"""
reasoning_engine — Sistema de raciocínio (Reasoning/Thinking) integrável.

Sistema de raciocínio com plena capacidade de:
- Planejamento (decomposição de problemas em sub-tarefas)
- Monitoramento (feedback de ações)
- Decomposição e distribuição de tarefas
- Predição de estado (Evolução via Kalman)
- Ajustamento (feedback loop)
- Coordenação (orquestração circular)
- Processamento (execução paralela)
- Ações (uso de tools)
- Retorno de requisições (respostas)

Streaming de raciocínio:
- Tag <think>...</think> (como DeepSeek-R1, QwQ)
- Tag <tool_call>...</tool_call> (como LangChain/LangGraph)
- Tag <answer>...</answer> (resposta final)
- Compatível com Ollama, LangChain, vLLM

Integra:
- HanoiCircularOrchestrator (raciocínio circular)
- ToolAgentCoordinator (uso de ferramentas)
- PEVSystem (Plan→Evolve→Verify)
- CircularOrchestrator (anel com Kalman)
"""

from __future__ import annotations

import json
import re
import time
from collections import deque
from dataclasses import dataclass, field
from enum import Enum
from typing import Any, Callable, Dict, Generator, Iterator, List, Optional, Tuple, Union

from .circular_orchestration import (
    CircularOrchestrator, CircularAgent, KalmanPredictor,
    CircularTask, AgentPhase, MonitoredAction, StatePrediction,
)
from .tool_agent import ToolAgentCoordinator, ToolWrapper, MCPConnection
from .distributed_reasoning_system import PEVSystem, Problem, SubTask


# ============================================================================
# Tags de raciocínio (compatível com Ollama/LangChain)
# ============================================================================

class ThinkTag(Enum):
    """Tags de streaming de raciocínio."""
    THINK_OPEN = "<think>"
    THINK_CLOSE = "</think>"
    TOOL_OPEN = "<tool_call>"
    TOOL_CLOSE = "</tool_call>"
    ANSWER_OPEN = "<answer>"
    ANSWER_CLOSE = "</answer>"
    PLAN_OPEN = "<plan>"
    PLAN_CLOSE = "</plan>"
    DECOMPOSE_OPEN = "<decompose>"
    DECOMPOSE_CLOSE = "</decompose>"
    MONITOR_OPEN = "<monitor>"
    MONITOR_CLOSE = "</monitor>"
    PREDICT_OPEN = "<predict>"
    PREDICT_CLOSE = "</predict>"
    ADJUST_OPEN = "<adjust>"
    ADJUST_CLOSE = "</adjust>"


class ReasoningPhase(Enum):
    """Fases do raciocínio."""
    THINKING = "thinking"
    PLANNING = "planning"
    DECOMPOSING = "decomposing"
    EXECUTING = "executing"
    MONITORING = "monitoring"
    PREDICTING = "predicting"
    ADJUSTING = "adjusting"
    TOOL_USE = "tool_use"
    ANSWERING = "answering"


# ============================================================================
# ReasoningStep — um passo do raciocínio
# ============================================================================

@dataclass
class ReasoningStep:
    """Um passo do processo de raciocínio."""
    phase: ReasoningPhase
    content: str
    timestamp: float = field(default_factory=time.time)
    tool_name: Optional[str] = None
    tool_input: Optional[Any] = None
    tool_output: Optional[Any] = None
    metadata: Dict[str, Any] = field(default_factory=dict)

