#!/usr/bin/env python3
"""
Debug script to investigate DTS step transition issues.
This script will monitor the DTS process and help identify why transitions aren't being detected.
"""

import sys
import os
import time
from datetime import datetime

# Add the package directory to Python path
sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))

from watermaker_plc_api.services.plc_connection import get_plc_connection
from watermaker_plc_api.models.timer_mappings import (
    get_timer_for_dts_mode,
    get_timer_expected_start_value,
    calculate_timer_progress_percent,
    get_timer_info
)
from watermaker_plc_api.utils.logger import get_logger

logger = get_logger(__name__)

def monitor_dts_transition():
    """Monitor DTS process and detect transition issues"""
    plc = get_plc_connection()
    
    if not plc.connect():
        print("❌ Failed to connect to PLC")
        return
    
    print("🔍 DTS Step Transition Monitor")
    print("=" * 50)
    
    previous_mode = None
    previous_timer_value = None
    step_start_time = None
    
    try:
        while True:
            # Read current system mode
            current_mode = plc.read_holding_register(1000)
            if current_mode is None:
                print("❌ Failed to read R1000 (system mode)")
                time.sleep(2)
                continue
            
            # Check if mode changed
            if current_mode != previous_mode:
                print(f"\n🔄 Mode Change Detected: {previous_mode} → {current_mode}")
                previous_mode = current_mode
                step_start_time = datetime.now()
                previous_timer_value = None
            
            # Get timer for current mode
            timer_address = get_timer_for_dts_mode(current_mode)
            
            if timer_address:
                # Read timer value
                timer_value = plc.read_holding_register(timer_address)
                if timer_value is not None:
                    # Get timer info
                    timer_info = get_timer_info(timer_address)
                    expected_start = get_timer_expected_start_value(timer_address)
                    
                    # Calculate progress
                    progress = calculate_timer_progress_percent(timer_address, timer_value)
                    
                    # Check if timer value changed
                    timer_changed = timer_value != previous_timer_value
                    previous_timer_value = timer_value
                    
                    # Calculate elapsed time since step started
                    elapsed = ""
                    if step_start_time:
                        elapsed_seconds = (datetime.now() - step_start_time).total_seconds()
                        elapsed = f" (elapsed: {elapsed_seconds:.1f}s)"
                    
                    # Print status
                    status_icon = "⏳" if timer_changed else "⚠️"
                    print(f"{status_icon} Mode {current_mode} | Timer R{timer_address}: {timer_value} | "
                          f"Progress: {progress}% | Expected Start: {expected_start}{elapsed}")
                    
                    # Check for potential issues
                    if timer_value == 0 and progress == 0:
                        print("  🚨 Timer is 0 but progress is 0% - possible issue!")
                    elif timer_value > expected_start:
                        print(f"  🚨 Timer value ({timer_value}) > expected start ({expected_start}) - unusual!")
                    elif not timer_changed and timer_value > 0:
                        print("  ⚠️  Timer not counting down - may be stuck!")
                    
                    # Check if step should transition
                    if timer_value == 0 and current_mode == 5:
                        print("  ✅ Step 1 timer completed - should transition to Mode 6 soon")
                    elif timer_value == 0 and current_mode == 6:
                        print("  ✅ Step 2 timer completed - should transition to Mode 7 soon")
                
                else:
                    print(f"❌ Failed to read timer R{timer_address} for mode {current_mode}")
            else:
                print(f"ℹ️  Mode {current_mode} has no associated timer (production/transition mode)")
            
            time.sleep(1)  # Check every second
            
    except KeyboardInterrupt:
        print("\n👋 Monitoring stopped by user")
    except Exception as e:
        print(f"❌ Error during monitoring: {e}")
    finally:
        plc.disconnect()

def check_current_dts_state():
    """Check the current DTS state and provide detailed analysis"""
    plc = get_plc_connection()
    
    if not plc.connect():
        print("❌ Failed to connect to PLC")
        return
    
    print("📊 Current DTS State Analysis")
    print("=" * 40)
    
    try:
        # Read current mode
        current_mode = plc.read_holding_register(1000)
        print(f"Current Mode (R1000): {current_mode}")
        
        if current_mode is None:
            print("❌ Cannot read system mode")
            return
        
        # Get timer for current mode
        timer_address = get_timer_for_dts_mode(current_mode)
        
        if timer_address:
            timer_value = plc.read_holding_register(timer_address)
            timer_info = get_timer_info(timer_address)
            expected_start = get_timer_expected_start_value(timer_address)
            progress = calculate_timer_progress_percent(timer_address, timer_value)
            
            print(f"Timer Address: R{timer_address}")
            print(f"Timer Name: {timer_info.get('name', 'Unknown')}")
            print(f"Current Value: {timer_value}")
            print(f"Expected Start: {expected_start}")
            print(f"Progress: {progress}%")
            print(f"Scale: {timer_info.get('scale', 'direct')}")
            print(f"Unit: {timer_info.get('unit', '')}")
            
            # Analysis
            if timer_value == 0:
                print("✅ Timer completed - step should transition soon")
            elif timer_value == expected_start:
                print("🔄 Timer at start value - step just began")
            elif timer_value > expected_start:
                print("⚠️  Timer value higher than expected - unusual condition")
            else:
                remaining_time = timer_value / 10  # Assuming ÷10 scale
                print(f"⏳ Timer counting down - ~{remaining_time:.1f}s remaining")
        else:
            print("ℹ️  No timer for current mode (production/transition phase)")
        
        # Check other relevant registers
        print("\n🔍 Additional Register Values:")
        
        # Check R71 (command register)
        r71_value = plc.read_holding_register(71)
        print(f"R71 (Command): {r71_value}")
        
        # Check R138 specifically (DTS Step 1 timer)
        r138_value = plc.read_holding_register(138)
        print(f"R138 (DTS Step 1 Timer): {r138_value}")
        
        # Check R128 (DTS Step 2 timer)
        r128_value = plc.read_holding_register(128)
        print(f"R128 (DTS Step 2 Timer): {r128_value}")
        
    except Exception as e:
        print(f"❌ Error during analysis: {e}")
    finally:
        plc.disconnect()

def main():
    """Main function"""
    if len(sys.argv) > 1 and sys.argv[1] == "monitor":
        monitor_dts_transition()
    else:
        check_current_dts_state()
        print("\n💡 To continuously monitor transitions, run:")
        print("   python debug_dts_step_transition.py monitor")

if __name__ == "__main__":
    main()