import os
import json
import time
import threading
from fastapi import FastAPI, HTTPException, BackgroundTasks
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import JSONResponse
import uvicorn
from typing import Dict
from datetime import datetime

# Import from parallel_miner_v3
from parallel_miner_v3 import ParallelMiner, MiningCore, HashUnit

# FastAPI App Definition
app = FastAPI(
    title="Bitcoin Mining API", 
    description="API endpoints for Bitcoin mining operations using electron-speed SHA-256", 
    version="3.0.0"
)

# Add CORS middleware to allow cross-origin requests
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],  # Allows all origins
    allow_credentials=True,
    allow_methods=["*"],  # Allows all methods
    allow_headers=["*"],
)

# Stats file path
STATS_FILE = "mining_stats_history.json"

# Global variables to track mining status
miner_instance = None
mining_thread = None
mining_stats = {
    "is_mining": False,
    "total_hashes": 0,
    "blocks_found": 0,
    "hash_rate": 0.0,
    "best_hash": None,
    "best_hash_difficulty": 0,
    "start_time": None,
    "total_runtime": 0,  # Cumulative runtime across all sessions
    "session_count": 0,
    "best_session_hashrate": 0,
    "all_time_total_hashes": 0,
    "logs": []
}

def save_mining_stats():
    """Save mining statistics to file"""
    try:
        if os.path.exists(STATS_FILE):
            with open(STATS_FILE, 'r') as f:
                historical_stats = json.load(f)
        else:
            historical_stats = {"sessions": []}
        
        # Calculate final stats for this session
        end_time = time.time()
        elapsed = end_time - mining_stats["start_time"] if mining_stats["start_time"] else 0
        hash_rate = mining_stats["total_hashes"] / elapsed if elapsed > 0 else 0
        
        session_stats = {
            "timestamp": datetime.now().strftime("%Y-%m-%d %H:%M:%S"),
            "duration": f"{elapsed:.2f}s",
            "total_hashes": mining_stats["total_hashes"],
            "avg_hash_rate": f"{hash_rate/1000:.2f} KH/s",
            "blocks_found": mining_stats["blocks_found"],
            "best_hash": mining_stats["best_hash"].hex() if mining_stats["best_hash"] else None,
            "best_hash_difficulty": mining_stats["best_hash_difficulty"]
        }
        
        historical_stats["sessions"].append(session_stats)
        historical_stats["total_runtime"] = mining_stats["total_runtime"] + elapsed
        historical_stats["total_hashes"] = mining_stats["all_time_total_hashes"] + mining_stats["total_hashes"]
        historical_stats["total_blocks"] = sum(s["blocks_found"] for s in historical_stats["sessions"])
        historical_stats["best_session_hashrate"] = max(
            mining_stats["best_session_hashrate"],
            hash_rate/1000  # Convert to KH/s
        )
        
        with open(STATS_FILE, 'w') as f:
            json.dump(historical_stats, f, indent=2)
            
    except Exception as e:
        log_mining(f"Error saving mining stats: {str(e)}")

def log_mining(message):
    """Add a mining log message with timestamp"""
    timestamp = datetime.now().strftime("%H:%M:%S")
    log_entry = f"[{timestamp}] {message}"
    mining_stats["logs"].append(log_entry)
    
    # Keep only the last 100 logs
    if len(mining_stats["logs"]) > 100:
        mining_stats["logs"] = mining_stats["logs"][-100:]
    
    print(log_entry)

@app.on_event("startup")
async def startup_event():
    """Initialize mining components and start mining on startup"""
    global miner_instance, mining_thread, mining_stats
    if not miner_instance:
        log_mining("🚀 Initializing Bitcoin mining components...")
        miner_instance = ParallelMiner(num_cores=5)  # Increased cores for better performance
        
        # Initialize mining stats
        mining_stats["is_mining"] = True
        mining_stats["start_time"] = time.time()
        mining_stats["total_hashes"] = 0
        mining_stats["blocks_found"] = 0
        mining_stats["best_hash"] = None
        
        # Start mining in background thread
        mining_thread = threading.Thread(
            target=miner_instance.start_mining,
            kwargs={"duration": None}  # Run forever
        )
        mining_thread.daemon = True
        mining_thread.start()
        
        log_mining(f"Started mining automatically with {len(miner_instance.cores)} cores")

from fastapi.staticfiles import StaticFiles

# app.mount("/static", StaticFiles(directory="static"), name="static")

# Serve your main HTML file
@app.get("/")
async def root():
    return ()
    
    # return FileResponse("index.html")

# # Optional: If you need to serve other static files individually
# @app.get("/{filename}")
# async def serve_file(filename: str):
#     if filename in ['style.css', 'script.js']:
#         return FileResponse(f"static/{filename}")
#     return FileResponse(f"static/{filename}")



