import OpenAI from "openai";

// the newest OpenAI model is "gpt-5" which was released August 7, 2025. do not change this unless explicitly requested by the user
const openai = new OpenAI({ apiKey: process.env.OPENAI_API_KEY });

export interface DescriptionGenerationOptions {
  maxCharacters?: number;
  language?: string;
  includeArtistInfo?: boolean;
  includeLabelInfo?: boolean;
}

export async function generateVideoDescription(
  title: string, 
  options: DescriptionGenerationOptions = {}
): Promise<string> {
  const {
    maxCharacters = 500,
    language = "slovenian",
    includeArtistInfo = true,
    includeLabelInfo = true
  } = options;

  try {
    const prompt = `Analiziraj naslov videoisranja: "${title}"

Nalogo izvršit v slovenskem jeziku.

Iz naslova izvleci:
- Ime izvajalca/umetnika
- Naslov skladbe/komada 
- Tip vsebine (pesem, instrumental, live nastop, itd.)

Ustvari informativen opis, ki vključuje:
${includeArtistInfo ? '- Informacije o izvajalcu (stil glasbe, kratka zgodovina, znani komadi)' : ''}
${includeLabelInfo ? '- Informacije o založbi ali labelu, če je znan' : ''}
- Opis stila glasbe in žanra
- Kratko ozadje o komadu, če je znan
- Čemu je namenjen (ples, poslušanje, koncert, itd.)

Opis naj bo dolg maksimalno ${maxCharacters} znakov.
Opis naj bo napisan v prijaznem, informativnem tonu.
Ne uporabljaj besed "video" ali "posnetek" - piši o glasbi sami.

Odgovori samo z opisom, brez dodatnih pojasnil.`;

    const response = await openai.chat.completions.create({
      model: "gpt-5", // the newest OpenAI model is "gpt-5" which was released August 7, 2025
      messages: [
        {
          role: "system",
          content: "Si strokovnjak za glasbo in pomagaš ustvarjati kakovostne opise za glasbene vsebine. Odgovarjaš vedno v slovenskem jeziku."
        },
        {
          role: "user", 
          content: prompt
        }
      ],
      max_completion_tokens: Math.ceil(maxCharacters / 2), // Rough estimate: 2 characters per token
    });

    const description = response.choices[0].message.content?.trim() || "";
    
    // Ensure we don't exceed character limit
    if (description.length > maxCharacters) {
      return description.substring(0, maxCharacters - 3) + "...";
    }
    
    return description;
    
  } catch (error) {
    console.error("Error generating video description:", error);
    throw new Error("Napaka pri generiranju opisa s strani AI");
  }
}

export async function generateBulkDescriptions(
  videos: Array<{ id: string; title: string }>,
  options: DescriptionGenerationOptions = {}
): Promise<Array<{ id: string; description: string; error?: string }>> {
  const results = [];
  
  for (const video of videos) {
    try {
      const description = await generateVideoDescription(video.title, options);
      results.push({ id: video.id, description });
      
      // Add small delay to respect API rate limits
      await new Promise(resolve => setTimeout(resolve, 100));
    } catch (error) {
      results.push({ 
        id: video.id, 
        description: "", 
        error: error instanceof Error ? error.message : "Unknown error"
      });
    }
  }
  
  return results;
}