app.py

import streamlit as st
import requests
import json
import re
import os
import operator
import traceback
from functools import lru_cache
from dotenv import load_dotenv

from langchain_groq import ChatGroq
from langchain_community.tools.tavily_search import TavilySearchResults
from langchain_core.messages import HumanMessage, SystemMessage, AIMessage, ToolMessage
# from langchain_core.prompts import ChatPromptTemplate # Not explicitly used in this version
from langchain_core.pydantic_v1 import BaseModel, Field
from langchain_core.tools import tool
from langgraph.prebuilt import ToolExecutor
from langgraph.graph import StateGraph, END

from typing import Optional, List, Dict, Any, TypedDict, Annotated

# --- Environment Variable Loading & Validation ---
load_dotenv() # Load .env file if present (for local development)

UMLS_API_KEY = os.environ.get("UMLS_API_KEY")
GROQ_API_KEY = os.environ.get("GROQ_API_KEY")
TAVILY_API_KEY = os.environ.get("TAVILY_API_KEY")

# Stop execution if essential keys are missing (crucial for HF Spaces)
missing_keys = []
if not UMLS_API_KEY: missing_keys.append("UMLS_API_KEY")
if not GROQ_API_KEY: missing_keys.append("GROQ_API_KEY")
if not TAVILY_API_KEY: missing_keys.append("TAVILY_API_KEY")

if missing_keys:
    # Use st.error which stops execution in recent Streamlit versions
    st.error(f"Missing required API Key(s): {', '.join(missing_keys)}. Please set them in Hugging Face Space Secrets or your environment variables.")
    # Ensure execution stops if st.error doesn't automatically do it in the environment
    st.stop()


# --- Configuration & Constants ---
class ClinicalAppSettings:
    APP_TITLE = "SynapseAI: Interactive Clinical Decision Support (UMLS/FDA Integrated)"
    PAGE_LAYOUT = "wide"
    MODEL_NAME = "llama3-70b-8192" # Groq Llama3 70b
    TEMPERATURE = 0.1
    MAX_SEARCH_RESULTS = 3

class ClinicalPrompts:
    # System prompt remains the same as the previous version, emphasizing structured output,
    # safety checks, guideline search, and conversational flow.
    SYSTEM_PROMPT = """
    You are SynapseAI, an expert AI clinical assistant engaged in an interactive consultation.
    Your goal is to support healthcare professionals by analyzing patient data, providing differential diagnoses, suggesting evidence-based management plans, and identifying risks according to current standards of care.

    **Core Directives for this Conversation:**
    1.  **Analyze Sequentially:** Process information turn-by-turn. Base your responses on the *entire* conversation history.
    2.  **Seek Clarity:** If the provided information is insufficient or ambiguous for a safe assessment, CLEARLY STATE what specific additional information or clarification is needed. Do NOT guess or make unsafe assumptions.
    3.  **Structured Assessment (When Ready):** When you have sufficient information and have performed necessary checks (like interactions, guideline searches), provide a comprehensive assessment using the following JSON structure. Output this JSON structure as the primary content of your response when you are providing the full analysis. Do NOT output incomplete JSON. If you need to ask a question or perform a tool call first, do that instead of outputting this structure.
        ```json
        {
          "assessment": "Concise summary of the patient's presentation and key findings based on the conversation.",
          "differential_diagnosis": [
            {"diagnosis": "Primary Diagnosis", "likelihood": "High/Medium/Low", "rationale": "Supporting evidence from conversation..."},
            {"diagnosis": "Alternative Diagnosis 1", "likelihood": "Medium/Low", "rationale": "Supporting/Refuting evidence..."},
            {"diagnosis": "Alternative Diagnosis 2", "likelihood": "Low", "rationale": "Why it's less likely but considered..."}
          ],
          "risk_assessment": {
            "identified_red_flags": ["List any triggered red flags based on input and analysis"],
            "immediate_concerns": ["Specific urgent issues requiring attention (e.g., sepsis risk, ACS rule-out)"],
            "potential_complications": ["Possible future issues based on presentation"]
          },
          "recommended_plan": {
            "investigations": ["List specific lab tests or imaging required. Use 'order_lab_test' tool."],
            "therapeutics": ["Suggest specific treatments or prescriptions. Use 'prescribe_medication' tool. MUST check interactions first using 'check_drug_interactions'."],
            "consultations": ["Recommend specialist consultations if needed."],
            "patient_education": ["Key points for patient communication."]
          },
          "rationale_summary": "Justification for assessment/plan. **Crucially, if relevant (e.g., ACS, sepsis, common infections), use 'tavily_search_results' to find and cite current clinical practice guidelines (e.g., 'latest ACC/AHA chest pain guidelines 202X', 'Surviving Sepsis Campaign guidelines') supporting your recommendations.** Include summary of guideline findings here.",
          "interaction_check_summary": "Summary of findings from 'check_drug_interactions' if performed."
        }
        ```
    4.  **Safety First - Interactions:** BEFORE suggesting a new prescription via `prescribe_medication`, you MUST FIRST use `check_drug_interactions` in a preceding or concurrent tool call. Report the findings from the interaction check. If significant interactions exist, modify the plan or state the contraindication clearly.
    5.  **Safety First - Red Flags:** Use the `flag_risk` tool IMMEDIATELY if critical red flags requiring urgent action are identified at any point in the conversation.
    6.  **Tool Use:** Employ tools (`order_lab_test`, `prescribe_medication`, `check_drug_interactions`, `flag_risk`, `tavily_search_results`) logically within the conversational flow. Wait for tool results before proceeding if the result is needed for the next step (e.g., wait for interaction check before confirming prescription in the structured JSON).
    7.  **Evidence & Guidelines:** Actively use `tavily_search_results` not just for general knowledge, but specifically to query for and incorporate **current clinical practice guidelines** relevant to the patient's presentation (e.g., chest pain, shortness of breath, suspected infection). Summarize findings in the `rationale_summary` when providing the structured output.
    8.  **Conciseness & Flow:** Be medically accurate and concise. Use standard terminology. Respond naturally in conversation (asking questions, acknowledging info) until ready for the full structured JSON output.
    """

