import type { ContentPart, UnifiedMessage } from "./types";

export function textOf(parts: ContentPart[] | undefined | null): string {
  if (!parts) return "";
  return parts
    .filter((p): p is Extract<ContentPart, { type: "text" }> => p.type === "text")
    .map((p) => p.text)
    .join("");
}

export function hasImages(messages: UnifiedMessage[]): boolean {
  return messages.some((m) => m.content.some((p) => p.type === "image"));
}
export function hasFiles(messages: UnifiedMessage[]): boolean {
  return messages.some((m) => m.content.some((p) => p.type === "file"));
}

export const IMAGE_MIME = new Set(["image/png", "image/jpeg", "image/webp", "image/gif"]);
export const TEXT_LIKE_MIME = new Set([
  "text/plain",
  "text/markdown",
  "text/csv",
  "application/json",
  "text/html",
  "text/xml",
  "application/xml",
  "text/x-python",
  "text/javascript",
  "application/javascript",
  "text/typescript",
  "application/typescript",
  "text/x-c",
  "text/x-java",
  "text/x-go",
  "text/x-rust",
  "text/x-sh",
  "application/x-yaml",
  "text/yaml",
]);

export function isTextLike(mime: string, name?: string): boolean {
  if (TEXT_LIKE_MIME.has(mime) || mime.startsWith("text/")) return true;
  if (name && /\.(md|txt|csv|json|ts|tsx|js|jsx|py|go|rs|java|kt|swift|rb|php|c|cc|cpp|h|hpp|cs|sh|zsh|yaml|yml|toml|ini|sql|html|css|scss|xml|r|jl|lua|m|scala|dart|tex)$/i.test(name)) return true;
  return false;
}

/** Fallback for providers that don't accept text files natively: inline the file content. */
export function inlineTextFile(name: string, base64: string): string {
  const text = Buffer.from(base64, "base64").toString("utf8");
  return `<file name="${name}">\n${text}\n</file>`;
}