import type { GatewayTask } from '@easyai-ai-gateway/contracts';
import {
  createCompatibleChatCompletion,
  createEmbedding,
  createImageEditTask,
  createImageGenerationTask,
  createRerank,
  createResponse,
  createVideoGenerationTask,
  getAPITask,
} from '../api';
import type { TaskForm, TaskSubmissionMode } from '../types';

export interface RunTaskResponse {
  localOnly?: boolean;
  next?: Record<string, string>;
  submissionMode: TaskSubmissionMode;
  task: GatewayTask;
}

export interface RunTaskOptions {
  requestBody?: Record<string, unknown>;
  submissionMode?: TaskSubmissionMode;
}

const simulationParameterKeys = ['runMode', 'run_mode', 'simulation', 'testMode', 'test_mode'] as const;

export function applyTaskSubmissionMode(
  input: Record<string, unknown>,
  submissionMode: TaskSubmissionMode,
): Record<string, unknown> {
  const body = { ...input };
  for (const key of simulationParameterKeys) delete body[key];
  if (submissionMode === 'simulation') {
    body.runMode = 'simulation';
    body.simulation = true;
  }
  return body;
}

export async function runTask(token: string, task: TaskForm, options: RunTaskOptions = {}): Promise<RunTaskResponse> {
  const submissionMode = options.submissionMode ?? 'simulation';
  const requestBody = task.kind === 'tasks.retrieve'
    ? { taskId: task.taskId }
    : applyTaskSubmissionMode(options.requestBody ?? defaultRequestBody(task), submissionMode);

  if (task.kind === 'chat.completions') {
    const result = await createCompatibleChatCompletion(
      token,
      requestBody as Parameters<typeof createCompatibleChatCompletion>[1],
    );
    return { localOnly: true, submissionMode, task: compatibleTask(task, result, requestBody, submissionMode) };
  }
  if (task.kind === 'responses') {
    const result = await createResponse(token, requestBody as Parameters<typeof createResponse>[1]);
    return { localOnly: true, submissionMode, task: compatibleTask(task, result, requestBody, submissionMode) };
  }
  if (task.kind === 'embeddings') {
    const result = await createEmbedding(token, requestBody as Parameters<typeof createEmbedding>[1]);
    return { localOnly: true, submissionMode, task: compatibleTask(task, result, requestBody, submissionMode) };
  }
  if (task.kind === 'reranks') {
    const result = await createRerank(token, requestBody as Parameters<typeof createRerank>[1]);
    return { localOnly: true, submissionMode, task: compatibleTask(task, result, requestBody, submissionMode) };
  }
  if (task.kind === 'images.generations') {
    const response = await createImageGenerationTask(
      token,
      requestBody as Parameters<typeof createImageGenerationTask>[1],
    );
    return { ...response, submissionMode };
  }
  if (task.kind === 'images.edits') {
    const response = await createImageEditTask(token, requestBody as Parameters<typeof createImageEditTask>[1]);
    return { ...response, submissionMode };
  }
  if (task.kind === 'videos.generations') {
    const response = await createVideoGenerationTask(
      token,
      requestBody as unknown as Parameters<typeof createVideoGenerationTask>[1],
    );
    return { ...response, submissionMode };
  }
  if (task.kind === 'tasks.retrieve') {
    const taskId = task.taskId?.trim();
    if (!taskId) throw new Error('请输入要取回的 Task ID');
    const result = await getAPITask(token, taskId);
    return {
      localOnly: true,
      submissionMode: 'production',
      task: compatibleTask(task, result as unknown as Record<string, unknown>, requestBody, 'production'),
    };
  }
  throw new Error(`Unsupported task kind: ${task.kind}`);
}

function compatibleTask(
  task: TaskForm,
  result: Record<string, unknown>,
  requestBody: Record<string, unknown>,
  submissionMode: TaskSubmissionMode,
): GatewayTask {
  const now = new Date().toISOString();
  return {
    id: `docs-${task.kind}-${Date.now()}`,
    asyncMode: false,
    createdAt: now,
    finishedAt: now,
    kind: task.kind,
    model: typeof requestBody.model === 'string' ? requestBody.model : task.model,
    modelType: modelTypeForKind(task.kind),
    request: requestBody,
    result,
    runMode: submissionMode,
    status: 'succeeded',
    updatedAt: now,
    userId: 'docs-runner',
  };
}

function defaultRequestBody(task: TaskForm): Record<string, unknown> {
  if (task.kind === 'chat.completions') {
    return {
      model: task.model,
      messages: [{ role: 'user', content: task.prompt }],
      stream: false,
    };
  }
  if (task.kind === 'responses') {
    return {
      model: task.model,
      input: task.prompt,
      instructions: task.instructions,
      previous_response_id: task.previousResponseId,
      store: true,
      stream: false,
    };
  }
  if (task.kind === 'embeddings') {
    return {
      model: task.model,
      input: embeddingInput(task.prompt),
      dimensions: task.dimensions,
    };
  }
  if (task.kind === 'reranks') {
    return {
      model: task.model,
      query: task.prompt,
      documents: rerankDocuments(task.documents),
      top_n: task.topN,
    };
  }
  if (task.kind === 'images.generations') {
    return {
      model: task.model,
      prompt: task.prompt,
      quality: 'medium',
      size: '1024x1024',
    };
  }
  if (task.kind === 'images.edits') {
    return {
      model: task.model,
      prompt: task.prompt,
      image: task.image,
      mask: task.mask,
    };
  }
  if (task.kind === 'videos.generations') {
    return {
      model: task.model,
      content: [{ type: 'text', text: task.prompt }],
      aspect_ratio: task.aspectRatio ?? '16:9',
      resolution: task.resolution ?? '720p',
      duration: task.duration ?? 5,
      audio: task.outputAudio ?? true,
    };
  }
  if (task.kind === 'tasks.retrieve') return { taskId: task.taskId };
  return { model: task.model };
}

function embeddingInput(prompt: string) {
  const lines = splitLines(prompt);
  return lines.length > 1 ? lines : (lines[0] ?? prompt);
}

function rerankDocuments(value?: string) {
  const documents = splitLines(value ?? '');
  return documents.length ? documents : ['AI Gateway 提供 OpenAI 兼容接口。', '图片生成任务支持异步队列。'];
}

function splitLines(value: string) {
  return value
    .split(/\n+/)
    .map((item) => item.trim())
    .filter(Boolean);
}

function modelTypeForKind(kind: TaskForm['kind']) {
  if (kind === 'embeddings') return 'text_embedding';
  if (kind === 'reranks') return 'text_rerank';
  if (kind === 'images.generations') return 'image_generate';
  if (kind === 'images.edits') return 'image_edit';
  if (kind === 'videos.generations') return 'video_generate';
  if (kind === 'tasks.retrieve') return 'task';
  return 'text_generate';
}