defmodule Integrations.HttpDisplay do
  @moduledoc """
  HTTP endpoint monitor's dashboard panel — display only, no collection.

  Renders the same panel `raven_integration_http`'s bundled module does, but
  as a standalone display with its own configurable watch-list of monitor
  ids — proof-of-shape package for `#261` (see `code-name-raven`'s backlog,
  "Display as an Independent, Installable Role"): the "separately-published
  display, no bundled monitor to assume" case. Declares compatibility with
  `Integrations.HttpMonitor` via `compatible_monitors/0`, but will render for
  any watched monitor whose collected result matches the shape it expects
  (`:status_code`, `:latency_ms`, `:timing`, etc.) — the same params
  `raven_integration_http_monitor` produces.
  """

  use CodeNameRaven.Display, category: :web, size_hint: :full

  def display_timezone, do: "America/Chicago"

  @impl true
  def compatible_monitors, do: [Integrations.HttpMonitor]

  @impl true
  def render(assigns) do
    window_seconds = assigns.config.display_window_seconds
    cutoff         = DateTime.add(DateTime.utc_now(), -window_seconds, :second)
    sample_key     = Map.get(assigns.config, :target_id) || assigns.config.id
    samples        = CodeNameRaven.Runtime.recent_samples(sample_key, limit: 120)
    samples        = Enum.filter(samples, fn s -> DateTime.compare(s.collected_at, cutoff) != :lt end)
    local_id       = CodeNameRaven.Runtime.instance_id()
    latest_local   = samples |> Enum.filter(&(&1.instance_id == local_id)) |> List.last()

    result =
      assigns[:result] || (latest_local && %{
        status_code:      latest_local.status_code,
        latency_ms:       latest_local.latency_ms,
        cert_expiry_days: latest_local.metrics["cert_expiry_days"],
        timing: %{
          dns_ms:      latest_local.metrics["dns_ms"],
          tcp_ms:      latest_local.metrics["tcp_ms"],
          ssl_ms:      latest_local.metrics["ssl_ms"],
          ttfb_ms:     latest_local.metrics["ttfb_ms"],
          download_ms: latest_local.metrics["download_ms"]
        },
        redirects:        latest_local.metrics["redirects"]
      })

    assigns = Map.merge(assigns, %{samples: samples, local_id: local_id, result: result})

    ~H"""
    <div class="space-y-4">
      <%!-- Header --%>
      <div class="flex items-start justify-between gap-2">
        <div class="min-w-0">
          <h2 class="text-sm font-semibold text-base-content truncate">
            <%= @config.name || @config.params[:url] || "HTTP Check" %>
          </h2>
          <p class="text-xs text-base-content/40 font-mono truncate">
            <%= @config.params[:url] %>
          </p>
        </div>
        <.status_chip status={@status} />
      </div>

      <%!-- Vital row --%>
      <div :if={@result} class="flex gap-4">
        <.stat label="Status" value={to_string(@result.status_code)} />
        <.stat label="Latency" value={"#{@result.latency_ms} ms"} />
        <div :if={Map.get(@result, :cert_expiry_days)} class="bg-base-200 rounded-lg px-3 py-2 flex-1 text-center">
          <p class="text-xs text-base-content/40">Cert Expiry</p>
          <p class="text-sm font-mono font-semibold text-success"><%= @result.cert_expiry_days %>d</p>
        </div>
        <div :if={Map.get(@result, :redirects) && @result.redirects > 0} class="bg-base-200 rounded-lg px-3 py-2 flex-1 text-center">
          <p class="text-xs text-base-content/40">Redirects</p>
          <p class="text-sm font-mono font-semibold text-base-content"><%= @result.redirects %></p>
        </div>
      </div>

