import os
import re
import json
import logging
from typing import Any, List, Dict, Optional

from openai import OpenAI, AzureOpenAI

# =====================================================
# LOGGING SETUP
# =====================================================

_LOG_LEVEL = os.getenv("LOG_LEVEL", "INFO").upper()

logging.basicConfig(
    level=getattr(logging, _LOG_LEVEL, logging.INFO),
    format="%(asctime)s | %(levelname)s | %(message)s"
)

logger = logging.getLogger("TLC_AGENT_UTILS")


def _log_info(message: str) -> None:
    logger.info(message)


def _log_warning(message: str) -> None:
    logger.warning(message)


def _log_error(message: str) -> None:
    logger.error(message)


# =====================================================
# JSON HELPERS
# =====================================================

def clean_json_text(text: str) -> str:
    """
    Retire les fences markdown et nettoie le texte JSON.
    """
    if not text:
        return ""

    text = str(text).strip()

    # retire fences markdown
    text = re.sub(r"^```json\s*", "", text, flags=re.IGNORECASE)
    text = re.sub(r"^```\s*", "", text)
    text = re.sub(r"\s*```$", "", text)

    return text.strip()


def safe_json_loads(text: Any):
    """
    Parse JSON robuste pour les réponses LLM.
    Retourne dict/list ou None.
    """
    if text is None:
        return None

    if isinstance(text, (dict, list)):
        return text

    text = str(text).strip()
    if not text:
        return None

    _log_info(f"safe_json_loads -> raw preview: {text[:300]}")

    text = clean_json_text(text)

    # 1) tableau JSON
    array_match = re.search(r"(\[[\s\S]*\])", text)
    if array_match:
        candidate = array_match.group(1)
        try:
            parsed = json.loads(candidate)
            _log_info("safe_json_loads -> parsed as array")
            return parsed
        except Exception as e:
            _log_warning(f"safe_json_loads -> array parse failed: {e}")

    # 2) objet JSON
    object_match = re.search(r"(\{[\s\S]*\})", text)
    if object_match:
        candidate = object_match.group(1)
        try:
            parsed = json.loads(candidate)
            _log_info("safe_json_loads -> parsed as object")
            return parsed
        except Exception as e:
            _log_warning(f"safe_json_loads -> object parse failed: {e}")

    # 3) parse direct
    try:
        parsed = json.loads(text)
        _log_info("safe_json_loads -> parsed directly")
        return parsed
    except Exception as e:
        _log_error(f"safe_json_loads -> final parse failed: {e}")
        return None


# =====================================================
# LLM CALLS
# =====================================================

def call_deepseek(
    prompt: str,
    model: str = "deepseek-chat",
    max_tokens: int = 2000
) -> str:
    """
    DeepSeek via API compatible OpenAI.
    """
    api_key = os.getenv("DEEPSEEK_API_KEY")
    if not api_key:
        _log_error("DEEPSEEK_API_KEY manquante")
        return "ERREUR: DEEPSEEK_API_KEY manquante"

    try:
        _log_info(f"Calling DeepSeek model={model}, max_tokens={max_tokens}")
        client = OpenAI(
            api_key=api_key,
            base_url="https://api.deepseek.com"
        )

        response = client.chat.completions.create(
            model=model,
            messages=[{"role": "user", "content": prompt}],
            max_tokens=max_tokens,
            temperature=0.3
        )

        content = response.choices[0].message.content or ""
        _log_info(f"DeepSeek response length: {len(content)}")
        return content.strip()

    except Exception as e:
        _log_error(f"ERREUR DEEPSEEK: {e}")
        return f"ERREUR DEEPSEEK: {e}"


def call_groq(
    prompt: str,
    model: str = "llama-3.3-70b-versatile",
    max_tokens: int = 2000
) -> str:
    """
    Groq via OpenAI-compatible endpoint.
    Évite les soucis du SDK Groq et les conflits de version.
    """
    api_key = os.getenv("GROQ_API_KEY")
    if not api_key:
        _log_error("GROQ_API_KEY manquante")
        return "ERREUR: GROQ_API_KEY manquante"

    try:
        _log_info(f"Calling Groq model={model}, max_tokens={max_tokens}")
        client = OpenAI(
            api_key=api_key,
            base_url="https://api.groq.com/openai/v1"
        )

        response = client.chat.completions.create(
            model=model,
            messages=[{"role": "user", "content": prompt}],
            max_tokens=max_tokens,
            temperature=0.3
        )

        content = response.choices[0].message.content or ""
        _log_info(f"Groq response length: {len(content)}")
        return content.strip()

    except Exception as e:
        _log_error(f"ERREUR GROQ: {e}")
        return f"ERREUR GROQ: {e}"


def call_azure_openai(
    prompt: str,
    max_tokens: int = 2000
) -> str:
    """
    Azure OpenAI.
    OPENAI_MODEL doit correspondre au nom du déploiement Azure.
    """
    api_key = os.getenv("AZUREOPENAI_API_KEY")
    endpoint = os.getenv("AZUREOPENAI_API_ENDPOINT")
    api_version = os.getenv("AZUREOPENAI_API_VERSION")
    deployment = os.getenv("OPENAI_MODEL", "gpt-4o-mini")

    if not api_key or not endpoint or not api_version:
        _log_error("Azure OpenAI credentials manquantes")
        return "ERREUR: Azure OpenAI credentials manquantes"

    try:
        _log_info(
            f"Calling Azure OpenAI deployment={deployment}, max_tokens={max_tokens}"
        )

        client = AzureOpenAI(
            api_key=api_key,
            api_version=api_version,
            azure_endpoint=endpoint
        )