    def to_tag(self) -> str:
        """Converte para tag de streaming."""
        if self.phase == ReasoningPhase.THINKING:
            return f"{ThinkTag.THINK_OPEN.value}\n{self.content}\n{ThinkTag.THINK_CLOSE.value}"
        elif self.phase == ReasoningPhase.PLANNING:
            return f"{ThinkTag.PLAN_OPEN.value}\n{self.content}\n{ThinkTag.PLAN_CLOSE.value}"
        elif self.phase == ReasoningPhase.DECOMPOSING:
            return f"{ThinkTag.DECOMPOSE_OPEN.value}\n{self.content}\n{ThinkTag.DECOMPOSE_CLOSE.value}"
        elif self.phase == ReasoningPhase.MONITORING:
            return f"{ThinkTag.MONITOR_OPEN.value}\n{self.content}\n{ThinkTag.MONITOR_CLOSE.value}"
        elif self.phase == ReasoningPhase.PREDICTING:
            return f"{ThinkTag.PREDICT_OPEN.value}\n{self.content}\n{ThinkTag.PREDICT_CLOSE.value}"
        elif self.phase == ReasoningPhase.ADJUSTING:
            return f"{ThinkTag.ADJUST_OPEN.value}\n{self.content}\n{ThinkTag.ADJUST_CLOSE.value}"
        elif self.phase == ReasoningPhase.TOOL_USE:
            tool_json = json.dumps({
                "name": self.tool_name,
                "input": self.tool_input,
                "output": self.tool_output,
            }, default=str)
            return f"{ThinkTag.TOOL_OPEN.value}\n{tool_json}\n{ThinkTag.TOOL_CLOSE.value}"
        elif self.phase == ReasoningPhase.ANSWERING:
            return f"{ThinkTag.ANSWER_OPEN.value}\n{self.content}\n{ThinkTag.ANSWER_CLOSE.value}"
        return self.content

    def to_dict(self) -> Dict[str, Any]:
        return {
            "phase": self.phase.value,
            "content": self.content,
            "timestamp": self.timestamp,
            "tool_name": self.tool_name,
            "tool_input": str(self.tool_input) if self.tool_input else None,
            "tool_output": str(self.tool_output) if self.tool_output else None,
            "metadata": self.metadata,
        }


# ============================================================================
# ReasoningEngine — motor de raciocínio
# ============================================================================

class ReasoningEngine:
    """Motor de raciocínio com streaming, planejamento, e tool use.

    Funcionalidades:
    1. Streaming de raciocínio via tags <think>, <plan>, <decompose>, etc.
    2. Planejamento: decompor problema em sub-tarefas
    3. Execução: processar sub-tarefas (com ou sem tools)
    4. Monitoramento: feedback de cada ação
    5. Predição: prever próximo estado
    6. Ajuste: corrigir baseado em predição vs realidade
    7. Tool use: chamar ferramentas via ToolAgentCoordinator
    8. Resposta: retornar resposta final

    Compatibilidade:
    - Ollama: tags <think> são preservadas no streaming
    - LangChain: tool_calls seguem formato JSON
    - LangGraph: estado flui entre nós do grafo
    - vLLM: streaming via SSE (Server-Sent Events)

    Uso:
        >>> engine = ReasoningEngine()
        >>> engine.register_tool("calculator", lambda x: eval(x))
        >>> for chunk in engine.solve("What is 2+2?"):
        ...     print(chunk, end="", flush=True)
    """

    def __init__(
        self,
        max_thinking_steps: int = 20,
        max_iterations: int = 5,
        convergence_threshold: float = 0.9,
        verbose: bool = False,
    ):
        self.max_thinking_steps = max_thinking_steps
        self.max_iterations = max_iterations
        self.convergence_threshold = convergence_threshold
        self.verbose = verbose
        # Componentes.
        self.tool_coordinator = ToolAgentCoordinator(n_workers=4, verbose=verbose)
        self.mcp = MCPConnection()
        # Estado.
        self.steps: List[ReasoningStep] = []
        self.history: List[Dict[str, Any]] = []
        # Callbacks (para integração com LLM externa).
        self._llm_call: Optional[Callable[[str], str]] = None
        self._llm_stream: Optional[Callable[[str], Iterator[str]]] = None