# --- UMLS/RxNorm & OpenFDA API Helper Functions ---
UMLS_AUTH_ENDPOINT = "https://utslogin.nlm.nih.gov/cas/v1/api-key" # May not be needed if using apiKey directly
RXNORM_API_BASE = "https://rxnav.nlm.nih.gov/REST"
OPENFDA_API_BASE = "https://api.fda.gov/drug/label.json"

@lru_cache(maxsize=256) # Cache RxCUI lookups
def get_rxcui(drug_name: str) -> Optional[str]:
    """Uses RxNorm API to find the RxCUI for a given drug name."""
    if not drug_name or not isinstance(drug_name, str): return None
    drug_name = drug_name.strip()
    if not drug_name: return None

    print(f"RxNorm Lookup for: '{drug_name}'")
    try:
        params = {"name": drug_name, "search": 1} # Search for concepts related to the name
        response = requests.get(f"{RXNORM_API_BASE}/rxcui.json", params=params, timeout=10)
        response.raise_for_status()
        data = response.json()
        if data and "idGroup" in data and "rxnormId" in data["idGroup"]:
            rxcui = data["idGroup"]["rxnormId"][0]
            print(f"  Found RxCUI: {rxcui} for '{drug_name}'")
            return rxcui
        else: # Fallback search
            params = {"name": drug_name}; response = requests.get(f"{RXNORM_API_BASE}/drugs.json", params=params, timeout=10)
            response.raise_for_status(); data = response.json()
            if data and "drugGroup" in data and "conceptGroup" in data["drugGroup"]:
                for group in data["drugGroup"]["conceptGroup"]:
                    if group.get("tty") in ["SBD", "SCD", "GPCK", "BPCK", "IN", "MIN", "PIN"]:
                        if "conceptProperties" in group and group["conceptProperties"]:
                            rxcui = group["conceptProperties"][0].get("rxcui")
                            if rxcui: print(f"  Found RxCUI (via /drugs): {rxcui} for '{drug_name}'"); return rxcui
        print(f"  RxCUI not found for '{drug_name}'.")
        return None
    except requests.exceptions.RequestException as e: print(f"  Error fetching RxCUI for '{drug_name}': {e}"); return None
    except json.JSONDecodeError as e: print(f"  Error decoding RxNorm JSON response for '{drug_name}': {e}"); return None
    except Exception as e: print(f"  Unexpected error in get_rxcui for '{drug_name}': {e}"); return None

@lru_cache(maxsize=128) # Cache OpenFDA lookups
def get_openfda_label(rxcui: Optional[str] = None, drug_name: Optional[str] = None) -> Optional[dict]:
    """Fetches drug label information from OpenFDA using RxCUI or drug name."""
    if not rxcui and not drug_name: return None
    print(f"OpenFDA Label Lookup for: RXCUI={rxcui}, Name={drug_name}")
    search_terms = []
    if rxcui: search_terms.append(f'spl_rxnorm_code:"{rxcui}" OR openfda.rxcui:"{rxcui}"')
    if drug_name: search_terms.append(f'(openfda.brand_name:"{drug_name.lower()}" OR openfda.generic_name:"{drug_name.lower()}")')
    search_query = " OR ".join(search_terms); params = {"search": search_query, "limit": 1}
    try:
        response = requests.get(OPENFDA_API_BASE, params=params, timeout=15)
        response.raise_for_status(); data = response.json()
        if data and "results" in data and data["results"]: print(f"  Found OpenFDA label for query: {search_query}"); return data["results"][0]
        print(f"  No OpenFDA label found for query: {search_query}"); return None
    except requests.exceptions.RequestException as e: print(f"  Error fetching OpenFDA label: {e}"); return None
    except json.JSONDecodeError as e: print(f"  Error decoding OpenFDA JSON response: {e}"); return None
    except Exception as e: print(f"  Unexpected error in get_openfda_label: {e}"); return None

def search_text_list(text_list: Optional[List[str]], search_terms: List[str]) -> List[str]:
    """ Case-insensitive search for any search_term within a list of text strings. Returns snippets. """
    found_snippets = []
    if not text_list or not search_terms: return found_snippets
    search_terms_lower = [str(term).lower() for term in search_terms if term]
    for text_item in text_list:
        if not isinstance(text_item, str): continue
        text_item_lower = text_item.lower()
        for term in search_terms_lower:
            if term in text_item_lower:
                start_index = text_item_lower.find(term); snippet_start = max(0, start_index - 50)
                snippet_end = min(len(text_item), start_index + len(term) + 100); snippet = text_item[snippet_start:snippet_end]
                snippet = snippet.replace(term, f"**{term}**", 1); found_snippets.append(f"...{snippet}...")
                break
    return found_snippets

