install.sh

#!/bin/bash
set -euo pipefail

# remote-input-sync installer
# Syncs input source (Korean/English) between local and remote Mac over Screen Sharing
#
# Usage:
#   curl -fsSL https://raw.githubusercontent.com/firejune/remote-input-sync/main/install.sh | bash -s
#
# Or download and run:
#   curl -fsSL https://raw.githubusercontent.com/firejune/remote-input-sync/main/install.sh -o install.sh
#   bash install.sh

REPO_RAW="https://raw.githubusercontent.com/firejune/remote-input-sync/main"
INSTALL_DIR="$HOME/bin"
ISSW_PATH="$INSTALL_DIR/issw"
TOGGLE_PATH="$INSTALL_DIR/toggle_input_sync.sh"

RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
CYAN='\033[0;36m'
BOLD='\033[1m'
NC='\033[0m'

info()  { echo -e "${CYAN}▸${NC} $1"; }
ok()    { echo -e "${GREEN}✔${NC} $1"; }
warn()  { echo -e "${YELLOW}⚠${NC} $1"; }
fail()  { echo -e "${RED}✖${NC} $1"; exit 1; }

# Ensure stdin is from terminal (fixes curl | bash breaking read)
if [[ ! -t 0 ]]; then
    exec < /dev/tty || fail "Cannot read user input. Download and run the script manually:\n  curl -fsSL $REPO_RAW/install.sh -o install.sh && bash install.sh"
fi

echo ""
echo -e "${BOLD}╔══════════════════════════════════════════╗${NC}"
echo -e "${BOLD}║   remote-input-sync installer            ║${NC}"
echo -e "${BOLD}║   Sync input source over Screen Sharing  ║${NC}"
echo -e "${BOLD}╚══════════════════════════════════════════╝${NC}"
echo ""

# -----------------------------------------------------------
# 1. Prerequisites
# -----------------------------------------------------------
info "Checking prerequisites..."

if [[ "$(uname)" != "Darwin" ]]; then
    fail "This tool only works on macOS."
fi

if ! command -v swiftc &>/dev/null; then
    fail "Swift compiler not found. Install Xcode Command Line Tools:\n  xcode-select --install"
fi

if ! command -v python3 &>/dev/null; then
    fail "python3 not found. It is required for Karabiner configuration."
fi

if ! command -v curl &>/dev/null; then
    fail "curl not found."
fi

if [[ ! -d "$HOME/.config/karabiner" ]]; then
    warn "Karabiner-Elements not found."
    echo -e "  Install it first: ${CYAN}https://karabiner-elements.pqrs.org${NC}"
    echo -e "  Then re-run this installer."
    exit 1
fi

if [[ ! -f "$HOME/.config/karabiner/karabiner.json" ]]; then
    fail "karabiner.json not found. Open Karabiner-Elements once to generate the default config."
fi

ok "Prerequisites OK"

# -----------------------------------------------------------
# 2. Remote host
# -----------------------------------------------------------
echo ""
info "Enter the remote Mac hostname (e.g. My-Mac-mini.local):"
read -rp "  Hostname: " REMOTE_HOSTNAME

if [[ -z "$REMOTE_HOSTNAME" ]]; then
    fail "Hostname is required."
fi

info "Enter the SSH username for ${BOLD}${REMOTE_HOSTNAME}${NC} (default: $(whoami)):"
read -rp "  Username [$(whoami)]: " REMOTE_USER
REMOTE_USER="${REMOTE_USER:-$(whoami)}"
REMOTE_HOST="${REMOTE_USER}@${REMOTE_HOSTNAME}"

echo ""
ok "Remote: ${BOLD}${REMOTE_HOST}${NC}"

# -----------------------------------------------------------
# 3. Input toggle key
# -----------------------------------------------------------
echo ""
info "Which key do you use for input source switching?"
echo ""
echo -e "  ${BOLD}1)${NC} ⌘ Cmd + Space  ${YELLOW}(legacy macOS)${NC}"
echo -e "  ${BOLD}2)${NC} ⌃ Ctrl + Space  ${YELLOW}(default macOS)${NC}"
echo -e "  ${BOLD}3)${NC} 🌐 Fn / Globe key"
echo ""
read -rp "  Choose [1/2/3]: " KEY_CHOICE

case "$KEY_CHOICE" in
    1) KEY_DESC="Cmd + Space"
       KARABINER_FROM='{ "key_code": "spacebar", "modifiers": { "mandatory": ["command"], "optional": ["any"] } }' ;;
    2) KEY_DESC="Ctrl + Space"
       KARABINER_FROM='{ "key_code": "spacebar", "modifiers": { "mandatory": ["control"], "optional": ["any"] } }' ;;
    3) KEY_DESC="Fn / Globe"
       KARABINER_FROM='{ "apple_vendor_keyboard_key_code": "function" }' ;;
    *) fail "Invalid choice. Please enter 1, 2, or 3." ;;
esac

ok "Toggle key: ${BOLD}${KEY_DESC}${NC}"

