#!/bin/bash
# setup_android_adblock.sh - Set up AdAway and systemless hosts on Android
set -euo pipefail

# Source common library
SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
# shellcheck source=../../lib/common.sh
source "$SCRIPT_DIR/../../lib/common.sh"
# shellcheck source=../../lib/android.sh
source "$SCRIPT_DIR/../../lib/android.sh"

# Initialize Android script (handles sudo, sets WORK_DIR)
init_android_script "$@"

install_adaway() {
  print_header "Installing AdAway"

  local adaway_apk="$WORK_DIR/adaway.apk"
  local adaway_url="https://github.com/AdAway/AdAway/releases/latest/download/AdAway.apk"

  if [[ ! -f $adaway_apk ]]; then
    log "Downloading AdAway APK..."
    curl -L -o "$adaway_apk" "$adaway_url" || die "Failed to download AdAway"
  else
    log "AdAway APK already downloaded"
  fi

  log "Installing AdAway..."
  if adb install -r "$adaway_apk" 2>&1 | grep -q "Success"; then
    log "AdAway installed successfully"
  else
    warn "AdAway installation may have failed or already installed"
  fi
}

setup_systemless_hosts() {
  print_header "Setting up Systemless Hosts"

  log "Installing Systemless Hosts module..."

  # Create systemless hosts module directory
  adb shell "su -c 'mkdir -p /data/adb/modules/systemless_hosts/system/etc'" || die "Failed to create module directory"

  # Create module.prop
  cat > "$WORK_DIR/module.prop" << 'EOF'
id=systemless_hosts
name=Systemless Hosts
version=1.0
versionCode=1
author=Custom
description=Custom hosts file from StevenBlack with extensions
EOF

  adb push "$WORK_DIR/module.prop" /sdcard/module.prop
  adb shell "su -c 'cp /sdcard/module.prop /data/adb/modules/systemless_hosts/'" || die "Failed to create module.prop"
  adb shell "su -c 'rm /sdcard/module.prop'"

  log "Module structure created"
}

push_hosts_file() {
  print_header "Pushing Custom Hosts File"

  local hosts_file="$WORK_DIR/hosts"

  # Use the StevenBlack cache or generate from /etc/hosts
  if [[ -f /etc/hosts.stevenblack ]]; then
    log "Using StevenBlack hosts cache..."
    cp /etc/hosts.stevenblack "$hosts_file"
  elif [[ -f /etc/hosts ]]; then
    log "Using current /etc/hosts..."
    cp /etc/hosts "$hosts_file"
  else
    die "No hosts file found"
  fi

  # Show stats
  local total_entries
  total_entries=$(grep -c "^0\.0\.0\.0 " "$hosts_file" || echo 0)
  log "Hosts file contains $total_entries blocked domains"

  log "Pushing hosts file to device..."
  adb push "$hosts_file" /sdcard/hosts || die "Failed to push hosts file"

  log "Installing hosts file systemlessly..."
  adb shell "su -c 'cp /sdcard/hosts /data/adb/modules/systemless_hosts/system/etc/hosts'" || die "Failed to install hosts file"
  adb shell "su -c 'chmod 644 /data/adb/modules/systemless_hosts/system/etc/hosts'" || die "Failed to set permissions"
  adb shell "su -c 'rm /sdcard/hosts'"

  log "Hosts file installed successfully"
  log "Total blocked domains: $total_entries"
}

enable_module() {
  print_header "Enabling Systemless Hosts Module"

  log "Removing disable flag if present..."
  adb shell "su -c 'rm -f /data/adb/modules/systemless_hosts/disable'" 2> /dev/null || true
  adb shell "su -c 'rm -f /data/adb/modules/systemless_hosts/remove'" 2> /dev/null || true

  log "Module enabled"

  echo
  echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
  echo "  REBOOT REQUIRED"
  echo "━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━"
  echo
  echo "The systemless hosts module requires a reboot to take effect."
  echo
  read -p "Reboot device now? [y/N]: " -n 1 -r
  echo

  if [[ $REPLY =~ ^[Yy]$ ]]; then
    log "Rebooting device..."
    adb reboot
    log "Device rebooting. Wait for boot to complete."
  else
    warn "Remember to reboot manually for changes to take effect!"
  fi
}

verify_hosts() {
  print_header "Verifying Hosts Installation"

  log "Waiting for device to boot..."
  sleep 5
  adb wait-for-device
  sleep 10

  log "Checking if hosts file is active..."
  local test_domain="doubleclick.net"
  local result
  result=$(adb shell "su -c 'cat /system/etc/hosts | grep -c $test_domain'" 2> /dev/null || echo "0")

  if [[ $result -gt 0 ]]; then
    log "✓ Hosts file is active and blocking domains"
  else
    warn "Could not verify hosts file, but module should be installed"
  fi
}

main() {
  print_header "Android Ad Blocking Setup"

  check_device
  check_root

  echo "This will:"
  echo "  1. Install AdAway app (optional GUI management)"
  echo "  2. Create systemless hosts module"
  echo "  3. Push your custom hosts file (StevenBlack with extensions)"
  echo "  4. Enable the module and reboot"
  echo
  read -p "Continue? [y/N]: " -n 1 -r
  echo

  if [[ ! $REPLY =~ ^[Yy]$ ]]; then
    log "Cancelled by user"
    exit 0
  fi

  install_adaway
  setup_systemless_hosts
  push_hosts_file
  enable_module

  log "Setup complete!"
  log "After reboot, ads should be blocked system-wide"
  log "You can manage hosts in the AdAway app or by updating the module"
}

main "$@"