# --- Other Helper Functions ---
def parse_bp(bp_string: str) -> Optional[tuple[int, int]]:
    """Parses BP string like '120/80' into (systolic, diastolic) integers."""
    if not isinstance(bp_string, str): return None
    match = re.match(r"(\d{1,3})\s*/\s*(\d{1,3})", bp_string.strip())
    if match: return int(match.group(1)), int(match.group(2))
    return None

def check_red_flags(patient_data: dict) -> List[str]:
    """Checks patient data against predefined red flags."""
    flags = []
    if not patient_data: return flags
    symptoms = patient_data.get("hpi", {}).get("symptoms", [])
    vitals = patient_data.get("vitals", {})
    history = patient_data.get("pmh", {}).get("conditions", "")
    symptoms_lower = [str(s).lower() for s in symptoms if isinstance(s, str)]

    if "chest pain" in symptoms_lower: flags.append("Red Flag: Chest Pain reported.")
    if "shortness of breath" in symptoms_lower: flags.append("Red Flag: Shortness of Breath reported.")
    if "severe headache" in symptoms_lower: flags.append("Red Flag: Severe Headache reported.")
    if "sudden vision loss" in symptoms_lower: flags.append("Red Flag: Sudden Vision Loss reported.")
    if "weakness on one side" in symptoms_lower: flags.append("Red Flag: Unilateral Weakness reported (potential stroke).")
    if "hemoptysis" in symptoms_lower: flags.append("Red Flag: Hemoptysis (coughing up blood).")
    if "syncope" in symptoms_lower: flags.append("Red Flag: Syncope (fainting).")

    if vitals:
        temp = vitals.get("temp_c"); hr = vitals.get("hr_bpm"); rr = vitals.get("rr_rpm")
        spo2 = vitals.get("spo2_percent"); bp_str = vitals.get("bp_mmhg")
        if temp is not None and temp >= 38.5: flags.append(f"Red Flag: Fever ({temp}°C).")
        if hr is not None and hr >= 120: flags.append(f"Red Flag: Tachycardia ({hr} bpm).")
        if hr is not None and hr <= 50: flags.append(f"Red Flag: Bradycardia ({hr} bpm).")
        if rr is not None and rr >= 24: flags.append(f"Red Flag: Tachypnea ({rr} rpm).")
        if spo2 is not None and spo2 <= 92: flags.append(f"Red Flag: Hypoxia ({spo2}%).")
        if bp_str:
            bp = parse_bp(bp_str)
            if bp:
                if bp[0] >= 180 or bp[1] >= 110: flags.append(f"Red Flag: Hypertensive Urgency/Emergency (BP: {bp_str} mmHg).")
                if bp[0] <= 90 or bp[1] <= 60: flags.append(f"Red Flag: Hypotension (BP: {bp_str} mmHg).")

    if history and isinstance(history, str):
        history_lower = history.lower()
        if "history of mi" in history_lower and "chest pain" in symptoms_lower: flags.append("Red Flag: History of MI with current Chest Pain.")
        if "history of dvt/pe" in history_lower and "shortness of breath" in symptoms_lower: flags.append("Red Flag: History of DVT/PE with current Shortness of Breath.")

    return list(set(flags))

def format_patient_data_for_prompt(data: dict) -> str:
    """Formats the patient dictionary into a readable string for the LLM."""
    if not data: return "No patient data provided."
    prompt_str = ""
    for key, value in data.items():
        section_title = key.replace('_', ' ').title()
        if isinstance(value, dict) and value:
            has_content = any(sub_value for sub_value in value.values())
            if has_content:
                prompt_str += f"**{section_title}:**\n"
                for sub_key, sub_value in value.items():
                     if sub_value: prompt_str += f"  - {sub_key.replace('_', ' ').title()}: {sub_value}\n"
        elif isinstance(value, list) and value:
             prompt_str += f"**{section_title}:** {', '.join(map(str, value))}\n"
        elif value and not isinstance(value, dict):
             prompt_str += f"**{section_title}:** {value}\n"
    return prompt_str.strip()


# --- Tool Definitions ---

# Pydantic models
class LabOrderInput(BaseModel):
    test_name: str = Field(..., description="Specific name of the lab test or panel (e.g., 'CBC', 'BMP', 'Troponin I', 'Urinalysis', 'D-dimer').")
    reason: str = Field(..., description="Clinical justification for ordering the test (e.g., 'Rule out infection', 'Assess renal function', 'Evaluate for ACS', 'Assess for PE').")
    priority: str = Field("Routine", description="Priority of the test (e.g., 'STAT', 'Routine').")

