defmodule Mix.Tasks.Raxol.ErrorReport do
  @moduledoc """
  Generate comprehensive error reports using Phase 4.3 Error Experience system.

  ## Usage

  Generate a session report:
      mix raxol.error_report --session
      
  Generate a report for queued errors:
      mix raxol.error_report --process-queue
      
  Export reports in different formats:
      mix raxol.error_report --export --format json
      
  Get reporting statistics:
      mix raxol.error_report --stats
      
  Configure reporting:
      mix raxol.error_report --config level=comprehensive format=markdown
      
  ## Options

    * `--session` - Generate a comprehensive session report
    * `--process-queue` - Process queued errors and generate batch report
    * `--export` - Export existing reports
    * `--stats` - Show reporting statistics and configuration
    * `--config` - Update reporter configuration
    * `--format FORMAT` - Report format (text, json, markdown, html)
    * `--level LEVEL` - Report detail level (minimal, standard, comprehensive) 
    * `--output PATH` - Output file path for reports
    * `--no-persist` - Don't save reports to disk automatically
    * `--include-performance` - Include Phase 3 performance analysis
    * `--include-patterns` - Include error pattern learning data
    * `--include-suggestions` - Include fix suggestions
    
  ## Examples

      # Generate comprehensive session report in markdown
      mix raxol.error_report --session --level comprehensive --format markdown
      
      # Process error queue with minimal output
      mix raxol.error_report --process-queue --level minimal --format json
      
      # Update configuration for future reports
      mix raxol.error_report --config level=standard format=markdown auto_persist=true
      
      # Export reports for sharing
      mix raxol.error_report --export --format json --output error_summary.json
  """

  use Mix.Task
  alias Raxol.Core.ErrorReporter

  @impl Mix.Task
  def run(args) do
    Application.ensure_all_started(:raxol)

    {options, [], []} =
      OptionParser.parse(args,
        strict: [
          session: :boolean,
          process_queue: :boolean,
          export: :boolean,
          stats: :boolean,
          config: :string,
          format: :string,
          level: :string,
          output: :string,
          no_persist: :boolean,
          include_performance: :boolean,
          include_patterns: :boolean,
          include_suggestions: :boolean,
          help: :boolean
        ]
      )

    cond do
      options[:help] ->
        print_help()

      options[:stats] ->
        show_stats()

      options[:config] ->
        update_config(options)

      options[:session] ->
        generate_session_report(options)

      options[:process_queue] ->
        process_error_queue(options)

      options[:export] ->
        export_reports(options)

      true ->
        Mix.shell().info("Use --help to see available options")
        show_stats()
    end
  end

  defp print_help do
    Mix.shell().info(@moduledoc)
  end

  defp show_stats do
    case ErrorReporter.get_stats() do
      stats ->
        Mix.shell().info("""

        #{IO.ANSI.cyan()}Raxol Error Reporter Statistics#{IO.ANSI.reset()}
        #{String.duplicate("=", 35)}

        Session ID: #{stats.session_id}
        Errors Processed: #{stats.error_count}
        Queued Errors: #{stats.queued_errors}
        Last Report: #{format_datetime(stats.last_report_time)}

        #{IO.ANSI.green()}Configuration:#{IO.ANSI.reset()}
        - Level: #{stats.config.level}
        - Format: #{stats.config.format}
        - Auto Persist: #{stats.config.auto_persist}
        - Include Performance: #{stats.config.include_performance}
        - Include Patterns: #{stats.config.include_patterns}
        - Include Suggestions: #{stats.config.include_suggestions}

        Reports Directory: #{stats.reports_directory}
        """)
    end
  rescue
    error ->
      Mix.shell().error("Failed to get statistics: #{inspect(error)}")
  end

  defp update_config(options) do
    config_string = options[:config]

    try do
      config_updates = parse_config_string(config_string)

      case ErrorReporter.update_config(config_updates) do
        {:ok, new_config} ->
          Mix.shell().info(
            "#{IO.ANSI.green()}Configuration updated successfully!#{IO.ANSI.reset()}"
          )

          Mix.shell().info(
            "New configuration: #{inspect(new_config, pretty: true)}"
          )

        {:error, reason} ->
          Mix.shell().error(
            "Failed to update configuration: #{inspect(reason)}"
          )
      end
    catch
      :error, reason ->
        Mix.shell().error("Invalid configuration format: #{inspect(reason)}")

