defmodule MicrowavepropWeb.SubmitLive.PreviewComponent do
  @moduledoc false
  use MicrowavepropWeb, :html

  alias Phoenix.LiveView.Rendered

  @doc false
  @spec csv_preview(map()) :: Rendered.t()
  def csv_preview(assigns) do
    assigns =
      assign(assigns,
        valid_count: length(assigns.preview.valid),
        invalid_count: length(assigns.preview.invalid),
        duplicate_count: length(assigns.preview.duplicates),
        refinement_count: length(assigns.preview.refinements || []),
        valid_sample: Enum.take(assigns.preview.valid, 20),
        refinement_sample: Enum.take(assigns.preview.refinements || [], 50)
      )

    ~H"""
    <div class="space-y-6">
      <div>
        <h2 class="text-xl font-bold mb-2">Review before submitting</h2>
        <p class="text-sm opacity-70">
          Processed {@preview.total_rows} {if @preview.total_rows == 1, do: "row", else: "rows"}.
          Nothing has been inserted yet — confirm below to import.
        </p>
      </div>

      <div class="grid grid-cols-2 lg:grid-cols-4 gap-3">
        <.summary_card
          tone="success"
          label="Valid"
          value={@valid_count}
          hint="Will be inserted"
        />
        <.summary_card
          tone="info"
          label="Refinements"
          value={@refinement_count}
          hint="Will update existing contacts"
        />
        <.summary_card
          tone="warning"
          label="Duplicates"
          value={@duplicate_count}
          hint="Match existing or earlier rows"
        />
        <.summary_card
          tone="error"
          label="Invalid"
          value={@invalid_count}
          hint="Skipped — see errors"
        />
      </div>

      <div :if={@invalid_count > 0}>
        <h3 class="font-semibold mb-2">Invalid rows ({@invalid_count})</h3>
        <div class="overflow-x-auto rounded-box border border-base-300">
          <table class="table table-sm">
            <thead>
              <tr>
                <th class="w-24">Row</th>
                <th>Errors</th>
              </tr>
            </thead>
            <tbody>
              <tr :for={row <- Enum.take(@preview.invalid, 100)}>
                <td class="font-mono">Row {row.row_num}</td>
                <td>
                  <div :for={msg <- row.messages}>{msg}</div>
                </td>
              </tr>
            </tbody>
          </table>
        </div>
        <p :if={@invalid_count > 100} class="text-xs opacity-60 mt-1">
          Showing first 100 of {@invalid_count} invalid rows.
        </p>
      </div>

      <div :if={@refinement_count > 0}>
        <h3 class="font-semibold mb-2">Refinements ({@refinement_count})</h3>
        <p class="text-xs opacity-60 mb-2">
          These rows match an existing contact but add more precise data.
          Confirming will update the existing contact in place.
        </p>
        <div class="overflow-x-auto rounded-box border border-base-300">
          <table class="table table-sm">
            <thead>
              <tr>
                <th class="w-20">Row</th>
                <th>Station 1</th>
                <th>Station 2</th>
                <th>Band</th>
                <th>Changes</th>
              </tr>
            </thead>
            <tbody>
              <tr :for={row <- @refinement_sample}>
                <td class="font-mono">Row {row.row_num}</td>
                <td>{row.attrs["station1"]} <span class="opacity-60">{row.attrs["grid1"]}</span></td>
                <td>{row.attrs["station2"]} <span class="opacity-60">{row.attrs["grid2"]}</span></td>
                <td class="tabular-nums">{row.attrs["band"]}</td>
                <td class="text-xs">
                  <div :for={{field, value} <- Enum.sort(Map.to_list(row.changes))}>
                    <span class="opacity-60">{field}:</span>
                    <code class="text-xs">{value}</code>
                  </div>
                </td>
              </tr>
            </tbody>
          </table>
        </div>
        <p :if={@refinement_count > length(@refinement_sample)} class="text-xs opacity-60 mt-1">
          Showing first {length(@refinement_sample)} of {@refinement_count} refinements.
        </p>
      </div>