class PrescriptionInput(BaseModel):
    medication_name: str = Field(..., description="Name of the medication.")
    dosage: str = Field(..., description="Dosage amount and unit (e.g., '500 mg', '10 mg', '81 mg').")
    route: str = Field(..., description="Route of administration (e.g., 'PO', 'IV', 'IM', 'Topical', 'SL').")
    frequency: str = Field(..., description="How often the medication should be taken (e.g., 'BID', 'QDaily', 'Q4-6H PRN', 'once').")
    duration: str = Field("As directed", description="Duration of treatment (e.g., '7 days', '1 month', 'Ongoing', 'Until follow-up').")
    reason: str = Field(..., description="Clinical indication for the prescription.")

class InteractionCheckInput(BaseModel):
    potential_prescription: str = Field(..., description="The name of the NEW medication being considered for prescribing.")
    current_medications: Optional[List[str]] = Field(None, description="List of patient's current medication names (populated from state).")
    allergies: Optional[List[str]] = Field(None, description="List of patient's known allergies (populated from state).")

class FlagRiskInput(BaseModel):
    risk_description: str = Field(..., description="Specific critical risk identified (e.g., 'Suspected Sepsis', 'Acute Coronary Syndrome', 'Stroke Alert').")
    urgency: str = Field("High", description="Urgency level (e.g., 'Critical', 'High', 'Moderate').")

# Tool functions
@tool("order_lab_test", args_schema=LabOrderInput)
def order_lab_test(test_name: str, reason: str, priority: str = "Routine") -> str:
    """Orders a specific lab test with clinical justification and priority."""
    print(f"Executing order_lab_test: {test_name}, Reason: {reason}, Priority: {priority}")
    return json.dumps({"status": "success", "message": f"Lab Ordered: {test_name} ({priority})", "details": f"Reason: {reason}"})

@tool("prescribe_medication", args_schema=PrescriptionInput)
def prescribe_medication(medication_name: str, dosage: str, route: str, frequency: str, duration: str, reason: str) -> str:
    """Prescribes a medication with detailed instructions and clinical indication. IMPORTANT: Requires prior interaction check."""
    print(f"Executing prescribe_medication: {medication_name} {dosage}...")
    return json.dumps({"status": "success", "message": f"Prescription Prepared: {medication_name} {dosage} {route} {frequency}", "details": f"Duration: {duration}. Reason: {reason}"})

@tool("check_drug_interactions", args_schema=InteractionCheckInput)
def check_drug_interactions(potential_prescription: str, current_medications: Optional[List[str]] = None, allergies: Optional[List[str]] = None) -> str:
    """
    Checks for potential drug-drug and drug-allergy interactions using RxNorm API for normalization
    and OpenFDA drug labels for interaction/warning text. REQUIRES UMLS_API_KEY environment variable.
    """
    print(f"\n--- Executing REAL check_drug_interactions ---")
    print(f"Checking potential prescription: '{potential_prescription}'")
    warnings = []
    potential_med_lower = potential_prescription.lower().strip()
    current_meds_list = current_medications or []; allergies_list = allergies or []
    current_med_names_lower = []
    for med in current_meds_list:
         match = re.match(r"^\s*([a-zA-Z\-]+)", str(med));
         if match: current_med_names_lower.append(match.group(1).lower())
    allergies_lower = [str(a).lower().strip() for a in allergies_list if a]
    print(f"  Against Current Meds (names): {current_med_names_lower}"); print(f"  Against Allergies: {allergies_lower}")

    print(f"  Step 1: Normalizing '{potential_prescription}'..."); potential_rxcui = get_rxcui(potential_prescription)
    potential_label = get_openfda_label(rxcui=potential_rxcui, drug_name=potential_prescription)
    if not potential_rxcui and not potential_label: warnings.append(f"INFO: Could not reliably identify '{potential_prescription}'. Checks may be incomplete.")

    print("  Step 2: Performing Allergy Check...");
    for allergy in allergies_lower:
        if allergy == potential_med_lower: warnings.append(f"CRITICAL ALLERGY (Name Match): Patient allergic to '{allergy}'. Potential prescription is '{potential_prescription}'.")
        elif allergy in ["penicillin", "pcns"] and potential_med_lower in ["amoxicillin", "ampicillin", "augmentin", "piperacillin"]: warnings.append(f"POTENTIAL CROSS-ALLERGY: Patient allergic to Penicillin. High risk with '{potential_prescription}'.")
        elif allergy == "sulfa" and potential_med_lower in ["sulfamethoxazole", "bactrim", "sulfasalazine"]: warnings.append(f"POTENTIAL CROSS-ALLERGY: Patient allergic to Sulfa. High risk with '{potential_prescription}'.")
        elif allergy in ["nsaids", "aspirin"] and potential_med_lower in ["ibuprofen", "naproxen", "ketorolac", "diclofenac"]: warnings.append(f"POTENTIAL CROSS-ALLERGY: Patient allergic to NSAIDs/Aspirin. Risk with '{potential_prescription}'.")
    if potential_label:
        contraindications = potential_label.get("contraindications"); warnings_section = potential_label.get("warnings_and_cautions") or potential_label.get("warnings")
        if contraindications:
            allergy_mentions_ci = search_text_list(contraindications, allergies_lower)
            if allergy_mentions_ci: warnings.append(f"ALLERGY RISK (Contraindication Found): Label for '{potential_prescription}' mentions contraindication potentially related to patient allergies: {'; '.join(allergy_mentions_ci)}")
        if warnings_section:
            allergy_mentions_warn = search_text_list(warnings_section, allergies_lower)
            if allergy_mentions_warn: warnings.append(f"ALLERGY RISK (Warning Found): Label for '{potential_prescription}' mentions warnings potentially related to patient allergies: {'; '.join(allergy_mentions_warn)}")

