app.py

import os
import json
import time
from datetime import datetime
from typing import List, Dict, Any, Optional
from pydantic import BaseModel, Field, EmailStr, validator
from fastapi import FastAPI, HTTPException, Query, Depends, Request
from fastapi.responses import JSONResponse, Response
from fastapi.middleware.cors import CORSMiddleware
from fastapi.openapi.utils import get_openapi
import httpx
from dotenv import load_dotenv

# LangChain and OpenAI imports
try:
    from langchain_openai import ChatOpenAI
    from langchain.prompts import ChatPromptTemplate
    LANGCHAIN_AVAILABLE = True
except ImportError:
    LANGCHAIN_AVAILABLE = False
    print("Warning: LangChain not available. Install with: pip install langchain langchain-openai")

load_dotenv()

# Configuration
SMARTLEAD_API_KEY = os.getenv("SMARTLEAD_API_KEY")
SMARTLEAD_BASE_URL = "https://server.smartlead.ai/api/v1"

# Initialize FastAPI app
app = FastAPI(
    title="Smartlead API - Complete Integration",
    version="2.0.0",
    description="Comprehensive FastAPI wrapper for Smartlead email automation platform",
    docs_url="/docs",
    redoc_url="/redoc"
)

# Add CORS middleware
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

# ============================================================================
# DATA MODELS
# ============================================================================

class CreateCampaignRequest(BaseModel):
    name: str = Field(..., description="Campaign name")
    client_id: Optional[int] = Field(None, description="Client ID (leave null if no client)")

class CampaignScheduleRequest(BaseModel):
    timezone: str = Field(..., description="Timezone for the campaign schedule (e.g., 'America/Los_Angeles')")
    days_of_the_week: List[int] = Field(..., description="Days of the week for scheduling [0=Sunday, 1=Monday, 2=Tuesday, 3=Wednesday, 4=Thursday, 5=Friday, 6=Saturday]")
    start_hour: str = Field(..., description="Start hour for sending emails in HH:MM format (e.g., '09:00')")
    end_hour: str = Field(..., description="End hour for sending emails in HH:MM format (e.g., '18:00')")
    min_time_btw_emails: int = Field(..., description="Minimum time in minutes between sending emails")
    max_new_leads_per_day: int = Field(..., description="Maximum number of new leads to process per day")
    schedule_start_time: str = Field(..., description="Schedule start time in ISO 8601 format (e.g., '2023-04-25T07:29:25.978Z')")

class CampaignSettingsRequest(BaseModel):
    track_settings: List[str] = Field(..., description="Tracking settings array (allowed values: DONT_TRACK_EMAIL_OPEN, DONT_TRACK_LINK_CLICK, DONT_TRACK_REPLY_TO_AN_EMAIL)")
    stop_lead_settings: str = Field(..., description="Settings for stopping leads (allowed values: CLICK_ON_A_LINK, OPEN_AN_EMAIL)")
    unsubscribe_text: str = Field(..., description="Text for the unsubscribe link")
    send_as_plain_text: bool = Field(..., description="Whether emails should be sent as plain text")
    follow_up_percentage: int = Field(ge=0, le=100, description="Follow-up percentage (max 100, min 0)")
    client_id: Optional[int] = Field(None, description="Client ID (leave as null if not needed)")
    enable_ai_esp_matching: bool = Field(False, description="Enable AI ESP matching (by default is false)")

class LeadInput(BaseModel):
    first_name: Optional[str] = Field(None, description="Lead's first name")
    last_name: Optional[str] = Field(None, description="Lead's last name")
    email: str = Field(..., description="Lead's email address")
    phone_number: Optional[str] = Field(None, description="Lead's phone number")
    company_name: Optional[str] = Field(None, description="Lead's company name")
    website: Optional[str] = Field(None, description="Lead's website")
    location: Optional[str] = Field(None, description="Lead's location")
    custom_fields: Optional[Dict[str, str]] = Field(None, description="Custom fields as key-value pairs")
    linkedin_profile: Optional[str] = Field(None, description="Lead's LinkedIn profile URL")
    company_url: Optional[str] = Field(None, description="Company website URL")

class LeadSettings(BaseModel):
    ignore_global_block_list: bool = Field(True, description="Ignore leads if they are in the global block list")
    ignore_unsubscribe_list: bool = Field(True, description="Ignore leads if they are in the unsubscribe list")
    ignore_duplicate_leads_in_other_campaign: bool = Field(False, description="Allow leads to be added even if they are duplicates in other campaigns")

class AddLeadsRequest(BaseModel):
    lead_list: List[LeadInput] = Field(..., max_items=100, description="List of leads to add (maximum 100 leads)")
    settings: Optional[LeadSettings] = Field(None, description="Settings for lead processing")

class AddLeadsResponse(BaseModel):
    ok: bool = Field(..., description="Indicates if the operation was successful")
    upload_count: int = Field(..., description="Number of leads successfully uploaded")
    total_leads: int = Field(..., description="Total number of leads attempted to upload")
    already_added_to_campaign: int = Field(..., description="Number of leads already present in the campaign")
    duplicate_count: int = Field(..., description="Number of duplicate emails found")
    invalid_email_count: int = Field(..., description="Number of leads with invalid email format")
    unsubscribed_leads: Any = Field(..., description="Number of leads that had previously unsubscribed (can be int or empty list)")

class SeqDelayDetails(BaseModel):
    delay_in_days: int = Field(..., description="Delay in days before sending this sequence")

class SeqVariant(BaseModel):
    subject: str = Field(..., description="Email subject line")
    email_body: str = Field(..., description="Email body content (HTML format)")
    variant_label: str = Field(..., description="Variant label (A, B, C, etc.)")
    id: Optional[int] = Field(None, description="Variant ID (only for updating, not for creating)")

class CampaignSequence(BaseModel):
    id: Optional[int] = Field(None, description="Sequence ID (only for updating, not for creating)")
    seq_number: int = Field(..., description="Sequence number (1, 2, 3, etc.)")
    seq_delay_details: SeqDelayDetails = Field(..., description="Delay details for this sequence")
    seq_variants: Optional[List[SeqVariant]] = Field(None, description="Email variants for A/B testing")
    subject: Optional[str] = Field("", description="Subject line (blank for follow-up in same thread)")
    email_body: Optional[str] = Field(None, description="Email body content (HTML format)")

