platform/src/servers/api/chat/list-models.ts

import type { ModelInfo } from './types';
import { OPENCODE_SERVER_URL } from './opencode/server-manager';

// The Claude harness runs the `claude` CLI, so its tiers are a fixed set.
const CLAUDE_CODE_MODELS: ModelInfo[] = [
  { id: 'claude-code/opus', name: 'opus', provider: 'claude-code', contextWindow: 200000, maxTokens: 16000, reasoning: true, images: true },
  { id: 'claude-code/sonnet', name: 'sonnet', provider: 'claude-code', contextWindow: 200000, maxTokens: 16000, reasoning: true, images: true },
  { id: 'claude-code/haiku', name: 'haiku', provider: 'claude-code', contextWindow: 200000, maxTokens: 8192, reasoning: false, images: true },
];

// Cache the OpenCode catalog; it's stable for a session.
let openCodeCache: ModelInfo[] | null = null;

export function invalidateModelCache(): void {
  openCodeCache = null;
}

type ProvidersResponse = {
  providers?: Array<{ id?: string; models?: Record<string, unknown> }>;
};

// Enumerate OpenCode models from the fixed server's GET /config/providers (reliable — no subprocess).
// Model ids are `providerID/modelID` (e.g. `opencode/claude-haiku-4-5`); metadata is left at neutral
// defaults for now.
async function listOpenCodeModels(): Promise<ModelInfo[]> {
  if (openCodeCache) return openCodeCache;
  try {
    const res = await fetch(`${OPENCODE_SERVER_URL}/config/providers`, { signal: AbortSignal.timeout(5000) });
    if (!res.ok) return [];
    const data = (await res.json()) as ProvidersResponse;

    const models: ModelInfo[] = [];
    for (const provider of data.providers ?? []) {
      const providerId = provider.id ?? '';
      for (const modelId of Object.keys(provider.models ?? {})) {
        models.push({
          id: `${providerId}/${modelId}`,
          name: modelId,
          provider: providerId,
          contextWindow: 200000,
          maxTokens: 8192,
          reasoning: false,
          images: true,
        });
      }
    }

    openCodeCache = models;
    return models;
  } catch {
    return [];
  }
}

export async function listChatModels(): Promise<ModelInfo[]> {
  const openCode = await listOpenCodeModels();
  return [...CLAUDE_CODE_MODELS, ...openCode];
}