import type {
  SoraGenerationParams,
  SoraGenerationResult,
  SoraJob,
  NarrativeGenerationParams,
  NarrativeGenerationResult,
  StoryChoice
} from '$lib/types';

const API_BASE = 'https://api.openai.com/v1';

/**
 * Create a Sora video generation job
 */
export async function createSoraVideo(
  apiKey: string,
  params: SoraGenerationParams
): Promise<SoraJob> {
  const formData = new FormData();
  formData.append('model', params.model || 'sora-2');
  formData.append('prompt', params.prompt);
  formData.append('seconds', String(params.seconds || 8));

  if (params.size) {
    formData.append('size', params.size);
  }

  if (params.inputReference) {
    formData.append('input_reference', params.inputReference, 'reference.jpg');
  }

  const response = await fetch(`${API_BASE}/videos`, {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${apiKey}`
    },
    body: formData
  });

  if (!response.ok) {
    const error = await response.json().catch(() => ({ error: { message: response.statusText } }));
    throw new Error(`Failed to create video: ${error.error?.message || response.statusText}`);
  }

  return await response.json();
}

/**
 * Poll a Sora video job until completion
 */
export async function pollSoraJob(
  apiKey: string,
  jobId: string,
  onProgress?: (progress: number) => void
): Promise<SoraJob> {
  const POLL_INTERVAL = 2000; // 2 seconds
  const MAX_ATTEMPTS = 300; // 10 minutes max

  for (let attempt = 0; attempt < MAX_ATTEMPTS; attempt++) {
    const response = await fetch(`${API_BASE}/videos/${jobId}`, {
      headers: {
        'Authorization': `Bearer ${apiKey}`
      }
    });

    if (!response.ok) {
      throw new Error(`Failed to poll job: ${response.statusText}`);
    }

    const job: SoraJob = await response.json();

    if (onProgress && job.progress !== undefined) {
      onProgress(job.progress);
    }

    if (job.status === 'completed') {
      return job;
    }

    if (job.status === 'failed') {
      throw new Error(job.error?.message || 'Video generation failed');
    }

    await new Promise(resolve => setTimeout(resolve, POLL_INTERVAL));
  }

  throw new Error('Video generation timed out');
}

/**
 * Download the generated video content
 */
export async function downloadSoraVideo(
  apiKey: string,
  jobId: string
): Promise<string> {
  const response = await fetch(`${API_BASE}/videos/${jobId}/content?variant=video`, {
    headers: {
      'Authorization': `Bearer ${apiKey}`
    }
  });

  if (!response.ok) {
    throw new Error(`Failed to download video: ${response.statusText}`);
  }

  // Create a blob URL for the video
  const blob = await response.blob();
  return URL.createObjectURL(blob);
}

/**
 * Complete Sora video generation workflow
 */
export async function generateSoraVideo(
  apiKey: string,
  params: SoraGenerationParams,
  onProgress?: (progress: number) => void
): Promise<SoraGenerationResult> {
  // Create the job
  const job = await createSoraVideo(apiKey, params);

  // Poll until complete
  const completedJob = await pollSoraJob(apiKey, job.id, onProgress);

  // Download the video
  const videoUrl = await downloadSoraVideo(apiKey, completedJob.id);

  return {
    videoUrl,
    jobId: job.id
  };
}

/**
 * Generate narrative and choices using GPT-4
 */
export async function generateNarrative(
  apiKey: string,
  params: NarrativeGenerationParams
): Promise<NarrativeGenerationResult> {
  const systemPrompt = `You are a creative storyteller for an interactive video-based choose-your-own-adventure game.

Your role:
1. Write engaging first-person narrative text that describes what the protagonist sees and experiences
2. Create a detailed scene description optimized for Sora video generation (cinematic, specific about visuals, camera movement, lighting)
3. Generate 2-4 meaningful choices that continue the story in interesting directions

Guidelines:
- Keep narratives concise but immersive (2-4 sentences)
- Scene descriptions should be cinematic and specific about visual details
- Choices should be distinct and lead to different narrative paths
- Maintain story coherence and continuity
- Keep content appropriate for general audiences

Return a JSON object with this structure:
{
  "narrative": "First-person narrative text shown to the player",
  "sceneDescription": "Detailed visual description for Sora video generation",
  "choices": [
    {"id": "choice1", "text": "Action the player can take"},
    {"id": "choice2", "text": "Another action the player can take"},
    ...
  ]
}`;

  let userPrompt = '';

  if (params.isFirstScene) {
    userPrompt = `Create the opening scene for a new adventure. The player should start in an intriguing situation with clear choices ahead.`;
  } else {
    userPrompt = `Story context so far:\n${params.storyContext}\n\n`;
    if (params.userChoice) {
      userPrompt += `The player chose: ${params.userChoice}\n\n`;
    }
    userPrompt += `Continue the story from this point. What happens next?`;
  }

  const response = await fetch(`${API_BASE}/chat/completions`, {
    method: 'POST',
    headers: {
      'Authorization': `Bearer ${apiKey}`,
      'Content-Type': 'application/json'
    },
    body: JSON.stringify({
      model: 'gpt-4o',
      messages: [
        { role: 'system', content: systemPrompt },
        { role: 'user', content: userPrompt }
      ],
      response_format: { type: 'json_object' },
      temperature: 0.8
    })
  });

  if (!response.ok) {
    const error = await response.json().catch(() => ({ error: { message: response.statusText } }));
    throw new Error(`Failed to generate narrative: ${error.error?.message || response.statusText}`);
  }

  const data = await response.json();
  const content = data.choices[0]?.message?.content;

  if (!content) {
    throw new Error('No narrative generated');
  }

  const result = JSON.parse(content);

  // Validate and ensure IDs for choices
  const choices: StoryChoice[] = (result.choices || []).map((choice: any, index: number) => ({
    id: choice.id || `choice-${Date.now()}-${index}`,
    text: choice.text,
    description: choice.description
  }));

  return {
    narrative: result.narrative || '',
    sceneDescription: result.sceneDescription || result.narrative,
    choices
  };
}

/**
 * Build a contextual prompt for Sora that includes continuity hints
 */
export function buildSoraPrompt(sceneDescription: string, storyContext?: string): string {
  if (!storyContext) {
    return sceneDescription;
  }

  // Add context similarly to sora-extend approach
  return `Context (for continuity):
${storyContext}

Scene:
${sceneDescription}

The scene should continue smoothly from the previous moment, maintaining consistent visual style, lighting, and subject identity.`;
}