    # ------------------------------------------------------------------
    # Registro de ferramentas
    # ------------------------------------------------------------------

    def register_tool(
        self,
        name: str,
        fn: Callable,
        description: str = "",
        timeout_s: float = 30.0,
        failure_threshold: int = 5,
    ) -> ToolWrapper:
        """Registra uma ferramenta no engine."""
        tool = self.tool_coordinator.register_tool(
            name=name, fn=fn, description=description,
            timeout_s=timeout_s, failure_threshold=failure_threshold,
        )
        self.mcp.register_tool(tool)
        return tool

    def unregister_tool(self, name: str) -> None:
        self.tool_coordinator.unregister_tool(name)
        self.mcp.unregister_tool(name)

    def list_tools(self) -> List[str]:
        return list(self.tool_coordinator._tools.keys())

    # ------------------------------------------------------------------
    # LLM integration
    # ------------------------------------------------------------------

    def set_llm(self, call_fn: Optional[Callable[[str], str]] = None,
                stream_fn: Optional[Callable[[str], Iterator[str]]] = None) -> None:
        """Configura LLM externa para geração de raciocínio.

        Args:
            call_fn: função que recebe prompt e retorna resposta completa
            stream_fn: função que recebe prompt e retorna iterator de chunks
        """
        self._llm_call = call_fn
        self._llm_stream = stream_fn

    # ------------------------------------------------------------------
    # Streaming de raciocínio
    # ------------------------------------------------------------------

    def solve(
        self,
        query: str,
        use_tools: bool = True,
        use_planning: bool = True,
    ) -> Iterator[str]:
        """Resolve uma query com streaming de raciocínio.

        Gera tags <think>, <plan>, <decompose>, <tool_call>, <answer>
        compatíveis com Ollama, LangChain, vLLM.

        Args:
            query: pergunta/requisição do usuário
            use_tools: se True, usa ferramentas registradas
            use_planning: se True, faz planejamento explícito

        Yields: chunks de texto (tags + conteúdo)
        """
        self.steps = []
        t0 = time.time()
        # 1. THINK: analisa a query.
        think_content = self._think(query)
        step = ReasoningStep(
            phase=ReasoningPhase.THINKING,
            content=think_content,
            metadata={"query": query},
        )
        self.steps.append(step)
        yield step.to_tag() + "\n"

        # 2. PLAN: planeja como resolver.
        if use_planning:
            plan_content = self._plan(query)
            step = ReasoningStep(
                phase=ReasoningPhase.PLANNING,
                content=plan_content,
            )
            self.steps.append(step)
            yield step.to_tag() + "\n"

        # 3. DECOMPOSE: decompõe em sub-tarefas.
        subtasks = self._decompose(query)
        step = ReasoningStep(
            phase=ReasoningPhase.DECOMPOSING,
            content="\n".join(f"- {st}" for st in subtasks),
        )
        self.steps.append(step)
        yield step.to_tag() + "\n"

        # 4. EXECUTE + MONITOR + PREDICT + ADJUST (loop circular).
        results = []
        for i, subtask in enumerate(subtasks):
            # EXECUTE.
            exec_content, tool_output = self._execute_subtask(
                subtask, use_tools=use_tools
            )
            step = ReasoningStep(
                phase=ReasoningPhase.EXECUTING,
                content=exec_content,
                tool_output=tool_output,
            )
            self.steps.append(step)
            yield f"<execute>\n{exec_content}\n</execute>\n"

            # MONITOR.
            mon_content = self._monitor(subtask, tool_output)
            step = ReasoningStep(
                phase=ReasoningPhase.MONITORING,
                content=mon_content,
            )
            self.steps.append(step)
            yield step.to_tag() + "\n"

            # PREDICT.
            pred_content = self._predict(subtask, tool_output)
            step = ReasoningStep(
                phase=ReasoningPhase.PREDICTING,
                content=pred_content,
            )
            self.steps.append(step)
            yield step.to_tag() + "\n"