    print("  Step 3: Performing Drug-Drug Interaction Check...")
    if potential_rxcui or potential_label:
        for current_med_name in current_med_names_lower:
            if not current_med_name or current_med_name == potential_med_lower: continue
            print(f"    Checking interaction between '{potential_prescription}' and '{current_med_name}'...")
            current_rxcui = get_rxcui(current_med_name); current_label = get_openfda_label(rxcui=current_rxcui, drug_name=current_med_name)
            search_terms_for_current = [current_med_name];
            if current_rxcui: search_terms_for_current.append(current_rxcui)
            search_terms_for_potential = [potential_med_lower];
            if potential_rxcui: search_terms_for_potential.append(potential_rxcui)
            interaction_found_flag = False
            if potential_label and potential_label.get("drug_interactions"):
                interaction_mentions = search_text_list(potential_label.get("drug_interactions"), search_terms_for_current)
                if interaction_mentions: warnings.append(f"Potential Interaction ({potential_prescription.capitalize()} Label): Mentions '{current_med_name.capitalize()}'. Snippets: {'; '.join(interaction_mentions)}"); interaction_found_flag = True
            if current_label and current_label.get("drug_interactions") and not interaction_found_flag:
                interaction_mentions = search_text_list(current_label.get("drug_interactions"), search_terms_for_potential)
                if interaction_mentions: warnings.append(f"Potential Interaction ({current_med_name.capitalize()} Label): Mentions '{potential_prescription.capitalize()}'. Snippets: {'; '.join(interaction_mentions)}")
    else: warnings.append(f"INFO: Drug-drug interaction check skipped for '{potential_prescription}' as it could not be identified via RxNorm/OpenFDA.")

    final_warnings = list(set(warnings)); status = "warning" if any("CRITICAL" in w or "Interaction" in w or "RISK" in w for w in final_warnings) else "clear"
    if not final_warnings: status = "clear"
    message = f"Interaction/Allergy check for '{potential_prescription}': {len(final_warnings)} potential issue(s) identified using RxNorm/OpenFDA." if final_warnings else f"No major interactions or allergy issues identified for '{potential_prescription}' based on RxNorm/OpenFDA lookup."
    print(f"--- Interaction Check Complete for '{potential_prescription}' ---")
    return json.dumps({"status": status, "message": message, "warnings": final_warnings})

@tool("flag_risk", args_schema=FlagRiskInput)
def flag_risk(risk_description: str, urgency: str) -> str:
    """Flags a critical risk identified during analysis for immediate attention."""
    print(f"Executing flag_risk: {risk_description}, Urgency: {urgency}")
    st.error(f"🚨 **{urgency.upper()} RISK FLAGGED by AI:** {risk_description}", icon="🚨")
    return json.dumps({"status": "flagged", "message": f"Risk '{risk_description}' flagged with {urgency} urgency."})

# Initialize Search Tool
search_tool = TavilySearchResults(max_results=ClinicalAppSettings.MAX_SEARCH_RESULTS, name="tavily_search_results")

# --- LangGraph Setup ---
class AgentState(TypedDict):
    messages: Annotated[list[Any], operator.add]; patient_data: Optional[dict]
tools = [order_lab_test, prescribe_medication, check_drug_interactions, flag_risk, search_tool]
tool_executor = ToolExecutor(tools)
model = ChatGroq(temperature=ClinicalAppSettings.TEMPERATURE, model=ClinicalAppSettings.MODEL_NAME)
model_with_tools = model.bind_tools(tools)

# --- Graph Nodes ---
def agent_node(state: AgentState):
    print("\n---AGENT NODE---")
    current_messages = state['messages']
    if not current_messages or not isinstance(current_messages[0], SystemMessage):
        print("Prepending System Prompt."); current_messages = [SystemMessage(content=ClinicalPrompts.SYSTEM_PROMPT)] + current_messages
    print(f"Invoking LLM with {len(current_messages)} messages.")
    try:
        response = model_with_tools.invoke(current_messages)
        print(f"Agent Raw Response Type: {type(response)}")
        if hasattr(response, 'tool_calls') and response.tool_calls: print(f"Agent Response Tool Calls: {response.tool_calls}")
        else: print("Agent Response: No tool calls.")
    except Exception as e:
        print(f"ERROR in agent_node during LLM invocation: {type(e).__name__} - {e}"); traceback.print_exc()
        error_message = AIMessage(content=f"Sorry, an internal error occurred while processing the request: {type(e).__name__}")
        return {"messages": [error_message]}
    return {"messages": [response]}

