import type { ThreadData, LinearIssue } from "./types";

export interface Attachment {
  linearIssue: string;
}

export function autoAttach(
  threads: ThreadData[],
  issues: LinearIssue[],
  attachments: Record<string, Attachment>,
): ThreadData[] {
  const issueMap: Record<string, LinearIssue> = {};
  for (const i of issues) issueMap[i.identifier] = i;

  return threads.map((t) => {
    const out = { ...t };

    if (t.channel === "linear" && issueMap[t.threadId]) {
      const iss = issueMap[t.threadId];
      out.linearIssue = iss.identifier;
      out.linearTitle = iss.title;
      out.linearUrl = iss.url;
      return out;
    }

    const m = t.subject.match(/\b(MAN-\d+)\b/);
    if (m && issueMap[m[1]]) {
      const iss = issueMap[m[1]];
      out.linearIssue = iss.identifier;
      out.linearTitle = iss.title;
      out.linearUrl = iss.url;
      return out;
    }

    if (!out.linearIssue && attachments[t.threadId]) {
      const a = attachments[t.threadId];
      if (issueMap[a.linearIssue]) {
        const iss = issueMap[a.linearIssue];
        out.linearIssue = iss.identifier;
        out.linearTitle = iss.title;
        out.linearUrl = iss.url;
      }
    }

    return out;
  });
}