        response = client.chat.completions.create(
            model=deployment,
            messages=[{"role": "user", "content": prompt}],
            max_tokens=max_tokens,
            temperature=0.3
        )

        content = response.choices[0].message.content or ""
        _log_info(f"Azure OpenAI response length: {len(content)}")
        return content.strip()

    except Exception as e:
        _log_error(f"ERREUR AZURE OPENAI: {e}")
        return f"ERREUR AZURE OPENAI: {e}"


def call_llm(
    prompt: str,
    provider: str = "azure",
    max_tokens: int = 2000
) -> str:
    """
    Routeur principal.
    """
    provider = (provider or "").lower().strip()
    _log_info(f"call_llm -> provider={provider}")

    if provider == "azure":
        return call_azure_openai(prompt, max_tokens=max_tokens)

    if provider == "groq":
        return call_groq(prompt, max_tokens=max_tokens)

    if provider == "deepseek":
        return call_deepseek(prompt, max_tokens=max_tokens)

    _log_error(f"Provider inconnu: {provider}")
    return "ERREUR: provider inconnu"


def smart_call(prompt: str, max_tokens: int = 2000) -> str:
    """
    Fallback automatique.
    Ordre conseillé: Azure -> Groq -> DeepSeek.
    """
    providers = ["azure", "groq", "deepseek"]

    for provider in providers:
        _log_info(f"smart_call -> trying {provider}")
        result = call_llm(prompt, provider=provider, max_tokens=max_tokens)

        if isinstance(result, str) and not result.startswith("ERREUR"):
            _log_info(f"smart_call -> success with {provider}")
            return result

    _log_error("smart_call -> all providers failed")
    return "ERREUR: tous les providers ont échoué"


# =====================================================
# LATEX EXTRACTION
# =====================================================

def extract_latex_blocks(text: str) -> List[str]:
    """
    Extraction rapide des blocs LaTeX:
    - $$...$$
    - \[...\]
    - $...$
    """
    if not text:
        return []

    pattern = r'\$\$([^\$]+)\$\$|\\\[(.*?)\\\]|\$([^\$]+)\$'
    matches = re.findall(pattern, text, re.DOTALL)

    equations = []
    for m in matches:
        eq = m[0] or m[1] or m[2]
        if eq and eq.strip():
            equations.append(eq.strip())

    unique = []
    seen = set()
    for eq in equations:
        if eq not in seen:
            seen.add(eq)
            unique.append(eq)

    _log_info(f"extract_latex_blocks -> found {len(unique)} equations")
    return unique


def _normalize_llm_equation_item(item: Any) -> Optional[Dict[str, str]]:
    """
    Normalise un item issu d'une réponse LLM en {"latex": "..."}.
    """
    if item is None:
        return None

    if isinstance(item, str):
        s = item.strip()
        if s:
            return {"latex": s}
        return None

    if isinstance(item, dict):
        latex = item.get("latex") or item.get("equation") or item.get("expr")
        if latex and str(latex).strip():
            return {"latex": str(latex).strip()}
        return None

    s = str(item).strip()
    if s:
        return {"latex": s}
    return None


def extract_equations_with_llm(
    text: str,
    provider: str = "azure"
) -> List[Dict[str, str]]:
    """
    Extrait des équations mathématiques via LLM.
    Retourne une liste de dicts: [{"latex": "..."}]
    """
    prompt = f"""
Tu es un assistant scientifique.

Extrait uniquement les équations mathématiques présentes dans ce texte.
Retourne STRICTEMENT un JSON valide sous cette forme:

[
  {{
    "latex": "E = mc^2"
  }}
]

Contraintes:
- Aucun texte hors JSON
- Pas de markdown
- Pas d'explication

Texte:
{text}
"""

    _log_info(f"extract_equations_with_llm -> sending to provider={provider}")

    response = call_llm(
        prompt,
        provider=provider,
        max_tokens=2000
    )

    data = safe_json_loads(response)

    if data is None:
        _log_warning("extract_equations_with_llm -> parsing failed")
        return []

    normalized: List[Dict[str, str]] = []
    if isinstance(data, list):
        for item in data:
            norm = _normalize_llm_equation_item(item)
            if norm:
                normalized.append(norm)
    else:
        norm = _normalize_llm_equation_item(data)
        if norm:
            normalized.append(norm)

    _log_info(
        f"extract_equations_with_llm -> parsed {len(normalized)} equations"
    )
    return normalized


# =====================================================
# IR HELPERS
# =====================================================

def validate_ir(ir: Any) -> bool:
    if not isinstance(ir, dict):
        return False
    if "nodes" not in ir or "edges" not in ir:
        return False
    return True


def normalize_ir(ir: Any) -> Dict[str, Any]:
    if not isinstance(ir, dict):
        _log_warning("normalize_ir -> invalid IR, building fallback shell")
        return {
            "name": "Invalid IR",
            "strategy": "fallback",
            "nodes": [],
            "edges": []
        }

    ir.setdefault("name", "Unnamed IR")
    ir.setdefault("strategy", "fallback")
    ir.setdefault("nodes", [])
    ir.setdefault("edges", [])
    return ir


def build_fallback_ir(equations: List[Any]) -> Dict[str, Any]:
    nodes = []

    for i, eq in enumerate(equations):
        latex = eq.get("latex", "") if isinstance(eq, dict) else str(eq)
        nodes.append({
            "id": f"eq_{i}",
            "type": "equation",
            "latex": latex
        })

    _log_info(f"build_fallback_ir -> built IR with {len(nodes)} nodes")

    return {
        "name": "Fallback Variant 1",
        "strategy": "fallback",
        "nodes": nodes,
        "edges": []
    }