import type { ProviderAccount, ProviderVendorInfo } from '@/lib/providers';
import type { ProductModelRef } from '@/types/coding-conversation';

export interface CodingModelOption {
  key: string;
  accountId: string;
  modelId: string;
  label: string;
}

export function codingModelKey(model: Pick<ProductModelRef, 'accountId' | 'modelId'>): string {
  return JSON.stringify([model.accountId, model.modelId]);
}

export function parseCodingModelKey(key: string): Pick<ProductModelRef, 'accountId' | 'modelId'> | null {
  try {
    const value = JSON.parse(key) as unknown;
    if (!Array.isArray(value) || value.length !== 2) return null;
    const [accountId, modelId] = value;
    if (typeof accountId !== 'string' || !accountId.trim()
      || typeof modelId !== 'string' || !modelId.trim()) return null;
    return { accountId: accountId.trim(), modelId: modelId.trim() };
  } catch {
    return null;
  }
}

export function buildCodingModelOptions(
  accounts: ProviderAccount[],
  vendors: ProviderVendorInfo[],
): CodingModelOption[] {
  const vendorNames = new Map(vendors.map((vendor) => [vendor.id, vendor.name]));
  const seen = new Set<string>();
  const options: CodingModelOption[] = [];
  for (const account of accounts) {
    if (!account.enabled) continue;
    const modelIds = [
      account.model,
      ...(account.fallbackModels ?? []),
      ...(account.metadata?.customModels ?? []),
    ];
    for (const value of modelIds) {
      const modelId = value?.trim();
      if (!modelId) continue;
      const key = codingModelKey({ accountId: account.id, modelId });
      if (seen.has(key)) continue;
      seen.add(key);
      const vendor = vendorNames.get(account.vendorId);
      options.push({
        key,
        accountId: account.id,
        modelId,
        label: `${account.label}${vendor && vendor !== account.label ? ` · ${vendor}` : ''} / ${modelId}`,
      });
    }
  }
  return options;
}