class SaveSequencesRequest(BaseModel):
    sequences: List[CampaignSequence] = Field(..., description="List of campaign sequences")

class GenerateSequencesRequest(BaseModel):
    job_description: str = Field(..., description="Job description to generate sequences for")

class Campaign(BaseModel):
    id: int = Field(..., description="The unique ID of the campaign")
    user_id: int = Field(..., description="The ID of the user who owns the campaign")
    created_at: datetime = Field(..., description="Timestamp of when the campaign was created")
    updated_at: datetime = Field(..., description="Timestamp of the last update to the campaign")
    status: str = Field(..., description="Current status of the campaign (DRAFTED, ACTIVE, COMPLETED, STOPPED, PAUSED)")
    name: str = Field(..., description="The name of the campaign")
    track_settings: str = Field(..., description="Tracking settings string (e.g., 'DONT_REPLY_TO_AN_EMAIL')")
    scheduler_cron_value: Optional[str] = Field(None, description="Scheduling details as JSON string")
    min_time_btwn_emails: int = Field(..., description="Minimum time between emails in minutes")
    max_leads_per_day: int = Field(..., description="Maximum number of leads to process per day")
    stop_lead_settings: str = Field(..., description="Settings for stopping leads (REPLY_TO_AN_EMAIL, CLICK_ON_ANY_LINK, etc.)")
    enable_ai_esp_matching: bool = Field(..., description="Indicates if AI ESP matching is enabled")
    send_as_plain_text: bool = Field(..., description="Indicates if emails for this campaign are sent as plain text")
    follow_up_percentage: str = Field(..., description="The percentage of follow-up emails allocated (e.g., '40%')")
    unsubscribe_text: Optional[str] = Field(None, description="The text used for the unsubscribe link")
    parent_campaign_id: Optional[int] = Field(None, description="Parent campaign ID if this is a child campaign")
    client_id: Optional[int] = Field(None, description="The ID of the client associated with the campaign (null if not attached to a client)")
    
    @validator('scheduler_cron_value', pre=True)
    def parse_scheduler_cron_value(cls, v):
        """Parse scheduler_cron_value from JSON string to dict if needed"""
        if isinstance(v, str) and v:
            try:
                import json
                return json.loads(v)
            except json.JSONDecodeError:
                return v
        return v
    
    @validator('follow_up_percentage', pre=True)
    def parse_follow_up_percentage(cls, v):
        """Ensure follow_up_percentage is returned as string with % sign"""
        if isinstance(v, int):
            return f"{v}%"
        return v

class Lead(BaseModel):
    id: int
    email: EmailStr
    first_name: Optional[str]
    last_name: Optional[str]
    company: Optional[str]
    position: Optional[str]
    phone_number: Optional[str]
    linkedin_url: Optional[str]
    status: Optional[str]

# Additional models for new endpoints
class LeadCategoryUpdateRequest(BaseModel):
    category_id: int = Field(..., description="Category ID to assign to the lead")
    pause_lead: bool = Field(False, description="Whether to pause the lead after category update")

class CampaignStatusUpdateRequest(BaseModel):
    status: str = Field(..., description="New campaign status (PAUSED, STOPPED, START)")

class ResumeLeadRequest(BaseModel):
    resume_lead_with_delay_days: Optional[int] = Field(None, description="Delay in days before resuming (defaults to 0)")

class DomainBlockListRequest(BaseModel):
    domain_block_list: List[str] = Field(..., description="List of domains/emails to block")
    client_id: Optional[int] = Field(None, description="Client ID if blocking is client-specific")

class WebhookRequest(BaseModel):
    id: Optional[int] = Field(None, description="Webhook ID (null for creating new)")
    name: str = Field(..., description="Webhook name")
    webhook_url: str = Field(..., description="Webhook URL")
    event_types: List[str] = Field(..., description="List of event types to listen for")
    categories: Optional[List[str]] = Field(None, description="List of categories to filter by")

class WebhookDeleteRequest(BaseModel):
    id: int = Field(..., description="Webhook ID to delete")

class ClientRequest(BaseModel):
    name: str = Field(..., description="Client name")
    email: str = Field(..., description="Client email")
    permission: List[str] = Field(..., description="List of permissions")
    logo: Optional[str] = Field(None, description="Client logo text")
    logo_url: Optional[str] = Field(None, description="Client logo URL")
    password: str = Field(..., description="Client password")

class MessageHistoryRequest(BaseModel):
    email_stats_id: str = Field(..., description="Email stats ID for the specific email")
    email_body: str = Field(..., description="Reply message email body")
    reply_message_id: str = Field(..., description="Message ID to reply to")
    reply_email_time: str = Field(..., description="Time of the message being replied to")
    reply_email_body: str = Field(..., description="Body of the message being replied to")
    cc: Optional[str] = Field(None, description="CC recipients")
    bcc: Optional[str] = Field(None, description="BCC recipients")
    add_signature: bool = Field(True, description="Whether to add signature")

# ============================================================================
# HELPER FUNCTIONS
# ============================================================================

def _get_smartlead_url(endpoint: str) -> str:
    return f"{SMARTLEAD_BASE_URL}/{endpoint.lstrip('/')}"

async def call_smartlead_api(method: str, endpoint: str, data: Any = None, params: Dict[str, Any] = None) -> Any:
    if SMARTLEAD_API_KEY == "your-api-key-here":
        raise HTTPException(status_code=400, detail="Smartlead API key not configured")
    if params is None:
        params = {}
    params['api_key'] = SMARTLEAD_API_KEY
    url = _get_smartlead_url(endpoint)
    
    try:
        async with httpx.AsyncClient(timeout=30.0) as client:
            if method.upper() in ("GET", "DELETE"):
                resp = await client.request(method, url, params=params)
            else:
                resp = await client.request(method, url, params=params, json=data)
        
