export interface SlackMessage {
  text?: string;
  blocks?: SlackBlock[];
  channel?: string;
}

interface SlackBlock {
  type: string;
  text?: { type: string; text: string };
  elements?: unknown[];
}

/**
 * Send a message to a Slack webhook URL.
 */
export async function sendSlackMessage(
  webhookUrl: string,
  message: SlackMessage
): Promise<void> {
  const res = await fetch(webhookUrl, {
    method: "POST",
    headers: { "Content-Type": "application/json" },
    body: JSON.stringify(message),
  });

  if (!res.ok) {
    const body = await res.text();
    console.error("[Slack] Webhook failed:", res.status, body);
  }
}

/**
 * Send a plain text Slack notification.
 */
export async function sendSlackText(
  webhookUrl: string,
  text: string
): Promise<void> {
  return sendSlackMessage(webhookUrl, { text });
}

// ── Pre-built notification templates ─────────────────────────────────────────

export async function slackNotifyVersionUploaded(
  webhookUrl: string,
  params: {
    shotCode: string;
    versionLabel: string;
    artistName: string;
    projectName: string;
    reviewUrl: string;
  }
) {
  await sendSlackMessage(webhookUrl, {
    blocks: [
      {
        type: "section",
        text: {
          type: "mrkdwn",
          text: `🎬 *New version uploaded*\n*${params.projectName}* · ${params.shotCode} ${params.versionLabel} by ${params.artistName}`,
        },
      },
      {
        type: "actions",
        elements: [
          {
            type: "button",
            text: { type: "plain_text", text: "Review Now" },
            url: params.reviewUrl,
            style: "primary",
          },
        ],
      },
    ],
  });
}

export async function slackNotifyApproval(
  webhookUrl: string,
  params: {
    shotCode: string;
    versionLabel: string;
    status: "APPROVED" | "REJECTED" | "NEEDS_CHANGES";
    reviewerName: string;
    projectName: string;
    reviewUrl: string;
  }
) {
  const icons = {
    APPROVED: "✅",
    REJECTED: "❌",
    NEEDS_CHANGES: "⚠️",
  };

  const labels = {
    APPROVED: "approved",
    REJECTED: "rejected",
    NEEDS_CHANGES: "needs changes",
  };

  const icon = icons[params.status];
  const label = labels[params.status];

  await sendSlackMessage(webhookUrl, {
    blocks: [
      {
        type: "section",
        text: {
          type: "mrkdwn",
          text: `${icon} *${params.shotCode} ${params.versionLabel} ${label}*\nBy ${params.reviewerName} · ${params.projectName}`,
        },
      },
      {
        type: "actions",
        elements: [
          {
            type: "button",
            text: { type: "plain_text", text: "View Version" },
            url: params.reviewUrl,
          },
        ],
      },
    ],
  });
}

export async function slackNotifyTaskReadyForReview(
  webhookUrl: string,
  params: {
    taskTitle: string;
    contextCode: string | null;
    artistName: string;
    projectName: string;
    taskUrl: string;
  }
) {
  const label = params.contextCode ? `${params.contextCode} — ` : "";
  await sendSlackMessage(webhookUrl, {
    blocks: [
      {
        type: "section",
        text: {
          type: "mrkdwn",
          text: `👁 *Task ready for review*\n*${params.projectName}* · ${label}${params.taskTitle}\nSubmitted by ${params.artistName}`,
        },
      },
      {
        type: "actions",
        elements: [
          {
            type: "button",
            text: { type: "plain_text", text: "Review Task" },
            url: params.taskUrl,
            style: "primary",
          },
        ],
      },
    ],
  });
}

export async function slackNotifyTaskAssigned(
  webhookUrl: string,
  params: {
    taskTitle: string;
    contextCode: string | null;
    artistName: string;
    assignedByName: string;
    projectName: string;
    taskUrl: string;
  }
) {
  const label = params.contextCode ? `${params.contextCode} — ` : "";
  await sendSlackMessage(webhookUrl, {
    blocks: [
      {
        type: "section",
        text: {
          type: "mrkdwn",
          text: `📋 *Task assigned*\n*${params.projectName}* · ${label}${params.taskTitle}\nAssigned to ${params.artistName} by ${params.assignedByName}`,
        },
      },
      {
        type: "actions",
        elements: [
          {
            type: "button",
            text: { type: "plain_text", text: "View Task" },
            url: params.taskUrl,
          },
        ],
      },
    ],
  });
}

export async function slackNotifyNewFeedback(
  webhookUrl: string,
  params: {
    shotCode: string;
    frameNumber: number;
    authorName: string;
    commentText: string;
    reviewUrl: string;
  }
) {
  const truncated =
    params.commentText.length > 120
      ? params.commentText.slice(0, 117) + "..."
      : params.commentText;

  await sendSlackMessage(webhookUrl, {
    blocks: [
      {
        type: "section",
        text: {
          type: "mrkdwn",
          text: `💬 *New feedback* on ${params.shotCode} frame ${params.frameNumber}\n*${params.authorName}:* ${truncated}`,
        },
      },
      {
        type: "actions",
        elements: [
          {
            type: "button",
            text: { type: "plain_text", text: "Jump to Frame" },
            url: params.reviewUrl,
          },
        ],
      },
    ],
  });
}