  git config --global init.defaultBranch "$branch"
  gum style --foreground 82 "✔ Default branch: $branch"
}

# ─── Editor ──────────────────────────────────────────────────────────────────
setup_editor() {
  gum style --foreground 99 --bold "── Default Editor ────────────────────"

  local current
  current=$(git config --global core.editor 2>/dev/null || echo "")

  local editor
  editor=$(gum choose --selected "${current:-vim}" \
    "vim" "nvim" "nano" "emacs" "code --wait" "hx" "(custom)")

  if [[ "$editor" == "(custom)" ]]; then
    editor=$(gum input --placeholder "e.g. micro" --prompt "✏️  Editor: ")
  fi

  [[ -z "$editor" ]] && editor="vim"
  git config --global core.editor "$editor"
  gum style --foreground 82 "✔ Editor: $editor"
}

# ─── GPG signing ─────────────────────────────────────────────────────────────
setup_gpg() {
  gum style --foreground 99 --bold "── GPG Commit Signing ────────────────"

  if ! gum confirm "Enable GPG commit signing?"; then
    gum style --foreground 243 "⏭  Skipped GPG signing."
    return
  fi

  if ! command -v gpg &>/dev/null; then
    gum style --foreground 196 "gpg not found — skipping GPG setup."
    return
  fi

  # List available keys
  local keys
  keys=$(gpg --list-secret-keys --keyid-format=long 2>/dev/null \
    | grep '^sec' | awk '{print $2}' | cut -d'/' -f2 || true)

  local signing_key
  if [[ -z "$keys" ]]; then
    gum style --foreground 214 "No GPG keys found. Generate one with: gpg --full-generate-key"
    signing_key=$(gum input --placeholder "Paste your GPG key ID" --prompt "🔑 Key ID: ")
  else
    signing_key=$(echo "$keys" | gum choose --header "Select your signing key:")
  fi

  if [[ -n "$signing_key" ]]; then
    git config --global user.signingkey  "$signing_key"
    git config --global commit.gpgsign   true
    git config --global tag.gpgSign      true
    gum style --foreground 82 "✔ GPG signing enabled with key: $signing_key"
  fi
}

# ─── SSH key ─────────────────────────────────────────────────────────────────
setup_ssh() {
  gum style --foreground 99 --bold "── SSH Key ───────────────────────────"

  # Check for existing keys
  local existing=()
  for f in ~/.ssh/id_ed25519 ~/.ssh/id_rsa ~/.ssh/id_ecdsa; do
    [[ -f "$f" ]] && existing+=("$f")
  done

  if [[ ${#existing[@]} -gt 0 ]]; then
    gum style --foreground 82 "Existing SSH keys found:"
    for k in "${existing[@]}"; do
      gum style --foreground 243 "  • $k"
    done
    if ! gum confirm "Generate a new SSH key anyway?"; then
      gum style --foreground 243 "⏭  Using existing SSH key."
      return
    fi
  fi

  local key_type
  key_type=$(gum choose --selected "ed25519" "ed25519" "rsa" --header "Key type:")

  local key_path="$HOME/.ssh/id_${key_type}"
  local comment
  comment=$(git config --global user.email 2>/dev/null || echo "")
  comment=$(gum input --value "$comment" --prompt "💬 Key comment: ")

  if [[ "$key_type" == "rsa" ]]; then
    ssh-keygen -t rsa -b 4096 -C "$comment" -f "$key_path"
  else
    ssh-keygen -t ed25519 -C "$comment" -f "$key_path"
  fi

  # Start ssh-agent and add key
  eval "$(ssh-agent -s)" &>/dev/null
  ssh-add "$key_path" 2>/dev/null || true

  gum style --foreground 82 "✔ SSH key generated: ${key_path}.pub"
  gum style --foreground 214 "📋 Copy this public key to GitHub/GitLab:"
  gum style --border normal --padding "0 1" "$(cat "${key_path}.pub")"
}

# ─── Useful aliases ──────────────────────────────────────────────────────────
setup_aliases() {
  gum style --foreground 99 --bold "── Git Aliases ───────────────────────"

  declare -A ALIASES=(
    [st]="status -sb"
    [co]="checkout"
    [br]="branch"
    [lg]="log --oneline --graph --decorate --all"
    [last]="log -1 HEAD --stat"
    [undo]="reset HEAD~1 --mixed"
    [aliases]="config --get-regexp alias"
    [pushf]="push --force-with-lease"
    [stash-all]="stash save --include-untracked"
  )

  local selected
  selected=$(printf '%s\n' "${!ALIASES[@]}" | sort | \
    gum choose --no-limit --header "Select aliases to install (space to toggle):")

  if [[ -z "$selected" ]]; then
    gum style --foreground 243 "⏭  No aliases selected."
    return
  fi

  while IFS= read -r alias_name; do
    git config --global "alias.${alias_name}" "${ALIASES[$alias_name]}"
    gum style --foreground 82 "  ✔ git $alias_name → ${ALIASES[$alias_name]}"
  done <<< "$selected"
}