@app.get("/mining/status")
async def get_mining_status():
    """Get current mining status and statistics"""
    if not miner_instance:
        return {"error": "Mining system not initialized"}
        
    current_time = time.time()
    if mining_stats["start_time"]:
        elapsed = current_time - mining_stats["start_time"]
        hash_rate = mining_stats["total_hashes"] / elapsed if elapsed > 0 else 0
    else:
        hash_rate = 0

    return {
        "is_mining": mining_stats["is_mining"],
        "total_hashes": mining_stats["total_hashes"],
        "hash_rate": f"{hash_rate/1000:.2f} KH/s",
        "blocks_found": mining_stats["blocks_found"],
        "best_hash": mining_stats["best_hash"].hex() if mining_stats["best_hash"] else None,
        "uptime": f"{elapsed:.2f}s" if mining_stats["start_time"] else "0s",
        "cores_active": len(miner_instance.cores) if miner_instance else 0,
        "units_per_core": len(miner_instance.cores[0].units) if miner_instance and miner_instance.cores else 0,
        "logs": mining_stats["logs"][-10:]  # Last 10 logs
    }

@app.get("/mining/performance")
async def get_mining_performance():
    """Get detailed mining performance metrics"""
    global miner_instance, mining_stats
    
    if not miner_instance:
        return {"error": "Mining system not initialized"}
    
    current_time = time.time()
    if mining_stats["start_time"]:
        elapsed = current_time - mining_stats["start_time"]
        hash_rate = mining_stats["total_hashes"] / elapsed if elapsed > 0 else 0
        hashes_per_core = mining_stats["total_hashes"] / len(miner_instance.cores) if miner_instance.cores else 0
    else:
        elapsed = 0
        hash_rate = 0
        hashes_per_core = 0
    
    core_stats = []
    if miner_instance and miner_instance.cores:
        for i, core in enumerate(miner_instance.cores):
            core_stats.append({
                "core_id": i,
                "active_units": len(core.units),
                "status": "active" if mining_stats["is_mining"] else "idle"
            })
    
    return {
        "overall_performance": {
            "hash_rate": f"{hash_rate/1000:.2f} KH/s",
            "total_hashes": mining_stats["total_hashes"],
            "blocks_found": mining_stats["blocks_found"],
            "uptime": f"{elapsed:.2f}s",
            "hashes_per_core": f"{hashes_per_core/1000:.2f}K"
        },
        "core_utilization": {
            "total_cores": len(miner_instance.cores),
            "active_cores": len([c for c in core_stats if c["status"] == "active"]),
            "cores": core_stats
        },
        "memory_usage": {
            "core_memory": len(miner_instance.cores) * 1024 * 1024,  # Approximate memory usage per core
            "total_allocated": len(miner_instance.cores) * len(miner_instance.cores[0].units) * 1024 if miner_instance.cores else 0
        }
    }

from fastapi.encoders import jsonable_encoder


@app.post("/mining/start")
async def start_mining():
    """Start Bitcoin mining operations if not already running"""
    global mining_thread, miner_instance, mining_stats
    
    if mining_stats["is_mining"]:
        return {"message": "Mining is already running", "status": "already_running"}
    
    if not miner_instance:
        miner_instance = ParallelMiner()
    
    # Reset statistics
    mining_stats["is_mining"] = True
    mining_stats["start_time"] = time.time()
    mining_stats["total_hashes"] = 0
    mining_stats["blocks_found"] = 0
    mining_stats["best_hash"] = None
    
    # Start mining in background thread
    mining_thread = threading.Thread(
        target=miner_instance.start_mining,
        kwargs={"duration": None}  # Always run indefinitely
    )
    mining_thread.daemon = True
    mining_thread.start()
    
    log_mining(f"Started mining with {len(miner_instance.cores)} cores")
    
    return {
        "message": "Mining started successfully",
        "status": "started",
        "config": {
            "cores": len(miner_instance.cores),
            "units_per_core": len(miner_instance.cores[0].units),
            "duration": "indefinite",
        }
    }

@app.post("/mining/stop")
async def stop_mining():
    """Stop Bitcoin mining operations"""
    global miner_instance, mining_stats
    
    if not mining_stats["is_mining"]:
        return {"message": "Mining is not currently running", "status": "not_running"}
    
    if miner_instance:
        miner_instance.mining = False
        mining_stats["is_mining"] = False
        
        # Calculate final statistics
        end_time = time.time()
        elapsed = end_time - mining_stats["start_time"]
        hash_rate = mining_stats["total_hashes"] / elapsed if elapsed > 0 else 0
        
        # Update cumulative statistics
        mining_stats["total_runtime"] += elapsed
        mining_stats["all_time_total_hashes"] += mining_stats["total_hashes"]
        mining_stats["best_session_hashrate"] = max(
            mining_stats["best_session_hashrate"],
            hash_rate/1000  # KH/s
        )
        