        if resp.status_code >= 400:
            # Try to parse error response as JSON for better error handling
            try:
                error_data = resp.json()
                error_message = error_data.get('message', error_data.get('error', 'Unknown error'))
                error_detail = error_data.get('detail', error_data.get('description', ''))
                
                raise HTTPException(
                    status_code=resp.status_code,
                    detail={
                        "error": True,
                        "message": error_message,
                        "detail": error_detail,
                        "endpoint": endpoint,
                        "method": method,
                        "status_code": resp.status_code
                    }
                )
            except (ValueError, KeyError):
                # Fallback to raw text if JSON parsing fails
                raise HTTPException(
                    status_code=resp.status_code,
                    detail={
                        "error": True,
                        "message": "API request failed",
                        "detail": resp.text,
                        "endpoint": endpoint,
                        "method": method,
                        "status_code": resp.status_code
                    }
                )
        
        return resp.json()
        
    except httpx.TimeoutException:
        raise HTTPException(
            status_code=408,
            detail={
                "error": True,
                "message": "Request timeout",
                "detail": "The request to Smartlead API timed out",
                "endpoint": endpoint,
                "method": method
            }
        )
    except httpx.RequestError as e:
        raise HTTPException(
            status_code=503,
            detail={
                "error": True,
                "message": "Service unavailable",
                "detail": f"Failed to connect to Smartlead API: {str(e)}",
                "endpoint": endpoint,
                "method": method
            }
        )

# ============================================================================
# CAMPAIGN ENDPOINTS
# ============================================================================

@app.post("/campaigns/create", response_model=Dict[str, Any], tags=["Campaigns"])
async def create_campaign(campaign: CreateCampaignRequest):
    """Create a new campaign in Smartlead"""
    return await call_smartlead_api("POST", "campaigns/create", data=campaign.dict())

@app.get("/campaigns", response_model=Dict[str, Any], tags=["Campaigns"])
async def list_campaigns():
    """Fetch all campaigns from Smartlead API"""
    campaigns = await call_smartlead_api("GET", "campaigns")
    return {"campaigns": campaigns, "total": len(campaigns), "source": "smartlead"}

@app.get("/campaigns/{campaign_id}", response_model=Campaign, tags=["Campaigns"])
async def get_campaign(campaign_id: int):
    """Get Campaign By Id"""
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}")

@app.post("/campaigns/{campaign_id}/settings", response_model=Dict[str, Any], tags=["Campaigns"])
async def update_campaign_settings(campaign_id: int, settings: CampaignSettingsRequest):
    """Update Campaign General Settings"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/settings", data=settings.dict())

@app.post("/campaigns/{campaign_id}/schedule", response_model=Dict[str, Any], tags=["Campaigns"])
async def schedule_campaign(campaign_id: int, schedule: CampaignScheduleRequest):
    """Update Campaign Schedule"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/schedule", data=schedule.dict())

@app.delete("/campaigns/{campaign_id}", response_model=Dict[str, Any], tags=["Campaigns"])
async def delete_campaign(campaign_id: int):
    """Delete Campaign"""
    return await call_smartlead_api("DELETE", f"campaigns/{campaign_id}")

@app.post("/campaigns/{campaign_id}/status", response_model=Dict[str, Any], tags=["Campaigns"])
async def patch_campaign_status(campaign_id: int, request: CampaignStatusUpdateRequest):
    """Patch campaign status"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/status", data=request.dict())

@app.get("/campaigns/{campaign_id}/analytics", response_model=Any, tags=["Analytics"])
async def campaign_analytics(campaign_id: int):
    """Fetch analytics for a campaign"""
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/analytics")

@app.get("/campaigns/{campaign_id}/statistics", response_model=Dict[str, Any], tags=["Analytics"])
async def fetch_campaign_statistics_by_campaign_id(
    campaign_id: int, 
    offset: int = 0, 
    limit: int = 100,
    email_sequence_number: Optional[int] = None,
    email_status: Optional[str] = None
):
    """Fetch Campaign Statistics By Campaign Id"""
    params = {"offset": offset, "limit": limit}
    if email_sequence_number:
        params["email_sequence_number"] = email_sequence_number
    if email_status:
        params["email_status"] = email_status
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/statistics", params=params)

@app.get("/campaigns/{campaign_id}/analytics-by-date", response_model=Dict[str, Any], tags=["Analytics"])
async def fetch_campaign_statistics_by_date_range(
    campaign_id: int, 
    start_date: str, 
    end_date: str
):
    """Fetch Campaign Statistics By Campaign Id And Date Range"""
    params = {"start_date": start_date, "end_date": end_date}
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/analytics-by-date", params=params)

# ============================================================================
# LEAD MANAGEMENT ENDPOINTS
# ============================================================================

@app.get("/campaigns/{campaign_id}/leads", response_model=Dict[str, Any], tags=["Leads"])
async def get_campaign_leads(campaign_id: int, offset: int = 0, limit: int = 100):
    """List all leads by campaign id"""
    params = {"offset": offset, "limit": limit}
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/leads", params=params)

@app.post("/campaigns/{campaign_id}/leads", response_model=Dict[str, Any], tags=["Leads"])
async def add_leads_to_campaign(campaign_id: int, request: AddLeadsRequest):
    """Add leads to a campaign by ID"""
    request_data = request.dict()
    
    # Clean up the data - remove None values and empty strings
    for lead in request_data.get("lead_list", []):
        lead_cleaned = {k: v for k, v in lead.items() if v is not None and v != ""}
        
        if "custom_fields" in lead_cleaned:
            custom_fields = lead_cleaned["custom_fields"]
            if custom_fields:
                custom_fields_cleaned = {k: v for k, v in custom_fields.items() if v is not None and v != ""}
                if custom_fields_cleaned:
                    lead_cleaned["custom_fields"] = custom_fields_cleaned
                else:
                    lead_cleaned.pop("custom_fields", None)
            else:
                lead_cleaned.pop("custom_fields", None)
        
        lead.clear()
        lead.update(lead_cleaned)
    
    request_data["lead_list"] = [lead for lead in request_data["lead_list"] if lead]
    
    if not request_data["lead_list"]:
        raise HTTPException(status_code=400, detail="No valid leads to add. Please provide at least one lead with an email address.")
    
