# Covers ADR-001, ADR-002, ADR-009, ADR-010 (multi-turn runner, tool behavior, usage/tracing)
Mix.Task.run("app.start")

alias Codex.{Agent, AgentRunner, Handoff, RunConfig, Tools}
alias Codex.Events
alias Codex.FunctionTool
alias Codex.Items.AgentMessage

defmodule CodexExamples.LiveMultiTurnRunner do
  @moduledoc false

  @default_prompt """
  Summarize this repository in one or two sentences.
  """

  defmodule RepoFactTool do
    use FunctionTool,
      name: "repo_fact",
      description: "Returns a quick fact about the repo to seed your answer",
      parameters: %{topic: :string},
      handler: fn %{"topic" => topic}, _ctx ->
        {:ok, %{"fact" => "codex_sdk demo fact for #{topic}: live multi-turn runner"}}
      end
  end

  def main(argv) do
    {opts, args, _} =
      OptionParser.parse(argv,
        switches: [max_turns: :integer, stop_on_tool: :boolean],
        aliases: [m: :max_turns]
      )

    prompt = parse_prompt(args)

    Codex.Tools.reset!()
    {:ok, _handle} = Tools.register(RepoFactTool)

    {:ok, helper_agent} =
      Agent.new(%{
        name: "TightenHelper",
        instructions: "Rewrite the provided note as one tight sentence and return it directly."
      })

    handoff =
      Handoff.wrap(helper_agent,
        tool_name: "handoff_helper",
        tool_description: "Delegate a draft reply for condensation",
        input_schema: %{
          "type" => "object",
          "properties" => %{"note" => %{"type" => "string"}},
          "required" => ["note"]
        }
      )

    tool_behavior =
      if opts[:stop_on_tool],
        do: :stop_on_first_tool,
        else: %{stop_at_tool_names: ["handoff_helper"]}

    {:ok, agent} =
      Agent.new(%{
        name: "Planner",
        instructions:
          "You may use repo_fact if it is available before answering. Optionally use handoff_helper if the note needs to be condensed.",
        tools: ["repo_fact"],
        handoffs: [handoff],
        tool_use_behavior: tool_behavior,
        reset_tool_choice: true
      })

    {:ok, run_config} =
      RunConfig.new(%{
        max_turns: opts[:max_turns] || 3,
        workflow: "live-multi-turn",
        group: "examples",
        trace_id: "multi-#{System.unique_integer([:positive])}",
        trace_include_sensitive_data: false
      })

    {:ok, codex_opts} =
      Codex.Options.new(%{
        codex_path_override: fetch_codex_path!()
      })

    {:ok, thread} = Codex.start_thread(codex_opts)

    IO.puts("""
    Running multi-turn loop against live Codex CLI.
      Prompt: #{String.trim(prompt)}
      Tool behavior: #{inspect(tool_behavior)}
      Max turns: #{run_config.max_turns}
    """)

    case AgentRunner.run(thread, prompt, %{agent: agent, run_config: run_config}) do
      {:ok, result} ->
        summarize_events(result.events)
        IO.puts("Attempts used: #{result.attempts}")
        IO.puts("Usage: #{inspect(result.thread.usage || %{})}")
        IO.puts("Final response:\n#{render_response(result.final_response)}")

      {:error, {:max_turns_exceeded, limit, context}} ->
        IO.puts("Hit max_turns=#{limit}, continuation=#{inspect(context)}")

      {:error, reason} ->
        Mix.raise("Multi-turn run failed: #{inspect(reason)}")
    end
  end

  defp summarize_events(events) do
    tool_events =
      Enum.filter(
        events,
        &(match?(%Events.ToolCallRequested{}, &1) or match?(%Events.ToolCallCompleted{}, &1))
      )

    Enum.each(tool_events, fn
      %Events.ToolCallRequested{tool_name: name, call_id: id, requires_approval: req?} ->
        IO.puts("Tool requested: #{name} (call_id=#{id}, requires_approval=#{req?})")

      %Events.ToolCallCompleted{tool_name: name, call_id: id, output: output} ->
        IO.puts("Tool completed: #{name} (call_id=#{id}) output=#{inspect(output)}")
    end)

    if tool_events == [] do
      IO.puts("No tool calls observed; custom tools may be unavailable in exec mode.")
    end

    case Enum.find(events, &match?(%Events.TurnContinuation{}, &1)) do
      %Events.TurnContinuation{continuation_token: token, reason: reason} ->
        IO.puts("Continuation suggested (reason=#{reason || "none"}): #{token}")

      _ ->
        :ok
    end
  end

  defp render_response(%AgentMessage{text: text}), do: text
  defp render_response(%{"text" => text}), do: text
  defp render_response(nil), do: "<no response>"
  defp render_response(other), do: inspect(other)

  defp parse_prompt([]), do: String.trim(@default_prompt)
  defp parse_prompt(values), do: Enum.join(values, " ")

  defp fetch_codex_path! do
    System.get_env("CODEX_PATH") ||
      System.find_executable("codex") ||
      Mix.raise("""
      Unable to locate the `codex` CLI.
      Install the Codex CLI and ensure it is on your PATH or set CODEX_PATH.
      """)
  end
end

CodexExamples.LiveMultiTurnRunner.main(System.argv())