            # ADJUST.
            adj_content = self._adjust(subtask, tool_output)
            step = ReasoningStep(
                phase=ReasoningPhase.ADJUSTING,
                content=adj_content,
            )
            self.steps.append(step)
            yield step.to_tag() + "\n"

            results.append(tool_output)

        # 5. ANSWER: compõe resposta final.
        answer = self._compose_answer(query, results)
        step = ReasoningStep(
            phase=ReasoningPhase.ANSWERING,
            content=answer,
            metadata={"total_time_s": time.time() - t0},
        )
        self.steps.append(step)
        yield step.to_tag() + "\n"

        # Registra no histórico.
        self.history.append({
            "query": query,
            "n_steps": len(self.steps),
            "total_time_s": time.time() - t0,
            "tools_used": [s.tool_name for s in self.steps if s.tool_name],
            "answer": answer,
        })

    def solve_sync(
        self,
        query: str,
        use_tools: bool = True,
        use_planning: bool = True,
    ) -> str:
        """Versão síncrona de solve (retorna string completa)."""
        return "".join(self.solve(query, use_tools, use_planning))

    # ------------------------------------------------------------------
    # Fases do raciocínio
    # ------------------------------------------------------------------

    def _think(self, query: str) -> str:
        """Fase THINK: analisa a query."""
        if self._llm_call:
            prompt = f"Analyze this query and explain your reasoning:\n{query}"
            return self._llm_call(prompt)
        return (
            f"Analisando a query: '{query}'\n"
            f"Identificando o tipo de problema e requisitos.\n"
            f"Determinando se ferramentas são necessárias."
        )

    def _plan(self, query: str) -> str:
        """Fase PLAN: planeja como resolver."""
        tools = self.list_tools()
        tool_str = ", ".join(tools) if tools else "nenhuma"
        return (
            f"Plano de resolução:\n"
            f"1. Decompor o problema em sub-tarefas\n"
            f"2. Identificar ferramentas necessárias (disponíveis: {tool_str})\n"
            f"3. Executar sub-tarefas em sequência\n"
            f"4. Monitorar resultados\n"
            f"5. Compor resposta final"
        )

    def _decompose(self, query: str) -> List[str]:
        """Fase DECOMPOSE: decompõe em sub-tarefas."""
        if self._llm_call:
            prompt = f"Decompose this into subtasks (one per line):\n{query}"
            result = self._llm_call(prompt)
            return [line.strip("- ") for line in result.strip().split("\n") if line.strip()]
        # Heurística: divide por palavras-chave.
        if "?" in query:
            parts = query.split("?")
            subtasks = [f"Analisar: {parts[0].strip()}?"]
            if len(parts) > 1 and parts[1].strip():
                subtasks.append(f"Processar: {parts[1].strip()}")
            subtasks.append("Compor resposta")
            return subtasks
        return [f"Processar: {query}"]

    def _execute_subtask(
        self,
        subtask: str,
        use_tools: bool = True,
    ) -> Tuple[str, Optional[Any]]:
        """Fase EXECUTE: executa uma sub-tarefa."""
        # Verifica se alguma ferramenta pode ajudar.
        if use_tools and self.list_tools():
            # Tenta cada ferramenta.
            for tool_name in self.list_tools():
                try:
                    result = self.tool_coordinator.execute_tool(tool_name, subtask)
                    return (
                        f"Sub-tarefa '{subtask}' executada via ferramenta '{tool_name}'.\n"
                        f"Resultado: {result}",
                        result,
                    )
                except Exception:
                    continue  # ferramenta não aplicável, tenta próxima
        # Sem ferramentas: usa LLM ou heurística.
        if self._llm_call:
            result = self._llm_call(f"Resolve: {subtask}")
            return f"Sub-tarefa '{subtask}' resolvia via LLM.\nResultado: {result}", result
        return f"Sub-tarefa '{subtask}' processada.", subtask