    if "settings" not in request_data or request_data["settings"] is None:
        request_data["settings"] = {
            "ignore_global_block_list": True,
            "ignore_unsubscribe_list": True,
            "ignore_duplicate_leads_in_other_campaign": False
        }
    
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/leads", data=request_data)

@app.post("/campaigns/{campaign_id}/leads/bulk", response_model=Dict[str, Any], tags=["Leads"])
async def add_bulk_leads(campaign_id: int, leads: List[LeadInput]):
    """Add multiple leads to a Smartlead campaign (legacy endpoint)"""
    request = AddLeadsRequest(lead_list=leads)
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/leads", data=request.dict())

@app.post("/campaigns/{campaign_id}/leads/{lead_id}/resume", response_model=Dict[str, Any], tags=["Leads"])
async def resume_lead_by_campaign_id(campaign_id: int, lead_id: int, request: ResumeLeadRequest):
    """Resume Lead By Campaign ID"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/leads/{lead_id}/resume", data=request.dict())

@app.post("/campaigns/{campaign_id}/leads/{lead_id}/pause", response_model=Dict[str, Any], tags=["Leads"])
async def pause_lead_by_campaign_id(campaign_id: int, lead_id: int):
    """Pause Lead By Campaign ID"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/leads/{lead_id}/pause")

@app.delete("/campaigns/{campaign_id}/leads/{lead_id}", response_model=Dict[str, Any], tags=["Leads"])
async def delete_lead_by_campaign_id(campaign_id: int, lead_id: int):
    """Delete Lead By Campaign ID"""
    return await call_smartlead_api("DELETE", f"campaigns/{campaign_id}/leads/{lead_id}")

@app.post("/campaigns/{campaign_id}/leads/{lead_id}/unsubscribe", response_model=Dict[str, Any], tags=["Leads"])
async def unsubscribe_lead_from_campaign(campaign_id: int, lead_id: int):
    """Unsubscribe/Pause Lead From Campaign"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/leads/{lead_id}/unsubscribe")

@app.post("/leads/{lead_id}/unsubscribe", response_model=Dict[str, Any], tags=["Leads"])
async def unsubscribe_lead_from_all_campaigns(lead_id: int):
    """Unsubscribe Lead From All Campaigns"""
    return await call_smartlead_api("POST", f"leads/{lead_id}/unsubscribe")

@app.post("/leads/{lead_id}", response_model=Dict[str, Any], tags=["Leads"])
async def update_lead(lead_id: int, lead_data: Dict[str, Any]):
    """Update lead using the Lead ID"""
    return await call_smartlead_api("POST", f"leads/{lead_id}", data=lead_data)

@app.post("/campaigns/{campaign_id}/leads/{lead_id}/category", response_model=Dict[str, Any], tags=["Leads"])
async def update_lead_category_by_campaign(campaign_id: int, lead_id: int, request: LeadCategoryUpdateRequest):
    """Update a lead's category based on their campaign"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/leads/{lead_id}/category", data=request.dict())

@app.post("/leads/add-domain-block-list", response_model=Dict[str, Any], tags=["Leads"])
async def add_domain_to_global_block_list(request: DomainBlockListRequest):
    """Add Lead/Domain to Global Block List"""
    return await call_smartlead_api("POST", "leads/add-domain-block-list", data=request.dict())

@app.get("/leads/fetch-categories", response_model=List[Dict[str, Any]], tags=["Leads"])
async def fetch_lead_categories():
    """Fetch lead categories"""
    return await call_smartlead_api("GET", "leads/fetch-categories")

@app.get("/leads", response_model=Dict[str, Any], tags=["Leads"])
async def fetch_lead_by_email_address(email: str):
    """Fetch lead by email address"""
    return await call_smartlead_api("GET", "leads", params={"email": email})

@app.get("/leads/{lead_id}/campaigns", response_model=List[Dict[str, Any]], tags=["Leads"])
async def campaigns_for_lead(lead_id: int):
    """Fetch all campaigns that a lead belongs to"""
    return await call_smartlead_api("GET", f"leads/{lead_id}/campaigns")

@app.get("/campaigns/{campaign_id}/leads/check", response_model=Dict[str, Any], tags=["Leads"])
async def check_lead_in_campaign(campaign_id: int, email: str):
    """Check if a lead exists in a campaign using efficient indexed lookups"""
    try:
        # Step 1: Get the global lead_id for the email address
        lead_response = await call_smartlead_api("GET", "leads", params={"email": email})
        
        if not lead_response or "id" not in lead_response:
            return {
                "exists": False,
                "message": "Lead not found",
                "email": email,
                "campaign_id": campaign_id
            }
        
        lead_id = lead_response["id"]
        
        # Step 2: Get all campaigns for this lead
        campaigns_response = await call_smartlead_api("GET", f"leads/{lead_id}/campaigns")
        
        if not campaigns_response:
            return {
                "exists": False,
                "message": "No campaigns found for lead",
                "email": email,
                "campaign_id": campaign_id,
                "lead_id": lead_id
            }
        
        # Step 3: Check if the target campaign_id exists in the lead's campaigns
        campaign_exists = any(campaign.get("id") == campaign_id for campaign in campaigns_response)
        
        return {
            "exists": campaign_exists,
            "message": "Lead found in campaign" if campaign_exists else "Lead not found in campaign",
            "email": email,
            "campaign_id": campaign_id,
            "lead_id": lead_id,
            "total_campaigns_for_lead": len(campaigns_response)
        }
        
    except HTTPException as e:
        if e.status_code == 404:
            return {
                "exists": False,
                "message": "Lead not found",
                "email": email,
                "campaign_id": campaign_id
            }
        raise e
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error checking lead in campaign: {str(e)}")

