import json, http.client, ssl, os, logging, base64
from flask import Response, request
from searx.plugins import Plugin, PluginInfo
from searx.result_types import EngineResults
from flask_babel import gettext
from markupsafe import Markup

logger = logging.getLogger(__name__)

class SXNGPlugin(Plugin):
    id = "gemini_flash"

    def __init__(self, plg_cfg):
        super().__init__(plg_cfg)
        self.info = PluginInfo(
            id=self.id,
            name=gettext("Gemini Flash Streaming"),
            description=gettext("Live AI search answers using Google Gemini Flash"),
            preference_section="general", 
        )
        self.provider = os.getenv('LLM_PROVIDER', 'gemini').lower()
        self.api_key = os.getenv('OPENROUTER_API_KEY') if self.provider == 'openrouter' else os.getenv('GEMINI_API_KEY')
        self.model = os.getenv('GEMINI_MODEL', 'gemini-1.5-flash') if self.provider == 'gemini' else os.getenv('OPENROUTER_MODEL', 'google/gemini-2.0-flash-exp:free')
        self.max_tokens = int(os.getenv('GEMINI_MAX_TOKENS', 500))
        self.temperature = float(os.getenv('GEMINI_TEMPERATURE', 0.2))
        self.base_url = os.getenv('OPENROUTER_BASE_URL', 'openrouter.ai')

    def init(self, app):
        @app.route('/gemini-stream', methods=['POST'])
        def g_stream():
            data = request.json or {}
            context_text = data.get('context', '')
            q = data.get('q', '')

            if not self.api_key or not q:
                return Response("Error: Missing Key or Query", status=400)

            prompt = (
                f"SYSTEM: Answer USER QUERY by integrating SEARCH RESULTS with expert knowledge.\n"
                f"HIERARCHY: Use RESULTS for facts/data. Use KNOWLEDGE for context/synthesis.\n"
                f"CONSTRAINTS: <4 sentences | Dense information | Complete thoughts.\n"
                f"FALLBACK: If results are empty, answer from knowledge but note the lack of sources.\n\n"
                f"SEARCH RESULTS:\n{context_text}\n\n"
                f"USER QUERY: {q}\n\n"
                f"ANSWER:"
            )

            def generate_gemini():
                host = "generativelanguage.googleapis.com"
                path = f"/v1/models/{self.model}:streamGenerateContent?key={self.api_key}"
                try:
                    conn = http.client.HTTPSConnection(host, context=ssl.create_default_context())
                    payload = {"contents": [{"parts": [{"text": prompt}]}], "generationConfig": {"maxOutputTokens": self.max_tokens, "temperature": self.temperature}}
                    conn.request("POST", path, body=json.dumps(payload), headers={"Content-Type": "application/json"})
                    res = conn.getresponse()
                    
                    if res.status != 200:
                         return

                    decoder = json.JSONDecoder()
                    buffer = ""
                    
                    for chunk in res:
                        if not chunk: continue
                        buffer += chunk.decode('utf-8')
                        
                        while buffer:
                            buffer = buffer.lstrip()
                            if not buffer: break
                            
                            try:
                                obj, idx = decoder.raw_decode(buffer)
                                candidates = obj.get('candidates', [])
                                if candidates:
                                    content = candidates[0].get('content', {})
                                    parts = content.get('parts', [])
                                    if parts:
                                        text = parts[0].get('text', '')
                                        if text: yield text
                                
                                buffer = buffer[idx:]
                            except json.JSONDecodeError:
                                break
                                
                    conn.close()
                except Exception:
                    pass

            def generate_openrouter():
                try:
                    conn = http.client.HTTPSConnection(self.base_url, context=ssl.create_default_context())
                    payload = {
                        "model": self.model,
                        "messages": [{"role": "user", "content": prompt}],
                        "stream": True,
                        "max_tokens": self.max_tokens,
                        "temperature": self.temperature
                    }
                    headers = {
                        "Authorization": f"Bearer {self.api_key}",
                        "Content-Type": "application/json",
                        "HTTP-Referer": "https://github.com/cra88y/searxng-stream-gemini",
                        "X-Title": "SearXNG Gemini Stream"
                    }
                    conn.request("POST", "/api/v1/chat/completions", body=json.dumps(payload), headers=headers)
                    res = conn.getresponse()
                    if res.status != 200: return

                    buffer = ""
                    while True:
                        chunk = res.read(1024)
                        if not chunk: break
                        buffer += chunk.decode('utf-8')
                        while "\n" in buffer:
                            line, buffer = buffer.split("\n", 1)
                            line = line.strip()
                            if line.startswith("data: "):
                                data_str = line[6:].strip()
                                if data_str == "[DONE]": return
                                try:
                                    data_json = json.loads(data_str)
                                    content = data_json.get("choices", [{}])[0].get("delta", {}).get("content", "")
                                    if content: yield content
                                except: pass
                    conn.close()
                except Exception: pass

            generator = generate_openrouter if self.provider == 'openrouter' else generate_gemini
            return Response(generator(), mimetype='text/plain', headers={'X-Accel-Buffering': 'no'})
        return True

    def post_search(self, request, search) -> EngineResults:
        results = EngineResults()
        if not self.active or not self.api_key or search.search_query.pageno > 1:
            return results

        raw_results = search.result_container.get_ordered_results()
        context_list = [f"[{i+1}] {r.get('title')}: {r.get('content')}" for i, r in enumerate(raw_results[:6])]
        context_str = "\n".join(context_list)

        b64_context = base64.b64encode(context_str.encode('utf-8')).decode('utf-8')
        js_q = json.dumps(search.search_query.query)

        html_payload = f'''
        <article id="ai-shell" class="answer" style="display:none; margin-bottom: 1rem;">
            <p id="ai-out" style="white-space: pre-wrap;"></p>
        </article>
        <script>
        (async () => {{
            const q = {js_q};
            const b64 = "{b64_context}";
            const shell = document.getElementById('ai-shell');
            const out = document.getElementById('ai-out');

            try {{
                const ctx = new TextDecoder().decode(Uint8Array.from(atob(b64), c => c.charCodeAt(0)));
                const res = await fetch('/gemini-stream', {{
                    method: 'POST',
                    headers: {{ 'Content-Type': 'application/json' }},
                    body: JSON.stringify({{ q: q, context: ctx }})
                }});
                
                if (!res.ok) return;

                const reader = res.body.getReader();
                const decoder = new TextDecoder();
                
                while (true) {{
                    const {{done, value}} = await reader.read();
                    if (done) break;
                    
                    const chunk = decoder.decode(value);
                    if (chunk) {{
                        if (shell.style.display === 'none') shell.style.display = 'block';
                        out.innerText += chunk;
                    }}
                }}
            }} catch (e) {{ console.error(e); }}
        }})();
        </script>
        '''
        search.result_container.answers.add(results.types.Answer(answer=Markup(html_payload)))
        return results