def tool_node(state: AgentState):
    print("\n---TOOL NODE---")
    tool_messages = []; last_message = state['messages'][-1]
    if not isinstance(last_message, AIMessage) or not getattr(last_message, 'tool_calls', None):
        print("Warning: Tool node called unexpectedly without tool calls."); return {"messages": []}
    tool_calls = last_message.tool_calls; print(f"Tool calls received: {json.dumps(tool_calls, indent=2)}")
    prescriptions_requested = {}; interaction_checks_requested = {}
    for call in tool_calls:
        tool_name = call.get('name'); tool_args = call.get('args', {})
        if tool_name == 'prescribe_medication': med_name = tool_args.get('medication_name', '').lower();
        if med_name: prescriptions_requested[med_name] = call
        elif tool_name == 'check_drug_interactions': potential_med = tool_args.get('potential_prescription', '').lower()
        if potential_med: interaction_checks_requested[potential_med] = call
    valid_tool_calls_for_execution = []; blocked_ids = set()
    for med_name, prescribe_call in prescriptions_requested.items():
        if med_name not in interaction_checks_requested:
            st.error(f"**Safety Violation:** AI attempted to prescribe '{med_name}' without requesting `check_drug_interactions` in the *same turn*. Prescription blocked.")
            error_msg = ToolMessage(content=json.dumps({"status": "error", "message": f"Interaction check for '{med_name}' must be requested *before or alongside* the prescription call."}), tool_call_id=prescribe_call['id'], name=prescribe_call['name'])
            tool_messages.append(error_msg); blocked_ids.add(prescribe_call['id'])
    valid_tool_calls_for_execution = [call for call in tool_calls if call['id'] not in blocked_ids]
    patient_data = state.get("patient_data", {}); patient_meds_full = patient_data.get("medications", {}).get("current", []); patient_allergies = patient_data.get("allergies", [])
    for call in valid_tool_calls_for_execution:
         if call['name'] == 'check_drug_interactions':
             if 'args' not in call: call['args'] = {}
             call['args']['current_medications'] = patient_meds_full; call['args']['allergies'] = patient_allergies; print(f"Augmented interaction check args for call ID {call['id']}")
    if valid_tool_calls_for_execution:
        print(f"Attempting to execute {len(valid_tool_calls_for_execution)} tools: {[c['name'] for c in valid_tool_calls_for_execution]}")
        try:
            responses = tool_executor.batch(valid_tool_calls_for_execution, return_exceptions=True)
            for call, resp in zip(valid_tool_calls_for_execution, responses):
                tool_call_id = call['id']; tool_name = call['name']
                if isinstance(resp, Exception):
                    error_type = type(resp).__name__; error_str = str(resp); print(f"ERROR executing tool '{tool_name}' (ID: {tool_call_id}): {error_type} - {error_str}"); traceback.print_exc()
                    st.error(f"Error executing action '{tool_name}': {error_type}"); error_content = json.dumps({"status": "error", "message": f"Failed to execute '{tool_name}': {error_type} - {error_str}"})
                    tool_messages.append(ToolMessage(content=error_content, tool_call_id=tool_call_id, name=tool_name))
                    if isinstance(resp, AttributeError) and "'dict' object has no attribute 'tool'" in error_str: print("\n *** DETECTED SPECIFIC ATTRIBUTE ERROR ('dict' object has no attribute 'tool') *** \n")
                else:
                    print(f"Tool '{tool_name}' (ID: {tool_call_id}) executed successfully."); content_str = str(resp); tool_messages.append(ToolMessage(content=content_str, tool_call_id=tool_call_id, name=tool_name))
        except Exception as e:
            print(f"CRITICAL UNEXPECTED ERROR within tool_node logic: {type(e).__name__} - {e}"); traceback.print_exc(); st.error(f"Critical internal error processing actions: {e}")
            error_content = json.dumps({"status": "error", "message": f"Internal error processing tools: {e}"}); processed_ids = {msg.tool_call_id for msg in tool_messages}
            for call in valid_tool_calls_for_execution:
                 if call['id'] not in processed_ids: tool_messages.append(ToolMessage(content=error_content, tool_call_id=call['id'], name=call['name']))
    print(f"Returning {len(tool_messages)} tool messages."); return {"messages": tool_messages}

# --- Graph Edges (Routing Logic) ---
def should_continue(state: AgentState) -> str:
    print("\n---ROUTING DECISION---"); last_message = state['messages'][-1] if state['messages'] else None
    if not isinstance(last_message, AIMessage): return "end_conversation_turn"
    if "Sorry, an internal error occurred" in last_message.content: return "end_conversation_turn"
    if getattr(last_message, 'tool_calls', None): return "continue_tools"
    else: return "end_conversation_turn"

# --- Graph Definition & Compilation ---
workflow = StateGraph(AgentState); workflow.add_node("agent", agent_node); workflow.add_node("tools", tool_node)
workflow.set_entry_point("agent"); workflow.add_conditional_edges("agent", should_continue, {"continue_tools": "tools", "end_conversation_turn": END})
workflow.add_edge("tools", "agent"); app = workflow.compile(); print("LangGraph compiled successfully.")