@app.get("/campaigns/{campaign_id}/leads-export", tags=["Leads"])
async def export_data_from_campaign(campaign_id: int):
    """Export data from a campaign as CSV"""
    if SMARTLEAD_API_KEY == "your-api-key-here":
        raise HTTPException(status_code=400, detail="Smartlead API key not configured")
    
    url = _get_smartlead_url(f"campaigns/{campaign_id}/leads-export")
    params = {"api_key": SMARTLEAD_API_KEY}
    
    try:
        async with httpx.AsyncClient(timeout=30.0) as client:
            resp = await client.get(url, params=params)
        
        if resp.status_code >= 400:
            # Try to parse error response as JSON for better error handling
            try:
                error_data = resp.json()
                error_message = error_data.get('message', error_data.get('error', 'Unknown error'))
                error_detail = error_data.get('detail', error_data.get('description', ''))
                
                raise HTTPException(
                    status_code=resp.status_code,
                    detail={
                        "error": True,
                        "message": error_message,
                        "detail": error_detail,
                        "endpoint": f"campaigns/{campaign_id}/leads-export",
                        "method": "GET",
                        "status_code": resp.status_code
                    }
                )
            except (ValueError, KeyError):
                # Fallback to raw text if JSON parsing fails
                raise HTTPException(
                    status_code=resp.status_code,
                    detail={
                        "error": True,
                        "message": "API request failed",
                        "detail": resp.text,
                        "endpoint": f"campaigns/{campaign_id}/leads-export",
                        "method": "GET",
                        "status_code": resp.status_code
                    }
                )
        
        # Return CSV data with proper headers
        return Response(
            content=resp.text,
            media_type="text/csv",
            headers={
                "Content-Disposition": f"attachment; filename=campaign_{campaign_id}_leads.csv"
            }
        )
        
    except httpx.TimeoutException:
        raise HTTPException(
            status_code=408,
            detail={
                "error": True,
                "message": "Request timeout",
                "detail": "The request to Smartlead API timed out",
                "endpoint": f"campaigns/{campaign_id}/leads-export",
                "method": "GET"
            }
        )
    except httpx.RequestError as e:
        raise HTTPException(
            status_code=503,
            detail={
                "error": True,
                "message": "Service unavailable",
                "detail": f"Failed to connect to Smartlead API: {str(e)}",
                "endpoint": f"campaigns/{campaign_id}/leads-export",
                "method": "GET"
            }
        )

# ============================================================================
# SEQUENCE ENDPOINTS
# ============================================================================

@app.get("/campaigns/{campaign_id}/sequences", response_model=Any, tags=["Sequences"])
async def get_campaign_sequences(campaign_id: int):
    """Fetch email sequences for a campaign"""
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/sequences")

@app.post("/campaigns/{campaign_id}/sequences", response_model=Dict[str, Any], tags=["Sequences"])
async def save_campaign_sequences(campaign_id: int, request: SaveSequencesRequest):
    """Save Campaign Sequence"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/sequences", data=request.dict())

@app.post("/campaigns/{campaign_id}/sequences/generate", response_model=Dict[str, Any], tags=["Sequences"])
async def generate_campaign_sequences(campaign_id: int, request: GenerateSequencesRequest):
    """Generate Campaign Sequences using LLM"""
    job_description = request.job_description
    generated_sequences = await generate_sequences_with_llm(job_description)
    save_request = SaveSequencesRequest(sequences=generated_sequences)
    result = await call_smartlead_api("POST", f"campaigns/{campaign_id}/sequences", data=save_request.dict())
    
    return {
        "ok": True,
        "message": "Sequences generated and saved successfully",
        "generated_sequences": [seq.dict() for seq in generated_sequences],
        "save_result": result
    }

# ============================================================================
# WEBHOOK ENDPOINTS
# ============================================================================

@app.get("/campaigns/{campaign_id}/webhooks", response_model=List[Dict[str, Any]], tags=["Webhooks"])
async def fetch_webhooks_by_campaign_id(campaign_id: int):
    """Fetch Webhooks By Campaign ID"""
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/webhooks")

@app.post("/campaigns/{campaign_id}/webhooks", response_model=Dict[str, Any], tags=["Webhooks"])
async def add_update_campaign_webhook(campaign_id: int, request: WebhookRequest):
    """Add / Update Campaign Webhook"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/webhooks", data=request.dict())

@app.delete("/campaigns/{campaign_id}/webhooks", response_model=Dict[str, Any], tags=["Webhooks"])
async def delete_campaign_webhook(campaign_id: int, request: WebhookDeleteRequest):
    """Delete Campaign Webhook"""
    return await call_smartlead_api("DELETE", f"campaigns/{campaign_id}/webhooks", data=request.dict())

# ============================================================================
# CLIENT MANAGEMENT ENDPOINTS
# ============================================================================

@app.post("/client/save", response_model=Dict[str, Any], tags=["Clients"])
async def add_client_to_system(request: ClientRequest):
    """Add Client To System (Whitelabel or not)"""
    return await call_smartlead_api("POST", "client/save", data=request.dict())

@app.get("/client", response_model=List[Dict[str, Any]], tags=["Clients"])
async def fetch_all_clients():
    """Fetch all clients"""
    return await call_smartlead_api("GET", "client")

# ============================================================================
# MESSAGE HISTORY AND REPLY ENDPOINTS
# ============================================================================

@app.get("/campaigns/{campaign_id}/leads/{lead_id}/message-history", response_model=Dict[str, Any], tags=["Messages"])
async def fetch_lead_message_history_based_on_campaign(campaign_id: int, lead_id: int):
    """Fetch Lead Message History Based On Campaign"""
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/leads/{lead_id}/message-history")

@app.post("/campaigns/{campaign_id}/reply-email-thread", response_model=Dict[str, Any], tags=["Messages"])
async def reply_to_lead_from_master_inbox(campaign_id: int, request: MessageHistoryRequest):
    """Reply To Lead From Master Inbox via API"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/reply-email-thread", data=request.dict())

# ============================================================================
# EMAIL ACCOUNT ENDPOINTS
# ============================================================================

@app.get("/email-accounts", response_model=Dict[str, Any], tags=["Email Accounts"])
async def list_email_accounts(offset: int = 0, limit: int = 100):
    """List all email accounts with optional pagination"""
    params = {"offset": offset, "limit": limit}
    return await call_smartlead_api("GET", "email-accounts", params=params)