        # Save stats to file
        save_mining_stats()
        
        # Log comprehensive statistics
        log_mining("=== Mining Session Completed ===")
        log_mining(f"Session Duration: {elapsed:.2f}s")
        log_mining(f"Total Hashes: {mining_stats['total_hashes']:,}")
        log_mining(f"Average Hash Rate: {hash_rate/1000:.2f} KH/s")
        log_mining(f"Blocks Found: {mining_stats['blocks_found']}")
        log_mining(f"Best Hash: {mining_stats['best_hash'].hex() if mining_stats['best_hash'] else 'None'}")
        log_mining(f"Best Hash Difficulty: {mining_stats['best_hash_difficulty']}")
        log_mining("\n=== All-Time Statistics ===")
        log_mining(f"Total Runtime: {mining_stats['total_runtime']:.2f}s")
        log_mining(f"Total Hashes: {mining_stats['all_time_total_hashes']:,}")
        log_mining(f"Total Blocks Found: {mining_stats['blocks_found']}")
        log_mining(f"Best Session Hash Rate: {mining_stats['best_session_hashrate']:.2f} KH/s")
        
        return {
            "message": "Mining stopped successfully",
            "status": "stopped",
            "session_stats": {
                "duration": f"{elapsed:.2f}s",
                "total_hashes": mining_stats["total_hashes"],
                "avg_hash_rate": f"{hash_rate/1000:.2f} KH/s",
                "blocks_found": mining_stats["blocks_found"],
                "best_hash": mining_stats["best_hash"].hex() if mining_stats["best_hash"] else None,
                "best_hash_difficulty": mining_stats["best_hash_difficulty"]
            },
            "all_time_stats": {
                "total_runtime": f"{mining_stats['total_runtime']:.2f}s",
                "total_hashes": mining_stats["all_time_total_hashes"],
                "total_blocks": mining_stats["blocks_found"],
                "best_session_hashrate": f"{mining_stats['best_session_hashrate']:.2f} KH/s"
            }
        }
    
    return {"message": "Mining instance not found", "status": "error"}

 
@app.get("/mining/history")
async def get_mining_history():
    """Get historical mining statistics"""
    try:
        if os.path.exists(STATS_FILE):
            with open(STATS_FILE, 'r') as f:
                historical_stats = json.load(f)
            return historical_stats
        else:
            return {
                "sessions": [],
                "total_runtime": 0,
                "total_hashes": 0,
                "total_blocks": 0,
                "best_session_hashrate": 0
            }
    except Exception as e:
        raise HTTPException(status_code=500, detail=f"Error reading mining history: {str(e)}")

def handle_shutdown():
    """Handle graceful shutdown and save statistics"""
    if mining_stats["is_mining"] and miner_instance:
        log_mining("\n🛑 Server shutdown detected - Saving final mining statistics...")
        miner_instance.mining = False
        mining_stats["is_mining"] = False
        
        # Calculate and save final statistics
        end_time = time.time()
        elapsed = end_time - mining_stats["start_time"]
        hash_rate = mining_stats["total_hashes"] / elapsed if elapsed > 0 else 0
        
        # Update cumulative statistics
        mining_stats["total_runtime"] += elapsed
        mining_stats["all_time_total_hashes"] += mining_stats["total_hashes"]
        mining_stats["best_session_hashrate"] = max(
            mining_stats["best_session_hashrate"],
            hash_rate/1000
        )
        
        # Log final stats before shutdown
        log_mining("=== Final Mining Statistics ===")
        log_mining(f"Session Duration: {elapsed:.2f}s")
        log_mining(f"Total Hashes: {mining_stats['total_hashes']:,}")
        log_mining(f"Average Hash Rate: {hash_rate/1000:.2f} KH/s")
        log_mining(f"Blocks Found: {mining_stats['blocks_found']}")
        if mining_stats["best_hash"]:
            log_mining(f"Best Hash: {mining_stats['best_hash'].hex()}")
        
        # Save stats to file
        save_mining_stats()
        log_mining("Statistics saved successfully")
        log_mining("Server shutting down... Goodbye! 👋")

if __name__ == "__main__":
    # Start the FastAPI server
    print("Starting Bitcoin Mining API Server...")
    print("API Documentation will be available at: http://localhost:8000/docs")
    print("API Root endpoint: http://localhost:8000/")
    print("\nEndpoints:")
    print(" - GET  /mining/status - Current mining status")
    print(" - GET  /mining/performance - Detailed performance metrics")
    print(" - GET  /mining/history - Historical mining statistics")
    print(" - POST /mining/start - Start mining (if stopped)")
    print(" - POST /mining/stop  - Stop mining and show stats")
    print("\nPress Ctrl+C to stop mining and save statistics")
    
    try:
        uvicorn.run(
            app, 
            host="0.0.0.0", 
            port=8000, 
            log_level="info",
            reload=False  # Set to False for production
        )
    except KeyboardInterrupt:
        handle_shutdown()
    except Exception as e:
        log_mining(f"Error during server operation: {str(e)}")
        handle_shutdown()
        raise