# --- Streamlit UI ---
def main():
    st.set_page_config(page_title=ClinicalAppSettings.APP_TITLE, layout=ClinicalAppSettings.PAGE_LAYOUT)
    st.title(f"🩺 {ClinicalAppSettings.APP_TITLE}")
    st.caption(f"Interactive Assistant | LangGraph/Groq/Tavily/UMLS/OpenFDA | Model: {ClinicalAppSettings.MODEL_NAME}")
    if "messages" not in st.session_state: st.session_state.messages = []
    if "patient_data" not in st.session_state: st.session_state.patient_data = None
    if "graph_app" not in st.session_state: st.session_state.graph_app = app

    # --- Patient Data Input Sidebar ---
    with st.sidebar:
        st.header("📄 Patient Intake Form")
        # Input fields (Demographics, HPI, History, Meds/Allergies, Social/Family, Vitals/Exam)
        st.subheader("Demographics"); age = st.number_input("Age", 0, 120, 55); sex = st.selectbox("Sex", ["Male", "Female", "Other"])
        st.subheader("HPI"); chief_complaint = st.text_input("Chief Complaint", "Chest pain"); hpi_details = st.text_area("HPI Details", "55 y/o male...", height=150); symptoms = st.multiselect("Symptoms", ["Nausea", "Diaphoresis", "SOB", "Dizziness"], default=["Nausea", "Diaphoresis"])
        st.subheader("History"); pmh = st.text_area("PMH", "HTN, HLD, DM2, MI"); psh = st.text_area("PSH", "Appendectomy")
        st.subheader("Meds & Allergies"); current_meds_str = st.text_area("Current Meds", "Lisinopril 10mg daily\nMetformin 1000mg BID\nAtorvastatin 40mg daily"); allergies_str = st.text_area("Allergies", "Penicillin (rash), Sulfa")
        st.subheader("Social/Family"); social_history = st.text_area("SH", "Smoker"); family_history = st.text_area("FHx", "Father MI")
        st.subheader("Vitals & Exam"); col1, col2 = st.columns(2);
        with col1: temp_c = st.number_input("Temp C", 35.0, 42.0, 36.8, format="%.1f"); hr_bpm = st.number_input("HR", 30, 250, 95); rr_rpm = st.number_input("RR", 5, 50, 18)
        with col2: bp_mmhg = st.text_input("BP", "155/90"); spo2_percent = st.number_input("SpO2", 70, 100, 96); pain_scale = st.slider("Pain", 0, 10, 8)
        exam_notes = st.text_area("Exam Notes", "Awake, alert...", height=100)

        if st.button("Start/Update Consultation"):
            current_meds_list = [med.strip() for med in current_meds_str.split('\n') if med.strip()]
            current_med_names_only = [];
            for med in current_meds_list: match = re.match(r"^\s*([a-zA-Z\-]+)", med);
            if match: current_med_names_only.append(match.group(1).lower())
            allergies_list = []
            for a in allergies_str.split(','):
                cleaned_allergy = a.strip();
                if cleaned_allergy: match = re.match(r"^\s*([a-zA-Z\-\s/]+)(?:\s*\(.*\))?", cleaned_allergy); name_part = match.group(1).strip().lower() if match else cleaned_allergy.lower(); allergies_list.append(name_part)
            st.session_state.patient_data = { "demographics": {"age": age, "sex": sex}, "hpi": {"chief_complaint": chief_complaint, "details": hpi_details, "symptoms": symptoms}, "pmh": {"conditions": pmh}, "psh": {"procedures": psh}, "medications": {"current": current_meds_list, "names_only": current_med_names_only}, "allergies": allergies_list, "social_history": {"details": social_history}, "family_history": {"details": family_history}, "vitals": { "temp_c": temp_c, "hr_bpm": hr_bpm, "bp_mmhg": bp_mmhg, "rr_rpm": rr_rpm, "spo2_percent": spo2_percent, "pain_scale": pain_scale}, "exam_findings": {"notes": exam_notes} }
            red_flags = check_red_flags(st.session_state.patient_data); st.sidebar.markdown("---")
            if red_flags: st.sidebar.warning("**Initial Red Flags:**"); [st.sidebar.warning(f"- {flag.replace('Red Flag: ','')}") for flag in red_flags]
            else: st.sidebar.success("No immediate red flags.")
            initial_prompt = "Initiate consultation for the patient described in the intake form. Review data and begin analysis."
            st.session_state.messages = [HumanMessage(content=initial_prompt)]; st.success("Patient data loaded/updated.")