@app.post("/email-accounts/save", response_model=Any, tags=["Email Accounts"])
async def save_email_account(account: Dict[str, Any]):
    """Create an Email Account"""
    return await call_smartlead_api("POST", "email-accounts/save", data=account)

@app.get("/email-accounts/{account_id}", response_model=Any, tags=["Email Accounts"])
async def get_email_account(account_id: int):
    """Fetch Email Account By ID"""
    return await call_smartlead_api("GET", f"email-accounts/{account_id}")

@app.post("/email-accounts/{account_id}", response_model=Any, tags=["Email Accounts"])
async def update_email_account(account_id: int, payload: Dict[str, Any]):
    """Update Email Account"""
    return await call_smartlead_api("POST", f"email-accounts/{account_id}", data=payload)

@app.post("/email-accounts/{account_id}/warmup", response_model=Any, tags=["Email Accounts"])
async def set_warmup(account_id: int, payload: Dict[str, Any]):
    """Add/Update Warmup To Email Account"""
    return await call_smartlead_api("POST", f"email-accounts/{account_id}/warmup", data=payload)

@app.get("/email-accounts/{account_id}/warmup-stats", response_model=Any, tags=["Email Accounts"])
async def get_warmup_stats(account_id: int):
    """Fetch Warmup Stats By Email Account ID"""
    return await call_smartlead_api("GET", f"email-accounts/{account_id}/warmup-stats")

@app.get("/campaigns/{campaign_id}/email-accounts", response_model=Any, tags=["Email Accounts"])
async def list_campaign_email_accounts(campaign_id: int):
    """List all email accounts per campaign"""
    return await call_smartlead_api("GET", f"campaigns/{campaign_id}/email-accounts")

@app.post("/campaigns/{campaign_id}/email-accounts", response_model=Any, tags=["Email Accounts"])
async def add_campaign_email_accounts(campaign_id: int, payload: Dict[str, Any]):
    """Add Email Account To A Campaign"""
    return await call_smartlead_api("POST", f"campaigns/{campaign_id}/email-accounts", data=payload)

@app.delete("/campaigns/{campaign_id}/email-accounts", response_model=Any, tags=["Email Accounts"])
async def remove_campaign_email_accounts(campaign_id: int, payload: Dict[str, Any]):
    """Remove Email Account From A Campaign"""
    return await call_smartlead_api("DELETE", f"campaigns/{campaign_id}/email-accounts", data=payload)

@app.post("/email-accounts/reconnect-failed-email-accounts", response_model=Dict[str, Any], tags=["Email Accounts"])
async def reconnect_failed_email_accounts():
    """Reconnect failed email accounts"""
    return await call_smartlead_api("POST", "email-accounts/reconnect-failed-email-accounts")

# ============================================================================
# UTILITY ENDPOINTS
# ============================================================================

@app.get("/health", response_model=Dict[str, Any], tags=["Utilities"])
async def health_check():
    """Health check endpoint to verify API connectivity"""
    try:
        campaigns = await call_smartlead_api("GET", "campaigns")
        return {
            "status": "healthy",
            "message": "Smartlead API is accessible",
            "campaigns_count": len(campaigns) if isinstance(campaigns, list) else 0,
            "timestamp": datetime.now().isoformat()
        }
    except Exception as e:
        return {
            "status": "unhealthy",
            "message": f"Smartlead API connection failed: {str(e)}",
            "timestamp": datetime.now().isoformat()
        }

@app.get("/api-info", response_model=Dict[str, Any], tags=["Utilities"])
async def api_info():
    """Get information about the API and available endpoints"""
    return {
        "name": "Smartlead API - Complete Integration",
        "version": "2.0.0",
        "description": "Comprehensive FastAPI wrapper for Smartlead email automation platform",
        "base_url": SMARTLEAD_BASE_URL,
        "available_endpoints": [
            "Campaign Management",
            "Lead Management", 
            "Sequence Management",
            "Webhook Management",
            "Client Management",
            "Message History & Reply",
            "Analytics",
            "Email Account Management"
        ],
        "documentation": "Based on Smartlead API documentation",
        "timestamp": datetime.now().isoformat()
    }

# ============================================================================
# AI SEQUENCE GENERATION FUNCTIONS
# ============================================================================

async def generate_sequences_with_llm(job_description: str) -> List[CampaignSequence]:
    """Generate email sequences using LangChain and OpenAI based on job description"""
    
    if not LANGCHAIN_AVAILABLE:
        return await generate_template_sequences(job_description)
    
    try:
        openai_api_key = os.getenv("OPENAI_API_KEY")
        if not openai_api_key:
            print("Warning: OPENAI_API_KEY not set. Using template sequences.")
            return await generate_template_sequences(job_description)
        
        llm = ChatOpenAI(
            model="gpt-4",
            temperature=0.7,
            openai_api_key=openai_api_key
        )
        
        system_prompt = """You are an expert email sequence generator for recruitment campaigns. 
        
        Generate ONLY the subject lines and email body content for 3 professional email sequences.
        
        Email Sequence Structure:
        1. INTRODUCTION (Day 1): Ask for consent and interest in the role
        2. OUTREACH (Day 3): Provide detailed job information  
        3. FOLLOW-UP (Day 5): Follow up on updates and next steps
        
        Requirements:
        - First sequence needs 2 A/B testing variants (A and B)
        - Second and third sequences are follow-ups (no subject line needed)
        - All emails should be HTML formatted with proper <br> tags
        - Professional but friendly tone
        - Include clear call-to-actions
        - Focus on building consent and trust
        
        Respond with ONLY a JSON object containing the email content:
        {
            "sequence1_variant_a": {
                "subject": "Subject line for variant A",
                "body": "HTML formatted email body for variant A"
            },
            "sequence1_variant_b": {
                "subject": "Subject line for variant B", 
                "body": "HTML formatted email body for variant B"
            },
            "sequence2": {
                "body": "HTML formatted email body for outreach"
            },
            "sequence3": {
                "body": "HTML formatted email body for follow-up"
            }
        }
        
