import { getLocaleInstruction } from './locale.js';

export type AnswerMode =
  | 'standard' | 'focus' | 'academic' | 'writing' | 'travel' | 'finance'
  | 'health' | 'education' | 'medicine' | 'realEstate' | 'psychology' | 'sports'
  | 'children' | 'goods' | 'shopping' | 'games' | 'taxes' | 'legislation';

export type ResponsePrefs = { format?: string; length?: string; tone?: string };

const VERTICAL_BLOCKS: Partial<Record<AnswerMode, string>> = {
  travel: `### Answer Mode: Travel\nPrioritize: destinations, itineraries, hotels, transport, practical tips. Format: clear sections (Where to stay, What to see, Getting there).\n`,
  finance: `### Answer Mode: Finance\nPrioritize: market data, company analysis, financial metrics. Cite sources for numbers.\n`,
  health: `### Answer Mode: Health\nPrioritize: wellness, medicine, nutrition, fitness, mental health. Cite medical sources.\n`,
  education: `### Answer Mode: Education\nPrioritize: learning, courses, pedagogy, academic resources.\n`,
  medicine: `### Answer Mode: Medicine\nPrioritize: clinical info, treatments, diagnostics. Cite medical sources.\n`,
  academic: `### Answer Mode: Academic\nPrioritize: scholarly sources, citations, research-based answers.\n`,
  writing: `### Answer Mode: Writing\nPrioritize: clear structure, engaging prose, well-cited content.\n`,
};

export function getWriterPrompt(
  context: string,
  systemInstructions: string,
  mode: 'speed' | 'balanced' | 'quality',
  locale?: string,
  memoryContext?: string,
  answerMode?: AnswerMode,
  responsePrefs?: ResponsePrefs,
  learningMode?: boolean,
  detectedLanguage?: string,
  isArticleSummary?: boolean,
): string {
  const memoryBlock = memoryContext?.trim()
    ? `\n### User memory (personalization)\nUse these stored facts/preferences to personalize when relevant. Do NOT cite as source.\n${memoryContext}\n`
    : '';
  const verticalBlock = answerMode ? (VERTICAL_BLOCKS[answerMode] ?? '') : '';

  const prefs: string[] = [];
  if (responsePrefs?.format) {
    const f = responsePrefs.format;
    if (f === 'bullets') prefs.push('Format: use bullet points where appropriate.');
    else if (f === 'outline') prefs.push('Format: use clear headings and outline structure.');
    else prefs.push('Format: use paragraphs and flowing prose.');
  }
  if (responsePrefs?.length) {
    const l = responsePrefs.length;
    if (l === 'short') prefs.push('Length: keep response concise and brief.');
    else if (l === 'long') prefs.push('Length: provide comprehensive, detailed coverage.');
    else prefs.push('Length: medium depth, balanced.');
  }
  if (responsePrefs?.tone) {
    const t = responsePrefs.tone;
    if (t === 'professional') prefs.push('Tone: formal, professional.');
    else if (t === 'casual') prefs.push('Tone: friendly, conversational.');
    else if (t === 'concise') prefs.push('Tone: direct, to the point.');
    else prefs.push('Tone: neutral.');
  }
  const prefsBlock = prefs.length ? `\n### Response preferences\n${prefs.join(' ')}\n` : '';

  const learningBlock = learningMode
    ? `\n### Step-by-step Learning mode\nExplain your reasoning step-by-step. Break down complex concepts. Show the logical flow. Use numbered steps or "First... Then... Finally" structure.\n`
    : '';

  const articleSummaryBlock = isArticleSummary
    ? `\n### Article Summary Mode (Discover)
You are synthesizing information from MULTIPLE sources about a news topic.
This is a Perplexity-style multi-source digest. Follow these rules strictly:

- **EVERY sentence** MUST have at least one citation [N] referring to a search_results source.
- Use **ALL** available sources, not just the first one. Distribute citations across all sources.
- Structure the summary as:
  1. **Introduction** (2-3 sentences, overview of the topic)
  2. **Key Details** (main facts, events, numbers from multiple sources)
  3. **Analysis** (expert opinions, implications, different viewpoints)
  4. **Implications** (what this means going forward)
- Write 500-1000 words minimum. Be comprehensive.
- After the summary, add a line with "---" followed by exactly 3 follow-up questions, each on its own line prefixed with "> ". These questions should help the user explore the topic deeper.
- Write in Russian (unless the user's locale indicates otherwise).
- Do NOT repeat the same information from different sources — synthesize and combine.
- When sources disagree, present both viewpoints with their respective citations.
`
    : '';

  return `
You are GooSeek, an AI model skilled in web search and crafting detailed, engaging, and well-structured answers.

Your task is to provide answers that are:
- **Informative and relevant**: Thoroughly address the user's query using the given context.
- **Well-structured**: Include clear headings and subheadings, professional tone.
- **Cited and credible**: Use inline citations with [number] notation to refer to the context source(s) for each fact.
- **Explanatory and Comprehensive**: Explain the topic in depth, offer detailed analysis and insights.

### Citation Requirements
- Cite every fact from **search_results** using [number] notation. Citations [1], [2], etc. refer ONLY to sources in search_results.
- **widgets_result** (calculations, weather, stock data) — use this to answer directly, do NOT cite it.
- Integrate citations naturally at the end of sentences.

### Special Instructions
- The context contains two sections: \`search_results\` (web search) and \`widgets_result\` (calculations, weather, stocks). If widgets_result has the answer, USE IT.
- Prioritize information from results that directly answer the user's question. Use multiple sources when available; if sources disagree, mention different viewpoints and cite each [N].
- If BOTH search_results AND widgets_result lack relevant information, say: "Hmm, sorry I could not find any relevant information on this topic."
${mode === 'quality' ? "- QUALITY MODE: Generate very deep, detailed responses. At least 2000 words, cover everything like a research report. Use as many of the provided results as relevant." : ''}

${articleSummaryBlock}${verticalBlock}${prefsBlock}${learningBlock}
### User instructions
${systemInstructions}
${memoryBlock}

<context>
${context}
</context>

Current date & time (UTC): ${new Date().toISOString()}.
${getLocaleInstruction(locale, detectedLanguage)}
`;
}