    # --- Main Chat Interface Area ---
    st.header("💬 Clinical Consultation")
    # Display loop - REMOVED key= ARGUMENT
    for msg in st.session_state.messages:
        if isinstance(msg, HumanMessage):
            with st.chat_message("user"): st.markdown(msg.content) # No key
        elif isinstance(msg, AIMessage):
            with st.chat_message("assistant"): # No key
                ai_content = msg.content; structured_output = None
                try:
                    json_match = re.search(r"```json\s*(\{.*?\})\s*```", ai_content, re.DOTALL | re.IGNORECASE)
                    if json_match:
                        json_str = json_match.group(1); prefix = ai_content[:json_match.start()].strip(); suffix = ai_content[json_match.end():].strip()
                        if prefix: st.markdown(prefix)
                        structured_output = json.loads(json_str)
                        if suffix: st.markdown(suffix)
                    elif ai_content.strip().startswith("{") and ai_content.strip().endswith("}"):
                         structured_output = json.loads(ai_content); ai_content = ""
                    else: st.markdown(ai_content)
                except Exception as e: st.markdown(ai_content); print(f"Error parsing/displaying AI JSON: {e}")
                if structured_output and isinstance(structured_output, dict):
                    st.divider(); st.subheader("📊 AI Analysis & Recommendations") # Display logic for JSON...
                    cols = st.columns(2)
                    with cols[0]: # Assessment, DDx, Risk
                        st.markdown("**Assessment:**"); st.markdown(f"> {structured_output.get('assessment', 'N/A')}")
                        st.markdown("**Differential Diagnosis:**"); ddx = structured_output.get('differential_diagnosis', []);
                        if ddx: [st.expander(f"{'🥇🥈🥉'[('High','Medium','Low').index(item.get('likelihood','Low')[0])] if item.get('likelihood','?')[0] in 'HML' else '?'} {item.get('diagnosis', 'Unknown')} ({item.get('likelihood','?')})").write(f"**Rationale:** {item.get('rationale', 'N/A')}") for item in ddx]
                        else: st.info("No DDx provided.")
                        st.markdown("**Risk Assessment:**"); risk = structured_output.get('risk_assessment', {}); flags=risk.get('identified_red_flags',[]); concerns=risk.get("immediate_concerns",[]); comps=risk.get("potential_complications",[])
                        if flags: st.warning(f"**Flags:** {', '.join(flags)}")
                        if concerns: st.warning(f"**Concerns:** {', '.join(concerns)}")
                        if comps: st.info(f"**Potential Complications:** {', '.join(comps)}")
                        if not flags and not concerns: st.success("No major risks highlighted.")
                    with cols[1]: # Plan
                         st.markdown("**Recommended Plan:**"); plan = structured_output.get('recommended_plan', {})
                         for section in ["investigations","therapeutics","consultations","patient_education"]: st.markdown(f"_{section.replace('_',' ').capitalize()}:_"); items = plan.get(section); [st.markdown(f"- {item}") for item in items] if items and isinstance(items, list) else (st.markdown(f"- {items}") if items else st.markdown("_None_")); st.markdown("")
                    st.markdown("**Rationale & Guideline Check:**"); st.markdown(f"> {structured_output.get('rationale_summary', 'N/A')}")
                    interaction_summary = structured_output.get("interaction_check_summary", "")
                    if interaction_summary: st.markdown("**Interaction Check Summary:**"); st.markdown(f"> {interaction_summary}")
                    st.divider()
                if getattr(msg, 'tool_calls', None):
                     with st.expander("🛠️ AI requested actions", expanded=False): # Tool call display logic...
                        for tc in msg.tool_calls: try: st.code(f"Action: {tc.get('name', 'Unknown')}\nArgs: {json.dumps(tc.get('args', {}), indent=2)}", language="json")
                        except Exception as display_e: st.error(f"Could not display tool call: {display_e}"); st.code(str(tc))
        elif isinstance(msg, ToolMessage):
            tool_name_display = getattr(msg, 'name', 'tool_execution')
            with st.chat_message(tool_name_display, avatar="🛠️"): # No key
                try: # Tool message display logic...
                    tool_data = json.loads(msg.content); status = tool_data.get("status", "info"); message = tool_data.get("message", msg.content); details = tool_data.get("details"); warnings = tool_data.get("warnings")
                    if status == "success" or status == "clear" or status == "flagged": st.success(f"{message}", icon="✅" if status != "flagged" else "🚨")
                    elif status == "warning": st.warning(f"{message}", icon="⚠️");
                    if warnings and isinstance(warnings, list): st.caption("Details:"); [st.caption(f"- {warn}") for warn in warnings]
                    else: st.error(f"{message}", icon="❌")
                    if details: st.caption(f"Details: {details}")
                except json.JSONDecodeError: st.info(f"{msg.content}")
                except Exception as e: st.error(f"Error displaying tool message: {e}", icon="❌"); st.caption(f"Raw content: {msg.content}")

    # --- Chat Input Logic ---
    if prompt := st.chat_input("Your message or follow-up query..."):
        if not st.session_state.patient_data: st.warning("Please load patient data first."); st.stop()
        user_message = HumanMessage(content=prompt); st.session_state.messages.append(user_message)
        with st.chat_message("user"): st.markdown(prompt) # Display user msg immediately
        current_state = AgentState(messages=st.session_state.messages, patient_data=st.session_state.patient_data)
        with st.spinner("SynapseAI is thinking..."):
            try:
                final_state = st.session_state.graph_app.invoke(current_state, {"recursion_limit": 15})
                st.session_state.messages = final_state['messages'] # Update state with results
            except Exception as e: print(f"CRITICAL ERROR: {e}"); traceback.print_exc(); st.error(f"Error: {e}")
        st.rerun() # Refresh display

    # Disclaimer
    st.markdown("---"); st.warning("**Disclaimer:** SynapseAI is for demonstration...")

if __name__ == "__main__":
    main()