import type { ImageAnnotationBounds } from "@/lib/api";

export type ImageEditAnnotation = {
  id: string;
  label: string;
  instruction: string;
  bounds: ImageAnnotationBounds;
  selectionType?: "box" | "point";
  point?: { x: number; y: number };
  visibleText?: string;
  description?: string;
};

export type ImageEditorGenerationSettings = {
  count: number;
  model: string;
  quality?: string;
  resolution?: string;
  thirdPartyImageGroupId?: string;
};

export type ImageEditorAction = (
  | {
      type: "annotations";
      annotations: ImageEditAnnotation[];
      /** 被编辑图片自身的宽高比（整数格式，如 "2:3"），局部修改时输出应保持该比例 */
      imageRatio?: string;
    }
  | {
      type: "expand";
      aspectRatio: string;
      instruction?: string;
      systemPrompt: string;
      fillColor: string;
      referenceImageDataUrl: string;
      referenceImageWidth: number;
      referenceImageHeight: number;
      maskImageDataUrl: string;
    }
) & ImageEditorGenerationSettings;

function percent(value: number) {
  return `${Math.max(0, Math.min(100, value)).toFixed(1)}%`;
}

/** 把扩图参考画布的像素宽高整理成 `宽x高` 形式，尺寸非法时返回空字符串。 */
export function toExpansionReferenceSize(width?: number, height?: number) {
  const parsedWidth = Math.round(Number(width) || 0);
  const parsedHeight = Math.round(Number(height) || 0);
  if (parsedWidth <= 0 || parsedHeight <= 0) return "";
  return `${parsedWidth}x${parsedHeight}`;
}

export function buildImageAnnotationEditPrompt(annotations: ImageEditAnnotation[]) {
  const actionable = annotations.filter((item) => item.instruction.trim());
  const items = actionable.map((item, index) => {
    const centerX = item.bounds.x + item.bounds.width / 2;
    const centerY = item.bounds.y + item.bounds.height / 2;
    const pointX = item.point?.x ?? centerX;
    const pointY = item.point?.y ?? centerY;
    const details = item.selectionType === "point"
      ? [
          `${index + 1}. 点选目标：${item.label.trim() || "用户点选位置"}`,
          `   点选位置：(x: ${percent(pointX)}, y: ${percent(pointY)})`,
          `   识别参考范围：(x: ${percent(item.bounds.x)}, y: ${percent(item.bounds.y)}, w: ${percent(item.bounds.width)}, h: ${percent(item.bounds.height)})`,
        ]
      : [
          `${index + 1}. 框选目标：${item.label.trim() || "用户框选区域"}`,
          `   区域中心：(x: ${percent(centerX)}, y: ${percent(centerY)})`,
          `   区域范围：(x: ${percent(item.bounds.x)}, y: ${percent(item.bounds.y)}, w: ${percent(item.bounds.width)}, h: ${percent(item.bounds.height)})`,
        ];
    if (item.visibleText?.trim()) {
      details.push(`   当前可见文字：${item.visibleText.trim()}`);
    }
    if (item.description?.trim()) {
      details.push(`   视觉说明：${item.description.trim()}`);
    }
    details.push(`   修改：${item.instruction.trim()}`);
    return details.join("\n");
  });

  return [
    "请编辑图像1。坐标以原图左上角为 (0%, 0%)，右下角为 (100%, 100%)。",
    "以下每一项都对应用户在原图上明确点选或框选的目标：",
    "",
    items.join("\n\n"),
    "",
    "严格只修改以上点选目标或框选区域；未标记的商品、人物、文字、构图、颜色、光线和背景保持不变。",
    "不要在成品中保留编号、点位、选框、坐标或任何标注界面元素。",
  ].join("\n");
}

export const DEFAULT_IMAGE_EXPANSION_FILL_COLOR = "#ffb6d9";

const IMAGE_EXPANSION_COLOR_NAMES: Record<string, string> = {
  "#ffffff": "白色",
  "#000000": "黑色",
  "#808080": "灰色",
  "#ff0000": "红色",
  "#00ff00": "绿色",
  "#0000ff": "蓝色",
  [DEFAULT_IMAGE_EXPANSION_FILL_COLOR]: "粉色",
};

export function describeImageExpansionFillColor(fillColor: string) {
  const normalized = fillColor.trim().toLowerCase();
  return IMAGE_EXPANSION_COLOR_NAMES[normalized] || `颜色为 ${normalized.toUpperCase()} 的纯色`;
}

export function buildDefaultImageExpansionPrompt(fillColor = DEFAULT_IMAGE_EXPANSION_FILL_COLOR) {
  const colorDescription = describeImageExpansionFillColor(fillColor);
  return `第一张参考图是扩展画布，其中${colorDescription}色块是需要补全的新增区域。透明蒙版可能作为第二张参考图提供，也可能通过 mask 字段提供；蒙版的透明区域与这些色块对应，是唯一允许填充的区域，不透明区域必须保持不变。根据原图内容自然填充新增区域，保持原图的清晰程度、色调和颜色不变，新增区域和原图的衔接要自然`;
}

export const DEFAULT_IMAGE_EXPANSION_PROMPT = buildDefaultImageExpansionPrompt();

export function buildImageExpansionPrompt(
  systemPrompt: string,
  instruction?: string,
  fillColor = DEFAULT_IMAGE_EXPANSION_FILL_COLOR,
  aspectRatio?: string,
  referenceWidth?: number,
  referenceHeight?: number,
) {
  const normalizedSystemPrompt = systemPrompt.trim() || buildDefaultImageExpansionPrompt(fillColor);
  const extraInstruction = instruction?.trim();
  const parts = [normalizedSystemPrompt];
  const referenceSize = toExpansionReferenceSize(referenceWidth, referenceHeight);
  if (referenceSize) {
    // 用「参考画布的实际像素尺寸」约束比例，而不是 16:9 / 404:281 这类比例字符串：
    // 比例字符串会被后端换算成 1024 长边的标准尺寸，与扩图画布的真实宽高对不上，
    // 生成结果会被二次裁切，导致扩图内容错位。
    parts.push(
      `输出图片必须严格保持 ${referenceSize} 的像素尺寸与宽高比，不要拉伸、压缩或裁切画面，也不要改变画布比例。`,
    );
  } else if (aspectRatio?.trim()) {
    parts.push(`输出图片的宽高比必须为 ${aspectRatio.trim()}，请严格按照这个尺寸比例生成。`);
  }
  if (extraInstruction) {
    parts.push(`补充要求：${extraInstruction}`);
  }
  return parts.join("\n\n");
}