defmodule Mix.Tasks.Mob.Install do
  use Mix.Task

  @shortdoc "First-run setup for a new Mob project"

  @moduledoc """
  Runs first-time setup for a Mob project generated by `mix mob.new`.

  Must be run from inside the project directory (the one containing `mix.exs`).

      mix mob.install [--no-icon] [--icon PATH]

  ## What it does

    1. Generates app icons (random robot avatar, or a provided source image)

  ## Options

    * `--no-icon`      — skip icon generation
    * `--icon PATH`    — use an existing image instead of generating a random robot

  ## Icon output

    - `android/app/src/main/res/mipmap-*/ic_launcher.png`
    - `ios/Assets.xcassets/AppIcon.appiconset/icon_*.png` + `Contents.json`
    - `icon_source.png` (1024×1024 master, when generating)

  Run at any time to regenerate icons:

      mix mob.install --no-icon        # skip icons, re-run other setup steps
      mix mob.icon                     # icon only, any time after install
  """

  @switches [no_icon: :boolean, icon: :string]

  @impl Mix.Task
  def run(argv) do
    {opts, _args, _} = OptionParser.parse(argv, strict: @switches)

    project_dir = File.cwd!()

    unless File.exists?(Path.join(project_dir, "mix.exs")) do
      Mix.raise("No mix.exs found. Run mix mob.install from your project root.")
    end

    unless opts[:no_icon] do
      generate_icons(project_dir, opts[:icon])
    end

    Mix.shell().info("""

    Mob project ready!

        mix mob.deploy       # build APK + push BEAMs + launch on devices
        mix mob.watch        # auto-push changes while developing
        mix mob.connect      # connect IEx to running device nodes
    """)
  end

  defp generate_icons(project_dir, nil) do
    Mix.shell().info("Generating app icon (random robot)...")
    MobDev.IconGenerator.generate_random(project_dir)
    Mix.shell().info([:green, "* icons written", :reset])
  end

  defp generate_icons(project_dir, source) do
    unless File.exists?(source) do
      Mix.raise("Source file not found: #{source}")
    end
    Mix.shell().info("Generating app icon from #{source}...")
    MobDev.IconGenerator.generate_from_source(source, project_dir)
    Mix.shell().info([:green, "* icons written", :reset])
  end
end