      <%!-- Timing Breakdown --%>
      <div :if={@result && @result[:timing] && @result.timing.dns_ms} class="grid grid-cols-5 gap-2 bg-base-200/50 rounded-lg p-2.5 text-center text-xs">
        <div>
          <span class="text-base-content/40 block">DNS</span>
          <span class="font-mono font-semibold"><%= @result.timing.dns_ms %>ms</span>
        </div>
        <div>
          <span class="text-base-content/40 block">TCP</span>
          <span class="font-mono font-semibold"><%= @result.timing.tcp_ms %>ms</span>
        </div>
        <div>
          <span class="text-base-content/40 block">SSL</span>
          <span class="font-mono font-semibold"><%= if @result.timing.ssl_ms, do: "#{@result.timing.ssl_ms}ms", else: "—" %></span>
        </div>
        <div>
          <span class="text-base-content/40 block">TTFB</span>
          <span class="font-mono font-semibold"><%= @result.timing.ttfb_ms %>ms</span>
        </div>
        <div>
          <span class="text-base-content/40 block">Download</span>
          <span class="font-mono font-semibold"><%= @result.timing.download_ms %>ms</span>
        </div>
      </div>

      <%!-- Assertions Check --%>
      <div :if={@result && Map.has_key?(@result, :assertions) && @result.assertions != []} class="space-y-1">
        <h3 class="text-xs font-semibold text-base-content/60">Assertions Check</h3>
        <div class="space-y-1">
          <%= for assertion <- @result.assertions do %>
            <% outcome = CodeNameRaven.Monitor.Assertion.evaluate(assertion, @result) %>
            <div class="flex items-center justify-between text-xs p-1.5 rounded bg-base-200/20">
              <span class="font-mono truncate max-w-[80%] text-base-content/70">
                <%= assertion.type %><%= if assertion.target, do: " [#{assertion.target}]" %> <%= assertion.operator %> <%= inspect(assertion.value) %>
              </span>
              <%= if outcome == :pass do %>
                <span class="text-success font-semibold flex items-center gap-1">✓ Pass</span>
              <% else %>
                <span class="text-error font-semibold flex items-center gap-1">✗ Fail</span>
              <% end %>
            </div>
          <% end %>
        </div>
      </div>

      <%!-- Error --%>
      <p :if={@last_error} class="text-xs text-error font-mono truncate">
        <%= @last_error %>
      </p>

      <CodeNameRaven.MonitorComponents.line_chart
        id={"chart-#{@config.id}"}
        samples={@samples}
        local_id={@local_id}
      />

      <%!-- Footer --%>
      <p class="text-xs text-base-content/30">
        Checked <%= CodeNameRaven.Timezone.format_datetime(@last_checked_at, __MODULE__) %>
      </p>
    </div>
    """
  end

  # ---------------------------------------------------------------------------
  # Private components
  # ---------------------------------------------------------------------------

  defp status_chip(%{status: :up} = assigns) do
    ~H"""
    <span class="badge badge-success gap-1 px-3 py-3 text-xs font-semibold shrink-0">
      <span class="w-1.5 h-1.5 rounded-full bg-current"></span> Up
    </span>
    """
  end

  defp status_chip(%{status: :degraded} = assigns) do
    ~H"""
    <span class="badge badge-warning gap-1 px-3 py-3 text-xs font-semibold shrink-0">
      <span class="w-1.5 h-1.5 rounded-full bg-current"></span> Degraded
    </span>
    """
  end

  defp status_chip(%{status: :down} = assigns) do
    ~H"""
    <span class="badge badge-error gap-1 px-3 py-3 text-xs font-semibold shrink-0">
      <span class="w-1.5 h-1.5 rounded-full bg-current"></span> Down
    </span>
    """
  end

  defp status_chip(assigns) do
    ~H"""
    <span class="badge badge-neutral gap-1 px-3 py-3 text-xs font-semibold shrink-0">
      <span class="w-1.5 h-1.5 rounded-full bg-current"></span> Unknown
    </span>
    """
  end

  defp stat(assigns) do
    ~H"""
    <div class="bg-base-200 rounded-lg px-3 py-2 flex-1 text-center">
      <p class="text-xs text-base-content/40"><%= @label %></p>
      <p class="text-sm font-mono font-semibold text-base-content"><%= @value %></p>
    </div>
    """
  end
end