      <div :if={@duplicate_count > 0}>
        <h3 class="font-semibold mb-2">Duplicates ({@duplicate_count})</h3>
        <p class="text-xs opacity-60 mb-2">
          Same two callsigns at the same grids on the same band within an hour.
        </p>
        <div class="overflow-x-auto rounded-box border border-base-300">
          <table class="table table-sm">
            <thead>
              <tr>
                <th class="w-20">Row</th>
                <th>Station 1</th>
                <th>Station 2</th>
                <th>Band</th>
                <th>Timestamp</th>
                <th>Source</th>
              </tr>
            </thead>
            <tbody>
              <tr :for={row <- Enum.take(@preview.duplicates, 100)}>
                <td class="font-mono">Row {row.row_num}</td>
                <td>{row.attrs["station1"]} <span class="opacity-60">{row.attrs["grid1"]}</span></td>
                <td>{row.attrs["station2"]} <span class="opacity-60">{row.attrs["grid2"]}</span></td>
                <td class="tabular-nums">{row.attrs["band"]}</td>
                <td class="font-mono text-xs">
                  {Calendar.strftime(row.timestamp, "%Y-%m-%d %H:%M UTC")}
                </td>
                <td class="text-xs opacity-70">{duplicate_source(row.reason)}</td>
              </tr>
            </tbody>
          </table>
        </div>
        <p :if={@duplicate_count > 100} class="text-xs opacity-60 mt-1">
          Showing first 100 of {@duplicate_count} duplicates.
        </p>
      </div>

      <div :if={@valid_count > 0}>
        <h3 class="font-semibold mb-2">Valid rows ready to import ({@valid_count})</h3>
        <div class="overflow-x-auto rounded-box border border-base-300">
          <table class="table table-sm">
            <thead>
              <tr>
                <th class="w-20">Row</th>
                <th>Station 1</th>
                <th>Station 2</th>
                <th>Band</th>
                <th>Mode</th>
                <th>Timestamp</th>
              </tr>
            </thead>
            <tbody>
              <tr :for={row <- @valid_sample}>
                <td class="font-mono">Row {row.row_num}</td>
                <td>{row.attrs["station1"]} <span class="opacity-60">{row.attrs["grid1"]}</span></td>
                <td>{row.attrs["station2"]} <span class="opacity-60">{row.attrs["grid2"]}</span></td>
                <td class="tabular-nums">{row.attrs["band"]}</td>
                <td>{row.attrs["mode"]}</td>
                <td class="font-mono text-xs">
                  {Calendar.strftime(row.timestamp, "%Y-%m-%d %H:%M UTC")}
                </td>
              </tr>
            </tbody>
          </table>
        </div>
        <p :if={@valid_count > length(@valid_sample)} class="text-xs opacity-60 mt-1">
          Showing first {length(@valid_sample)} of {@valid_count} valid rows.
        </p>
      </div>

      <div class="flex flex-wrap gap-2 pt-4 border-t border-base-300">
        <button
          :if={@valid_count > 0 or @refinement_count > 0}
          type="button"
          class="btn btn-primary btn-lg"
          phx-click="confirm_csv"
          phx-disable-with="Importing..."
          data-confirm={confirm_prompt(@valid_count, @refinement_count)}
        >
          <.icon name="hero-check" class="w-5 h-5" />
          {confirm_button_label(@valid_count, @refinement_count)}
        </button>
        <button type="button" class="btn btn-ghost" phx-click="cancel_csv">
          Cancel
        </button>
      </div>
    </div>
    """
  end

  attr :tone, :string, required: true
  attr :label, :string, required: true
  attr :value, :integer, required: true
  attr :hint, :string, required: true

  @doc false
  @spec summary_card(map()) :: Rendered.t()
  def summary_card(assigns) do
    ~H"""
    <div class={[
      "rounded-box border p-4",
      case @tone do
        "success" -> "border-success/30 bg-success/10"
        "warning" -> "border-warning/30 bg-warning/10"
        "error" -> "border-error/30 bg-error/10"
        "info" -> "border-info/30 bg-info/10"
        _ -> "border-base-300 bg-base-200"
      end
    ]}>
      <div class="text-xs uppercase tracking-wider opacity-70">{@label}</div>
      <div class="text-3xl font-bold tabular-nums">{@value}</div>
      <div class="text-xs opacity-60">{@hint}</div>
    </div>
    """
  end

  defp duplicate_source(:existing_contact), do: "Already in database"
  defp duplicate_source(:earlier_in_upload), do: "Earlier row in this upload"
  defp duplicate_source(_), do: "Duplicate"

  defp pluralize(1, word), do: word
  defp pluralize(_, word), do: word <> "s"

  defp confirm_button_label(valid, 0) do
    "Looks good — submit #{valid} #{pluralize(valid, "contact")}"
  end

  defp confirm_button_label(0, refined) do
    "Looks good — refine #{refined} existing #{pluralize(refined, "contact")}"
  end

  defp confirm_button_label(valid, refined) do
    "Looks good — submit #{valid} and refine #{refined}"
  end

  defp confirm_prompt(valid, 0), do: "Import #{valid} contacts?"
  defp confirm_prompt(0, refined), do: "Refine #{refined} existing contacts?"

  defp confirm_prompt(valid, refined) do
    "Import #{valid} contacts and refine #{refined} existing?"
  end
end