export interface AttachedFileMeta {
  fileName: string;
  mimeType: string;
  fileSize: number;
  preview: string | null;
  filePath?: string;
  source?: 'user-upload' | 'tool-result' | 'message-ref';
}

export interface ContentBlockSource {
  type: string;
  media_type?: string;
  data?: string;
  url?: string;
}

export interface ContentBlock {
  type: 'text' | 'image' | 'thinking' | 'tool_use' | 'tool_result' | 'toolCall' | 'toolResult';
  text?: string;
  thinking?: string;
  source?: ContentBlockSource;
  data?: string;
  mimeType?: string;
  id?: string;
  name?: string;
  input?: unknown;
  arguments?: unknown;
  content?: string | ContentBlock[];
}

export type RawMessageRole = 'user' | 'assistant' | 'system' | 'toolresult' | 'tool_result';

export interface RawMessage {
  role: RawMessageRole;
  content: string | ContentBlock[];
  timestamp?: number;
  id?: string;
  toolCallId?: string;
  toolName?: string;
  details?: unknown;
  isError?: boolean;
  question?: string[];
  toolCall?: Record<string, unknown> | null;
  _attachedFiles?: AttachedFileMeta[];
}

export interface ToolStatus {
  id?: string;
  toolCallId?: string;
  name: string;
  status: 'running' | 'completed' | 'error';
  durationMs?: number;
  summary?: string;
  updatedAt: number;
}

export interface ChatSession {
  key: string;
  label?: string;
  displayName?: string;
  thinkingLevel?: string;
  model?: string;
  updatedAt?: number;
}

export function extractText(message?: RawMessage | null): string {
  if (!message) return '';

  if (typeof message.content === 'string') {
    return message.content;
  }

  return message.content
    .filter((block) => block.type === 'text' && typeof block.text === 'string')
    .map((block) => block.text ?? '')
    .join('\n');
}

export function extractThinking(message?: RawMessage | null): string | null {
  if (!message || !Array.isArray(message.content)) return null;

  const thinkingBlock = message.content.find((block) => block.type === 'thinking');
  return thinkingBlock?.thinking ?? null;
}

export function extractImages(message?: RawMessage | null): Array<{ url?: string; data?: string; mimeType: string }> {
  if (!message || !Array.isArray(message.content)) return [];

  const images: Array<{ url?: string; data?: string; mimeType: string }> = [];

  for (const block of message.content) {
    if (block.type === 'image') {
      if (block.source?.type === 'base64' && block.source.data) {
        images.push({
          data: block.source.data,
          mimeType: block.source.media_type || 'image/jpeg',
        });
      } else if (block.source?.type === 'url' && block.source.url) {
        images.push({
          url: block.source.url,
          mimeType: block.source.media_type || 'image/jpeg',
        });
      } else if (block.data) {
        images.push({
          data: block.data,
          mimeType: block.mimeType || 'image/jpeg',
        });
      }
    }

    if ((block.type === 'tool_result' || block.type === 'toolResult') && Array.isArray(block.content)) {
      images.push(...extractImages({ role: 'toolresult', content: block.content }));
    }
  }

  return images;
}

export function extractToolUse(message?: RawMessage | null): Array<{ id?: string; name: string; input?: unknown }> {
  if (!message || !Array.isArray(message.content)) return [];

  return message.content
    .filter((block) => block.type === 'tool_use' || block.type === 'toolCall')
    .map((block) => ({
      id: block.id,
      name: block.name || block.id || 'tool',
      input: block.input ?? block.arguments,
    }));
}

export function formatTimestamp(ts?: number): string {
  if (!ts) return '';

  const ms = ts < 1e12 ? ts * 1000 : ts;
  return new Date(ms).toLocaleString();
}

export function isToolResultRole(role?: string): boolean {
  if (!role) return false;

  const normalized = role.toLowerCase();
  return normalized === 'toolresult' || normalized === 'tool_result';
}

export function isToolOnlyMessage(message?: RawMessage): boolean {
  if (!message) return false;
  if (isToolResultRole(message.role)) return true;
  if (!Array.isArray(message.content)) return false;

  const hasToolBlock = message.content.some((block) =>
    ['tool_use', 'tool_result', 'toolCall', 'toolResult'].includes(block.type),
  );
  const hasTextBlock = message.content.some((block) => block.type === 'text' && block.text?.trim());
  const hasImageBlock = message.content.some((block) => block.type === 'image');

  return hasToolBlock && !hasTextBlock && !hasImageBlock;
}

export function isInternalMessage(message: { role?: string; content?: unknown }): boolean {
  if (message.role === 'system') return true;

  if (message.role === 'assistant') {
    const text = typeof message.content === 'string'
      ? message.content
      : extractText(message as RawMessage);

    if (/^(HEARTBEAT_OK|NO_REPLY)\s*$/.test(text)) {
      return true;
    }
  }

  return false;
}