import type { FileNode } from "@codeboard/shared";

const APPROX_CHARS_PER_TOKEN = 4;

export function chunkCode(content: string, maxTokens: number): string[] {
  const maxChars = maxTokens * APPROX_CHARS_PER_TOKEN;
  if (content.length <= maxChars) return [content];

  const lines = content.split("\n");
  const chunks: string[] = [];
  let current: string[] = [];
  let currentLen = 0;

  for (const line of lines) {
    if (currentLen + line.length > maxChars && current.length > 0) {
      chunks.push(current.join("\n"));
      current = [];
      currentLen = 0;
    }
    current.push(line);
    currentLen += line.length + 1;
  }

  if (current.length > 0) {
    chunks.push(current.join("\n"));
  }

  return chunks;
}

export function extractSignatures(fileNode: FileNode): string {
  const parts: string[] = [];

  parts.push(`File: ${fileNode.path} (${fileNode.language})`);

  if (fileNode.imports.length > 0) {
    parts.push("Imports:");
    for (const imp of fileNode.imports) {
      parts.push(`  from "${imp.source}" import {${imp.specifiers.join(", ")}}`);
    }
  }

  if (fileNode.exports.length > 0) {
    parts.push("Exports:");
    for (const exp of fileNode.exports) {
      parts.push(`  ${exp.isDefault ? "default " : ""}${exp.name}`);
    }
  }

  for (const fn of fileNode.functions) {
    const params = fn.params.join(", ");
    const ret = fn.returnType ? `: ${fn.returnType}` : "";
    const doc = fn.docstring ? ` — ${fn.docstring.slice(0, 100)}` : "";
    parts.push(`function ${fn.name}(${params})${ret}${doc}`);
  }

  for (const cls of fileNode.classes) {
    parts.push(`class ${cls.name}`);
    for (const method of cls.methods) {
      parts.push(`  method ${method.name}(${method.params.join(", ")})`);
    }
    for (const prop of cls.properties) {
      parts.push(`  property ${prop.name}${prop.type ? `: ${prop.type}` : ""}`);
    }
  }

  return parts.join("\n");
}

export function estimateTokens(text: string): number {
  return Math.ceil(text.length / APPROX_CHARS_PER_TOKEN);
}