import type { OpencodeSession } from '@/types/opencode';

function record(value: unknown): Record<string, unknown> | null {
  return value !== null && typeof value === 'object'
    ? value as Record<string, unknown>
    : null;
}

function timestamp(value: unknown): number | null {
  if (typeof value === 'number' && Number.isFinite(value)) return value;
  if (typeof value !== 'string') return null;
  const parsed = Date.parse(value);
  return Number.isFinite(parsed) ? parsed : null;
}

function hasPositiveNumber(value: unknown): boolean {
  if (typeof value === 'number') return Number.isFinite(value) && value > 0;
  const item = record(value);
  return item ? Object.values(item).some(hasPositiveNumber) : false;
}

function hasMeaningfulSummary(value: unknown): boolean {
  if (typeof value === 'string') return value.trim().length > 0;
  if (typeof value === 'number') return Number.isFinite(value) && value > 0;
  if (typeof value === 'boolean') return value;
  if (Array.isArray(value)) return value.length > 0;
  const item = record(value);
  return item ? Object.values(item).some(hasMeaningfulSummary) : false;
}

function hasConversationActivity(session: OpencodeSession): boolean {
  const time = record(session.time);
  const created = timestamp(time?.created ?? session.createdAt);
  const updated = timestamp(time?.updated ?? session.updatedAt);
  return Boolean(created !== null && updated !== null && updated > created)
    || hasPositiveNumber(session.cost)
    || hasPositiveNumber(session.tokens)
    || hasMeaningfulSummary(session.summary);
}

export function findPrimaryProjectAgentSession(
  sessions: OpencodeSession[],
  agentId: string,
): OpencodeSession | undefined {
  const matches = sessions.filter((session) => session.agent === agentId);
  return matches.find(hasConversationActivity) ?? matches[0];
}