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

DOTFILES_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
DRY_RUN=false

for arg in "$@"; do
  [[ "$arg" == "--dry-run" ]] && DRY_RUN=true
done

$DRY_RUN && echo "[DRY RUN] No changes will be made."

run() {
  if $DRY_RUN; then
    echo "[DRY RUN] Would run: $*"
  else
    "$@"
  fi
}

step() { echo "==> $*"; }

# ---------------------------------------------------------------------------
# 1. Homebrew
# ---------------------------------------------------------------------------
step "Checking Homebrew"
if ! command -v brew &>/dev/null; then
  if $DRY_RUN; then
    echo "[DRY RUN] Would install Homebrew"
  else
    /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
  fi
fi

# ---------------------------------------------------------------------------
# 2. Install packages
# ---------------------------------------------------------------------------
step "Installing packages from Brewfile"
run brew bundle install --file="$DOTFILES_DIR/Brewfile" --no-lock

# ---------------------------------------------------------------------------
# 3. Set fish as default shell
# ---------------------------------------------------------------------------
step "Setting fish as default shell"
FISH_PATH="$(command -v fish || true)"
if [[ -z "$FISH_PATH" ]]; then
  echo "ERROR: fish not found after brew install — cannot set as default shell"
  exit 1
fi

if [[ "$SHELL" != "$FISH_PATH" ]]; then
  if ! grep -qF "$FISH_PATH" /etc/shells; then
    echo "Adding $FISH_PATH to /etc/shells (requires sudo)"
    run sudo sh -c "echo '$FISH_PATH' >> /etc/shells"
  fi
  run chsh -s "$FISH_PATH"
else
  echo "fish is already the default shell"
fi

# ---------------------------------------------------------------------------
# 4. Copy configs
# ---------------------------------------------------------------------------
CONFIGS=(
  "fish"
  "starship.toml"
  "nvim"
  "git"
  "herdr"
  "tmux"
  "aerospace"
  "ghostty"
)

step "Copying configs to ~/.config/"
for name in "${CONFIGS[@]}"; do
  src="$DOTFILES_DIR/.config/$name"
  dst="$HOME/.config/$name"

  if [[ ! -e "$src" ]]; then
    echo "  skip: $src not found in repo"
    continue
  fi

  if [[ -e "$dst" ]]; then
    if $DRY_RUN; then
      echo "[DRY RUN] Would backup $dst → ${dst}.bak"
      echo "[DRY RUN] Would copy $src → $dst"
    else
      echo "  backup: $dst → ${dst}.bak"
      rm -rf "${dst}.bak"
      cp -r "$dst" "${dst}.bak"
      rm -rf "$dst"
      cp -r "$src" "$dst"
    fi
  else
    if $DRY_RUN; then
      echo "[DRY RUN] Would copy $src → $dst"
    else
      echo "  copy: $src → $dst"
      cp -r "$src" "$dst"
    fi
  fi
done

# ---------------------------------------------------------------------------
# 5. tmux plugin manager (tpm)
# ---------------------------------------------------------------------------
step "Setting up tpm (tmux plugin manager)"
TPM_DIR="$HOME/.config/tmux/plugins/tpm"
if [[ ! -d "$TPM_DIR" ]]; then
  run git clone https://github.com/tmux-plugins/tpm "$TPM_DIR"
else
  echo "tpm already installed"
fi

echo ""
echo "Done. Open a new terminal to start using fish."
$DRY_RUN && echo "(This was a dry run — no changes were made.)"