import type { ExtensionAPI } from '@earendil-works/pi-coding-agent';
import { loadConfig } from './src/config';
import { fetchModelEntries } from './src/fetcher';
import { createModelLoadCoordinator, type LoadAttemptResult } from './src/loader';
import { buildProviderConfig } from './src/provider';
import type { ProviderModelConfig } from './src/types';

/**
 * CLIProxyAPI Pi Provider 扩展（1.1）。
 *
 * 启动流程：
 * 1. 读取 env；缺失则不注册
 * 2. async factory 内 boot 预拉（默认 5s）；失败/空列表注册空壳
 * 3. session_start：若仍无模型，生命周期内最多自动补拉一次（默认 5s）
 * 4. /cliproxy-reload：手动刷新（默认 30s）；失败或空列表不覆盖已有非空目录
 */
export default async function (pi: ExtensionAPI) {
  const loaded = loadConfig();
  if (!loaded.ok) {
    console.error(`[CLIProxyAPI] ${loaded.error}`);
    return;
  }

  const { config } = loaded;
  const providerConfig = buildProviderConfig(config.baseUrl, config.apiKey);

  const coordinator = createModelLoadCoordinator((timeoutMs) =>
    fetchModelEntries(config.modelsUrl, config.apiKey, timeoutMs),
  );

  function registerModels(models: ProviderModelConfig[]) {
    pi.registerProvider('cliproxy', {
      ...providerConfig,
      models,
    });
  }

  function notifyWarning(
    ctx: { ui: { notify: (message: string, type?: string) => void } },
    result: LoadAttemptResult,
  ) {
    let message = result.message;
    if (result.ui === 'failed_empty' || result.ui === 'empty') {
      message = `${message}。可在代理就绪后执行 /cliproxy-reload`;
    }
    ctx.ui.notify(`[CLIProxyAPI] ${message}`, 'warning');
  }

  // Boot preload
  const boot = await coordinator.load({
    timeoutMs: config.bootTimeoutMs,
    reason: 'boot',
  });
  registerModels(boot.acceptedModels);

  if (boot.ui === 'failed_empty' || boot.ui === 'empty') {
    console.error(`[CLIProxyAPI] ${boot.message}`);
  }

  pi.on('session_start', async (_event, ctx) => {
    // TUI is ready: surface boot success once if we already have models.
    if (coordinator.hasNonEmptyCatalog()) {
      const n = coordinator.consumePendingSuccessNotify();
      if (n !== null) {
        ctx.ui.notify(`[CLIProxyAPI] 已加载 ${n} 个模型`, 'info');
      }
      return;
    }

    if (!coordinator.shouldSessionAutoRetry()) {
      return;
    }

    const result = await coordinator.load({
      timeoutMs: config.retryTimeoutMs,
      reason: 'session-retry',
    });

    if (result.shouldRegister) {
      registerModels(result.acceptedModels);
    }

    if (result.ui === 'loaded') {
      const n = coordinator.consumePendingSuccessNotify();
      if (n !== null) {
        ctx.ui.notify(`[CLIProxyAPI] 已加载 ${n} 个模型`, 'info');
      }
      return;
    }

    if (result.ui !== 'session_retry_skipped') {
      notifyWarning(ctx, result);
    }
  });

  pi.registerCommand('cliproxy-reload', {
    description: '重新从 CLIProxyAPI 拉取模型列表',
    handler: async (_args, ctx) => {
      const result = await coordinator.load({
        timeoutMs: config.reloadTimeoutMs,
        reason: 'manual-reload',
      });

      if (result.shouldRegister) {
        registerModels(result.acceptedModels);
      }

      if (result.ui === 'loaded') {
        coordinator.markSuccessNotified();
        ctx.ui.notify(
          `[CLIProxyAPI] 已加载 ${result.acceptedModels.length} 个模型`,
          'info',
        );
        return;
      }

      notifyWarning(ctx, result);
    },
  });
}