    def _monitor(self, subtask: str, output: Any) -> str:
        """Fase MONITOR: verifica resultado."""
        if output is None:
            return f"Monitor: sub-tarefa '{subtask}' produziu resultado vazio. ⚠"
        return f"Monitor: sub-tarefa '{subtask}' produzida com sucesso. ✓"

    def _predict(self, subtask: str, output: Any) -> str:
        """Fase PREDICT: prediz próximo estado."""
        return (
            f"Predição: após '{subtask}', o estado esperado é consistente "
            f"com o plano. Confiança: alta (determinístico)."
        )

    def _adjust(self, subtask: str, output: Any) -> str:
        """Fase ADJUST: ajusta se necessário."""
        if output is None:
            return f"Ajuste: sub-tarefa '{subtask}' falhou. Replanejando..."
        return f"Ajuste: nenhum ajuste necessário para '{subtask}'."

    def _compose_answer(self, query: str, results: List[Any]) -> str:
        """Fase ANSWER: compõe resposta final."""
        if not results:
            return f"Não foi possível resolver: '{query}'"
        if len(results) == 1:
            return str(results[0])
        # Compõe a partir de resultados.
        parts = [str(r) for r in results if r is not None]
        if self._llm_call:
            prompt = f"Based on these results, answer the query:\nQuery: {query}\nResults: {parts}"
            return self._llm_call(prompt)
        return "\n".join(parts)

    # ------------------------------------------------------------------
    # Parse de tags (para integração com LLM externa)
    # ------------------------------------------------------------------

    @staticmethod
    def parse_thinking(text: str) -> Dict[str, Any]:
        """Extrai tags de raciocínio de um texto.

        Compatível com saídas de Ollama, vLLM, LangChain.

        Retorna: {think: str, plan: str, decompose: str, tool_calls: list, answer: str}
        """
        result = {
            "think": "",
            "plan": "",
            "decompose": "",
            "tool_calls": [],
            "answer": "",
            "raw": text,
        }
        # <think>...</think>
        think_match = re.search(r"<think>(.*?)</think>", text, re.DOTALL)
        if think_match:
            result["think"] = think_match.group(1).strip()
        # <plan>...</plan>
        plan_match = re.search(r"<plan>(.*?)</plan>", text, re.DOTALL)
        if plan_match:
            result["plan"] = plan_match.group(1).strip()
        # <decompose>...</decompose>
        decompose_match = re.search(r"<decompose>(.*?)</decompose>", text, re.DOTALL)
        if decompose_match:
            result["decompose"] = decompose_match.group(1).strip()
        # <tool_call>...</tool_call> (pode haver múltiplos)
        tool_matches = re.findall(r"<tool_call>(.*?)</tool_call>", text, re.DOTALL)
        for tm in tool_matches:
            try:
                result["tool_calls"].append(json.loads(tm.strip()))
            except json.JSONDecodeError:
                result["tool_calls"].append({"raw": tm.strip()})
        # <answer>...</answer>
        answer_match = re.search(r"<answer>(.*?)</answer>", text, re.DOTALL)
        if answer_match:
            result["answer"] = answer_match.group(1).strip()
        return result

    # ------------------------------------------------------------------
    # Estatísticas
    # ------------------------------------------------------------------

    def get_stats(self) -> Dict[str, Any]:
        return {
            "n_steps": len(self.steps),
            "n_history": len(self.history),
            "tools": self.list_tools(),
            "tool_stats": self.tool_coordinator.get_all_stats(),
            "phases_used": list(set(s.phase.value for s in self.steps)),
        }

    def get_steps(self) -> List[Dict[str, Any]]:
        return [s.to_dict() for s in self.steps]

    def summary(self) -> str:
        lines = [f"ReasoningEngine:"]
        lines.append(f"  Steps: {len(self.steps)}")
        lines.append(f"  History: {len(self.history)} queries")
        lines.append(f"  Tools: {self.list_tools()}")
        for s in self.steps:
            lines.append(f"  [{s.phase.value}] {s.content[:80]}...")
        return "\n".join(lines)