# -----------------------------------------------------------
# 4. Build issw locally
# -----------------------------------------------------------
echo ""
info "Building issw..."
mkdir -p "$INSTALL_DIR"

SWIFT_SRC=$(mktemp /tmp/issw_XXXXXX.swift)
trap 'rm -f "$SWIFT_SRC"' EXIT

if ! curl -fsSL "$REPO_RAW/src/issw.swift" -o "$SWIFT_SRC"; then
    fail "Failed to download issw.swift. Check your internet connection."
fi

if ! swiftc -O "$SWIFT_SRC" -framework Carbon -o "$ISSW_PATH"; then
    fail "Failed to compile issw. Check your Swift compiler."
fi

chmod +x "$ISSW_PATH"
ok "Installed: ${BOLD}${ISSW_PATH}${NC}"

# -----------------------------------------------------------
# 5. Detect input sources
# -----------------------------------------------------------
info "Detecting input sources..."
if CURRENT=$("$ISSW_PATH"); then
    ok "Current input source: ${BOLD}${CURRENT}${NC}"
else
    warn "Could not detect input source (may work fine after reboot)"
fi

# -----------------------------------------------------------
# 6. Install toggle script
# -----------------------------------------------------------
info "Installing toggle script..."
TOGGLE_SRC=$(mktemp /tmp/toggle_XXXXXX.sh)

if ! curl -fsSL "$REPO_RAW/toggle_input_sync.sh" -o "$TOGGLE_SRC"; then
    rm -f "$TOGGLE_SRC"
    fail "Failed to download toggle script."
fi

sed "s|__REMOTE_HOST__|${REMOTE_HOST}|g" "$TOGGLE_SRC" > "$TOGGLE_PATH"
rm -f "$TOGGLE_SRC"

chmod +x "$TOGGLE_PATH"
ok "Installed: ${BOLD}${TOGGLE_PATH}${NC}"

# -----------------------------------------------------------
# 7. SSH key setup
# -----------------------------------------------------------
echo ""
info "Checking SSH key authentication..."

if ssh -o ConnectTimeout=5 -o BatchMode=yes "$REMOTE_HOST" 'echo ok' &>/dev/null; then
    ok "SSH key auth already configured"
else
    warn "SSH key auth not set up for ${REMOTE_HOST}"

    if [[ ! -f "$HOME/.ssh/id_ed25519.pub" ]] && [[ ! -f "$HOME/.ssh/id_rsa.pub" ]]; then
        info "Generating SSH key..."
        mkdir -p "$HOME/.ssh"
        chmod 700 "$HOME/.ssh"
        ssh-keygen -t ed25519 -f "$HOME/.ssh/id_ed25519" -N "" -q
    fi

    # Use whichever key exists
    SSH_PUB_KEY=""
    if [[ -f "$HOME/.ssh/id_ed25519.pub" ]]; then
        SSH_PUB_KEY="$HOME/.ssh/id_ed25519.pub"
    elif [[ -f "$HOME/.ssh/id_rsa.pub" ]]; then
        SSH_PUB_KEY="$HOME/.ssh/id_rsa.pub"
    fi

    info "Copying SSH key to ${REMOTE_HOST}..."
    echo -e "  ${YELLOW}You may be prompted for the remote Mac's password.${NC}"

    if ! ssh-copy-id -i "$SSH_PUB_KEY" "$REMOTE_HOST"; then
        fail "Failed to copy SSH key. Make sure:\n  1. Remote Login is enabled on the remote Mac (System Settings → General → Sharing)\n  2. The hostname and username are correct"
    fi

    if ssh -o ConnectTimeout=5 -o BatchMode=yes "$REMOTE_HOST" 'echo ok' &>/dev/null; then
        ok "SSH key auth configured"
    else
        fail "SSH key auth verification failed. Check your credentials and try again."
    fi
fi

# -----------------------------------------------------------
# 8. Build issw on remote
# -----------------------------------------------------------
echo ""
info "Building issw on remote Mac..."