# ─── Extra quality-of-life settings ─────────────────────────────────────────
setup_extras() {
  gum style --foreground 99 --bold "── Extra Settings ────────────────────"

  declare -A EXTRAS=(
    ["Auto-correct typos (autocorrect=10)"]="core.autocorrect|10"
    ["Color UI always on"]="color.ui|always"
    ["Push current branch only (simple)"]="push.default|simple"
    ["Pull rebase by default"]="pull.rebase|true"
    ["Rebase autostash"]="rebase.autoStash|true"
    ["Rerere (reuse recorded resolutions)"]="rerere.enabled|true"
    ["Prune on fetch"]="fetch.prune|true"
    ["Diff algorithm: histogram"]="diff.algorithm|histogram"
    ["Merge tool: verbose conflict markers"]="merge.conflictstyle|diff3"
    ["Credential helper: store"]="credential.helper|store"
  )

  local selected
  selected=$(printf '%s\n' "${!EXTRAS[@]}" | sort | \
    gum choose --no-limit --header "Select extra settings to enable:")

  [[ -z "$selected" ]] && { gum style --foreground 243 "⏭  No extras selected."; return; }

  while IFS= read -r label; do
    local pair="${EXTRAS[$label]}"
    local key="${pair%%|*}"
    local val="${pair##*|}"
    git config --global "$key" "$val"
    gum style --foreground 82 "  ✔ $key = $val"
  done <<< "$selected"
}

# ─── Global .gitignore ───────────────────────────────────────────────────────
setup_gitignore() {
  gum style --foreground 99 --bold "── Global .gitignore ─────────────────"

  if ! gum confirm "Set up a global .gitignore?"; then
    gum style --foreground 243 "⏭  Skipped."
    return
  fi

  local ignore_file="$HOME/.gitignore_global"

  cat > "$ignore_file" <<'IGNORE'
# OS
.DS_Store
.DS_Store?
._*
.Spotlight-V100
.Trashes
Thumbs.db
ehthumbs.db
Desktop.ini

# Editors
.vscode/
.idea/
*.swp
*.swo
*~
.project
.classpath

# Secrets & env
.env
.env.*
!.env.example
*.pem
*.key
*.cert

# Logs & temp
*.log
*.tmp
*.bak
*.orig
npm-debug.log*
yarn-error.log*

# Build artifacts
dist/
build/
__pycache__/
*.pyc
*.pyo
node_modules/
.cache/
IGNORE

  git config --global core.excludesFile "$ignore_file"
  gum style --foreground 82 "✔ Global .gitignore created at $ignore_file"
}

# ─── Summary ─────────────────────────────────────────────────────────────────
print_summary() {
  gum style --foreground 99 --bold "── Final Configuration ───────────────"
  git config --global --list | sort | while IFS='=' read -r key val; do
    printf "  %-35s %s\n" "$key" "$val"
  done | gum pager
}

# ─── Main ────────────────────────────────────────────────────────────────────
main() {
  check_deps
  print_header

  gum style --foreground 243 "Choose which steps to run:"
  local steps
  steps=$(gum choose --no-limit \
    --selected "Identity,Default Branch,Editor,Aliases,Extra Settings,Global .gitignore" \
    "Identity" \
    "Default Branch" \
    "Editor" \
    "GPG Signing" \
    "SSH Key" \
    "Aliases" \
    "Extra Settings" \
    "Global .gitignore" \
    --header "Setup steps (space to toggle, enter to confirm):")

  echo ""

  [[ "$steps" == *"Identity"*          ]] && setup_identity
  [[ "$steps" == *"Default Branch"*    ]] && setup_default_branch
  [[ "$steps" == *"Editor"*            ]] && setup_editor
  [[ "$steps" == *"GPG Signing"*       ]] && setup_gpg
  [[ "$steps" == *"SSH Key"*           ]] && setup_ssh
  [[ "$steps" == *"Aliases"*           ]] && setup_aliases
  [[ "$steps" == *"Extra Settings"*    ]] && setup_extras
  [[ "$steps" == *"Global .gitignore"* ]] && setup_gitignore

  echo ""
  gum style \
    --foreground 82 --border-foreground 82 --border rounded \
    --align center --width 50 --padding "0 2" \
    "🎉 Git setup complete!"

  if gum confirm "View full git config?"; then
    print_summary
  fi
}

main "$@"