        Mix.shell().info(
          "Example: --config level=comprehensive,format=markdown,auto_persist=true"
        )
    end
  end

  defp generate_session_report(options) do
    report_opts = build_report_options(options)

    Mix.shell().info(
      "#{IO.ANSI.cyan()}Generating session report...#{IO.ANSI.reset()}"
    )

    case ErrorReporter.generate_session_report(report_opts) do
      {:ok, report} ->
        handle_report_output(report, options, "session_report")

        Mix.shell().info(
          "#{IO.ANSI.green()}Session report generated successfully!#{IO.ANSI.reset()}"
        )

      {:error, reason} ->
        Mix.shell().error(
          "Failed to generate session report: #{inspect(reason)}"
        )
    end
  end

  defp process_error_queue(options) do
    report_opts = build_report_options(options)

    Mix.shell().info(
      "#{IO.ANSI.cyan()}Processing error queue...#{IO.ANSI.reset()}"
    )

    case ErrorReporter.process_queue(report_opts) do
      {:ok, report}
      when is_binary(report) and report != "No queued errors to process" ->
        handle_report_output(report, options, "batch_report")

        Mix.shell().info(
          "#{IO.ANSI.green()}Batch report generated successfully!#{IO.ANSI.reset()}"
        )

      {:ok, message} ->
        Mix.shell().info("#{IO.ANSI.yellow()}#{message}#{IO.ANSI.reset()}")

      {:error, reason} ->
        Mix.shell().error("Failed to process queue: #{inspect(reason)}")
    end
  end

  defp export_reports(options) do
    export_opts = %{
      format: options[:format] || "json",
      output_path: options[:output],
      include_all: true
    }

    Mix.shell().info("#{IO.ANSI.cyan()}Exporting reports...#{IO.ANSI.reset()}")

    case ErrorReporter.export_reports(export_opts) do
      {:ok, result} ->
        Mix.shell().info(
          "#{IO.ANSI.green()}Reports exported successfully!#{IO.ANSI.reset()}"
        )

        Mix.shell().info("Export result: #{inspect(result, pretty: true)}")

      {:error, reason} ->
        Mix.shell().error("Failed to export reports: #{inspect(reason)}")
    end
  end

  defp build_report_options(options) do
    base_options = []

    base_options
    |> add_option_if_present(:level, options[:level])
    |> add_option_if_present(:format, options[:format])
    |> add_option_if_present(:auto_persist, not options[:no_persist])
    |> add_option_if_present(
      :include_performance,
      options[:include_performance]
    )
    |> add_option_if_present(:include_patterns, options[:include_patterns])
    |> add_option_if_present(
      :include_suggestions,
      options[:include_suggestions]
    )
    |> Enum.into(%{})
  end

  defp add_option_if_present(options, _key, nil), do: options

  defp add_option_if_present(options, key, value),
    do: [{key, parse_option_value(value)} | options]

  defp parse_option_value("true"), do: true
  defp parse_option_value("false"), do: false
  defp parse_option_value("minimal"), do: :minimal
  defp parse_option_value("standard"), do: :standard
  defp parse_option_value("comprehensive"), do: :comprehensive
  defp parse_option_value("text"), do: :text
  defp parse_option_value("json"), do: :json
  defp parse_option_value("markdown"), do: :markdown
  defp parse_option_value("html"), do: :html
  defp parse_option_value(value), do: value

  defp parse_config_string(config_string) do
    config_string
    |> String.split(",")
    |> Enum.map(&String.split(&1, "=", parts: 2))
    |> Enum.map(fn [key, value] ->
      {String.to_atom(String.trim(key)), parse_option_value(String.trim(value))}
    end)
    |> Enum.into(%{})
  end

  defp handle_report_output(report, options, report_type) do
    if output_path = options[:output] do
      File.write!(output_path, report)
      Mix.shell().info("Report written to: #{output_path}")
    else
      # Print to stdout if no output file specified
      Mix.shell().info(
        "\n#{IO.ANSI.bright()}#{String.upcase(report_type)}#{IO.ANSI.reset()}"
      )

      Mix.shell().info(String.duplicate("=", String.length(report_type) + 10))
      Mix.shell().info(report)
    end
  end

  defp format_datetime(nil), do: "Never"

  defp format_datetime(datetime) do
    Calendar.strftime(datetime, "%Y-%m-%d %H:%M:%S UTC")
  end
end