        IMPORTANT: Respond with ONLY valid JSON. No additional text."""
        
        prompt_template = ChatPromptTemplate.from_messages([
            ("system", system_prompt),
            ("human", "Generate email content for this job description: {job_description}")
        ])
        
        messages = prompt_template.format_messages(job_description=job_description)
        response = await llm.ainvoke(messages)
        
        try:
            content = response.content.strip()
            
            if content.startswith("```json"):
                content = content[7:]
            if content.endswith("```"):
                content = content[:-3]
            
            content = content.strip()
            parsed_data = json.loads(content)
            sequences = create_sequences_from_content(parsed_data, job_description)
            return sequences
            
        except Exception as parse_error:
            print(f"JSON parsing failed: {parse_error}")
            return await generate_template_sequences(job_description)
        
    except Exception as e:
        print(f"Error generating sequences with LLM: {str(e)}")
        return await generate_template_sequences(job_description)

def create_sequences_from_content(content: dict, job_description: str) -> List[CampaignSequence]:
    """Create CampaignSequence objects from parsed LLM content"""
    
    sequences = []
    
    # Sequence 1: Introduction with A/B variants
    if "sequence1_variant_a" in content and "sequence1_variant_b" in content:
        variants = []
        
        if "sequence1_variant_a" in content:
            var_a = content["sequence1_variant_a"]
            variants.append(SeqVariant(
                subject=var_a.get("subject", f"Quick question about {job_description}"),
                email_body=var_a.get("body", ""),
                variant_label="A"
            ))
        
        if "sequence1_variant_b" in content:
            var_b = content["sequence1_variant_b"]
            variants.append(SeqVariant(
                subject=var_b.get("subject", f"Interested in {job_description} opportunities?"),
                email_body=var_b.get("body", ""),
                variant_label="B"
            ))
        
        sequences.append(CampaignSequence(
            seq_number=1,
            seq_delay_details=SeqDelayDetails(delay_in_days=1),
            seq_variants=variants
        ))
    
    # Sequence 2: Outreach
    if "sequence2" in content:
        seq2_body = content["sequence2"].get("body", "")
        sequences.append(CampaignSequence(
            seq_number=2,
            seq_delay_details=SeqDelayDetails(delay_in_days=3),
            subject="",
            email_body=seq2_body
        ))
    
    # Sequence 3: Follow-up
    if "sequence3" in content:
        seq3_body = content["sequence3"].get("body", "")
        sequences.append(CampaignSequence(
            seq_number=3,
            seq_delay_details=SeqDelayDetails(delay_in_days=5),
            subject="",
            email_body=seq3_body
        ))
    
    # Fill with templates if needed
    while len(sequences) < 3:
        if len(sequences) == 0:
            sequences.append(CampaignSequence(
                seq_number=1,
                seq_delay_details=SeqDelayDetails(delay_in_days=1),
                seq_variants=[
                    SeqVariant(
                        subject=f"Quick question about {job_description}",
                        email_body=f"""<p>Hi there,<br><br>
I came across your profile and noticed your experience in {job_description}. 
I'm reaching out because we have some exciting opportunities that might be a great fit for your background.<br><br>
Before I share more details, I wanted to ask: Are you currently open to exploring new opportunities in this space?<br><br>
Would you be interested in hearing more about the roles we have available?<br><br>
Best regards,<br>
[Your Name]</p>""",
                        variant_label="A"
                    ),
                    SeqVariant(
                        subject=f"Interested in {job_description} opportunities?",
                        email_body=f"""<p>Hello,<br><br>
I hope this message finds you well. I'm a recruiter specializing in {job_description} positions.<br><br>
I'd love to connect and share some opportunities that align with your expertise. 
Are you currently open to exploring new roles in this space?<br><br>
If so, I can send you specific details about the positions we have available.<br><br>
Thanks,<br>
[Your Name]</p>""",
                        variant_label="B"
                    )
                ]
            ))
        elif len(sequences) == 1:
            sequences.append(CampaignSequence(
                seq_number=2,
                seq_delay_details=SeqDelayDetails(delay_in_days=3),
                subject="",
                email_body=f"""<p>Hi,<br><br>
Thanks for your interest! Here are more details about the {job_description} opportunities:<br><br>
<strong>Role Details:</strong><br>
• [Specific responsibilities]<br>
• [Required skills and experience]<br>
• [Team and company information]<br><br>
<strong>Benefits:</strong><br>
• [Compensation and benefits]<br>
• [Growth opportunities]<br>
• [Work environment]<br><br>
Would you be interested in a quick call to discuss this role in more detail?<br><br>
Best regards,<br>
[Your Name]</p>"""
            ))
        elif len(sequences) == 2:
            sequences.append(CampaignSequence(
                seq_number=3,
                seq_delay_details=SeqDelayDetails(delay_in_days=5),
                subject="",
                email_body=f"""<p>Hi,<br><br>
Just wanted to follow up on the {job_description} opportunity I shared.<br><br>
Have you had a chance to review the information? I'd love to hear your thoughts and answer any questions.<br><br>
If you're interested, I can help schedule next steps. If not, no worries at all!<br><br>
Thanks for your time!<br>
[Your Name]</p>"""
            ))
    
    return sequences

async def generate_template_sequences(job_description: str) -> List[CampaignSequence]:
    """Generate template-based sequences as fallback"""
    