# Check remote has swiftc
if ! ssh -o ConnectTimeout=5 "$REMOTE_HOST" 'command -v swiftc' &>/dev/null; then
    fail "Swift compiler not found on remote Mac.\n  Run on the remote Mac: xcode-select --install"
fi

if ! curl -fsSL "$REPO_RAW/src/issw.swift" | ssh "$REMOTE_HOST" 'cat > /tmp/issw_build.swift && mkdir -p ~/bin && swiftc -O /tmp/issw_build.swift -framework Carbon -o ~/bin/issw && rm /tmp/issw_build.swift'; then
    fail "Failed to build issw on remote Mac."
fi

REMOTE_CURRENT=$(ssh -o ConnectTimeout=5 "$REMOTE_HOST" '~/bin/issw' 2>/dev/null || echo "unknown")
ok "Remote issw installed (current: ${BOLD}${REMOTE_CURRENT}${NC})"

# -----------------------------------------------------------
# 9. Karabiner configuration
# -----------------------------------------------------------
echo ""
info "Configuring Karabiner-Elements..."

KARABINER_CONFIG="$HOME/.config/karabiner/karabiner.json"
BACKUP="$HOME/.config/karabiner/karabiner.json.backup.$(date +%s)"
cp "$KARABINER_CONFIG" "$BACKUP"
ok "Config backed up: ${BOLD}${BACKUP##*/}${NC}"

# Build the new rule JSON
NEW_RULE=$(cat <<EOF
{
    "description": "remote-input-sync: Sync input source with remote Mac (${KEY_DESC})",
    "manipulators": [
        {
            "conditions": [
                {
                    "bundle_identifiers": ["^com\\\\.apple\\\\.ScreenSharing$"],
                    "type": "frontmost_application_if"
                }
            ],
            "from": ${KARABINER_FROM},
            "to": [
                {
                    "shell_command": "${TOGGLE_PATH}"
                }
            ],
            "type": "basic"
        }
    ]
}
EOF
)

# Insert the rule using python3 (ships with macOS)
if ! python3 - "$KARABINER_CONFIG" "$NEW_RULE" <<'PYEOF'
import json, sys

config_path = sys.argv[1]
new_rule = json.loads(sys.argv[2])

with open(config_path, 'r') as f:
    config = json.load(f)

# Ensure structure exists
profiles = config.get('profiles', [])
if not profiles:
    print("Error: no profiles found in karabiner.json", file=sys.stderr)
    sys.exit(1)

profile = profiles[0]
complex_mods = profile.setdefault('complex_modifications', {})
rules = complex_mods.setdefault('rules', [])

# Remove existing remote-input-sync rules
rules[:] = [r for r in rules if not r.get('description', '').startswith('remote-input-sync:')]
rules.insert(0, new_rule)

with open(config_path, 'w') as f:
    json.dump(config, f, indent=4, ensure_ascii=False)
PYEOF
then
    warn "Failed to update Karabiner config. Restoring backup..."
    cp "$BACKUP" "$KARABINER_CONFIG"
    fail "Karabiner configuration failed. You can manually add the rule."
fi

ok "Karabiner rule added"

# -----------------------------------------------------------
# 10. PATH check
# -----------------------------------------------------------
echo ""
if [[ ":$PATH:" != *":$HOME/bin:"* ]]; then
    warn "\$HOME/bin is not in your PATH."
    echo -e "  Add this to your shell profile (~/.zshrc):"
    echo -e "  ${CYAN}export PATH=\"\$HOME/bin:\$PATH\"${NC}"
    echo ""
fi

# -----------------------------------------------------------
# Done!
# -----------------------------------------------------------
echo ""
echo -e "${GREEN}${BOLD}✔ Installation complete!${NC}"
echo ""
echo -e "  ${BOLD}How it works:${NC}"
echo -e "  1. Open Screen Sharing and connect to ${BOLD}${REMOTE_HOSTNAME}${NC}"
echo -e "  2. Press ${BOLD}${KEY_DESC}${NC} to toggle input source"
echo -e "  3. Both local and remote will switch in sync"
echo ""
echo -e "  ${BOLD}To uninstall:${NC}"
echo -e "  ${CYAN}rm ~/bin/issw ~/bin/toggle_input_sync.sh${NC}"
echo -e "  Then remove the rule from Karabiner-Elements preferences."
echo ""