    sequences = [
        CampaignSequence(
            seq_number=1,
            seq_delay_details=SeqDelayDetails(delay_in_days=1),
            seq_variants=[
                SeqVariant(
                    subject=f"Quick question about {job_description}",
                    email_body=f"""<p>Hi there,<br><br>
I came across your profile and noticed your experience in {job_description}. 
I'm reaching out because we have some exciting opportunities that might be a great fit for your background.<br><br>
Before I share more details, I wanted to ask: Are you currently open to exploring new opportunities in this space?<br><br>
Would you be interested in hearing more about the roles we have available?<br><br>
Best regards,<br>
[Your Name]</p>""",
                    variant_label="A"
                ),
                SeqVariant(
                    subject=f"Interested in {job_description} opportunities?",
                    email_body=f"""<p>Hello,<br><br>
I hope this message finds you well. I'm a recruiter specializing in {job_description} positions.<br><br>
I'd love to connect and share some opportunities that align with your expertise. 
Are you currently open to exploring new roles in this space?<br><br>
If so, I can send you specific details about the positions we have available.<br><br>
Thanks,<br>
[Your Name]</p>""",
                    variant_label="B"
                )
            ]
        ),
        CampaignSequence(
            seq_number=2,
            seq_delay_details=SeqDelayDetails(delay_in_days=3),
            subject="",
            email_body=f"""<p>Hi,<br><br>
Thanks for your interest! Here are more details about the {job_description} opportunities:<br><br>
<strong>Role Details:</strong><br>
• [Specific responsibilities]<br>
• [Required skills and experience]<br>
• [Team and company information]<br><br>
<strong>Benefits:</strong><br>
• [Compensation and benefits]<br>
• [Growth opportunities]<br>
• [Work environment]<br><br>
Would you be interested in a quick call to discuss this role in more detail?<br><br>
Best regards,<br>
[Your Name]</p>"""
        ),
                CampaignSequence(
            seq_number=3,
            seq_delay_details=SeqDelayDetails(delay_in_days=5),
            subject="",
            email_body=f"""<p>Hi,<br><br>
Just wanted to follow up on the {job_description} opportunity I shared.<br><br>
Have you had a chance to review the information? I'd love to hear your thoughts and answer any questions.<br><br>
If you're interested, I can help schedule next steps. If not, no worries at all!<br><br>
Thanks for your time!<br>
[Your Name]</p>"""
        )
    ]
    
    return sequences

# ============================================================================
# RATE LIMITING MIDDLEWARE
# ============================================================================

class RateLimiter:
    def __init__(self, max_requests: int = 10, window_seconds: int = 2):
        self.max_requests = max_requests
        self.window_seconds = window_seconds
        self.requests = []
    
    def is_allowed(self) -> bool:
        now = time.time()
        # Remove old requests outside the window
        self.requests = [req_time for req_time in self.requests if now - req_time < self.window_seconds]
        
        if len(self.requests) >= self.max_requests:
            return False
        
        self.requests.append(now)
        return True

# Global rate limiter instance
rate_limiter = RateLimiter(max_requests=10, window_seconds=2)

@app.middleware("http")
async def rate_limit_middleware(request: Request, call_next):
    """Rate limiting middleware to respect Smartlead's API limits"""
    if not rate_limiter.is_allowed():
        return JSONResponse(
            status_code=429,
            content={
                "error": "Rate limit exceeded",
                "message": "Too many requests. Please wait before making another request.",
                "retry_after": 2
            }
        )
    
    response = await call_next(request)
    return response

# ============================================================================
# ERROR HANDLING
# ============================================================================

@app.exception_handler(HTTPException)
async def http_exception_handler(request: Request, exc: HTTPException):
    """Custom HTTP exception handler"""
    return JSONResponse(
        status_code=exc.status_code,
        content={
            "error": True,
            "message": exc.detail,
            "status_code": exc.status_code,
            "timestamp": datetime.now().isoformat()
        }
    )

@app.exception_handler(Exception)
async def general_exception_handler(request: Request, exc: Exception):
    """General exception handler"""
    return JSONResponse(
        status_code=500,
        content={
            "error": True,
            "message": "Internal server error",
            "detail": str(exc) if os.getenv("DEBUG", "false").lower() == "true" else "An unexpected error occurred",
            "timestamp": datetime.now().isoformat()
        }
    )

# ============================================================================
# CUSTOM OPENAPI SCHEMA
# ============================================================================

def custom_openapi():
    if app.openapi_schema:
        return app.openapi_schema
    
    openapi_schema = get_openapi(
        title="Smartlead API - Complete Integration",
        version="2.0.0",
        description="""
        # Smartlead API - Complete Integration
        
        A comprehensive FastAPI wrapper for the Smartlead email automation platform.
        
        ## Features
        - **Campaign Management**: Create, update, and manage email campaigns
        - **Lead Management**: Add, update, and manage leads across campaigns
        - **Sequence Management**: Create and manage email sequences with AI generation
        - **Webhook Management**: Set up webhooks for real-time notifications
        - **Analytics**: Get detailed campaign analytics and statistics
        - **Email Account Management**: Manage email accounts and warmup
        - **Client Management**: Handle client accounts and permissions
        
        ## Authentication
        All requests require a Smartlead API key passed as a query parameter: `?api_key=YOUR_API_KEY`
        
        ## Rate Limits
        - 10 requests per 2 seconds (enforced automatically)
        
        ## Base URL
        - Smartlead API: `https://server.smartlead.ai/api/v1`
        """,
        routes=app.routes,
    )
    
    # Add custom tags
    openapi_schema["tags"] = [
        {"name": "Campaigns", "description": "Campaign management operations"},
        {"name": "Leads", "description": "Lead management operations"},
        {"name": "Sequences", "description": "Email sequence management"},
        {"name": "Webhooks", "description": "Webhook management"},
        {"name": "Clients", "description": "Client account management"},
        {"name": "Messages", "description": "Message history and reply operations"},
        {"name": "Analytics", "description": "Campaign analytics and statistics"},
        {"name": "Email Accounts", "description": "Email account management"},
        {"name": "Utilities", "description": "Utility endpoints"}
    ]
    
    app.openapi_schema = openapi_schema
    return app.openapi_schema

app.openapi = custom_openapi

# ============================================================================
# MAIN APPLICATION ENTRY POINT
# ============================================================================

if __name__ == "__main__":
    import uvicorn
    
    print("�� Starting Smartlead API - Complete Integration")
    print(f"�� API Documentation: http://localhost:8000/docs")
    print(f"📖 ReDoc Documentation: http://localhost:8000/redoc")
    print(f"�� Smartlead Base URL: {SMARTLEAD_BASE_URL}")
    print(f"⚡ Rate Limit: 10 requests per 2 seconds")
    
    uvicorn.run(
        "final:app",
        host="0.0.0.0",
        port=8000,
        reload=True,
        log_level="info"
    )