import gradio as gr
import pandas as pd
import matplotlib.pyplot as plt
import numpy as np
import io
from datetime import datetime, timedelta
import sys
import traceback

# Try to import fpdf2, but allow the app to run without it
try:
    from fpdf2 import FPDF
    FPDF_AVAILABLE = True
    print("FPDF2 successfully loaded.")  # Debug log to confirm fpdf2 installation
except ImportError:
    FPDF_AVAILABLE = False
    FPDF = None
    print("FPDF2 not installed. PDF download feature will be disabled.")

# Check library versions for debugging
debug_msg = "Library Versions:\n"
try:
    debug_msg += f"Python: {sys.version}\n"
    debug_msg += f"Gradio: {gr.__version__}\n"
    debug_msg += f"Pandas: {pd.__version__}\n"
    debug_msg += f"Matplotlib: {matplotlib.__version__}\n"
    debug_msg += f"NumPy: {np.__version__}\n"
    if FPDF_AVAILABLE:
        debug_msg += f"FPDF2: {FPDF.__version__}\n"
    else:
        debug_msg += "FPDF2: Not installed (PDF download feature disabled)\n"
except Exception as e:
    debug_msg += f"Error checking library versions: {str(e)}\n"

# Global DataFrame to store the CSV data
df = pd.DataFrame()

def upload_csv(file):
    global df
    debug_msg_local = debug_msg + "\nStarting CSV upload process...\n"
    try:
        if file is None:
            debug_msg_local += "No file uploaded. Please upload a CSV file.\n"
            print(debug_msg_local)  # Log to console for debugging
            return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None
        
        # Read the CSV file with encoding handling
        debug_msg_local += "Reading CSV file...\n"
        try:
            df = pd.read_csv(file, encoding='utf-8')
        except UnicodeDecodeError:
            debug_msg_local += "Error: CSV file encoding is not UTF-8. Trying latin1 encoding...\n"
            df = pd.read_csv(file, encoding='latin1')
        except Exception as e:
            debug_msg_local += f"Error reading CSV file: {str(e)}\n{traceback.format_exc()}\n"
            print(debug_msg_local)
            return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None
        
        if df.empty:
            debug_msg_local += "The uploaded CSV file is empty.\n"
            print(debug_msg_local)
            return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None
        
        # Debug: Show the CSV column names (limit verbosity)
        debug_msg_local += f"CSV Columns: {', '.join(df.columns)}\n"
        
        # Define required columns
        required_columns = {'DeviceID', 'Lab', 'Type', 'Timestamp', 'Status', 'UsageCount'}
        if not required_columns.issubset(df.columns):
            missing_cols = required_columns - set(df.columns)
            debug_msg_local += f"Error: CSV is missing required columns: {', '.join(missing_cols)}\n"
            print(debug_msg_local)
            return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None
        
        # Debug: Check data types and sample values (limit to 5 rows)
        debug_msg_local += f"Data Types:\n{df.dtypes.to_string()}\n"
        debug_msg_local += f"Sample Values (first 5 rows):\n{df.head(5).to_string()}\n"
        
        # Check for empty or all-NaN columns
        if df['Lab'].dropna().empty:
            debug_msg_local += "Error: Lab column is empty or contains only NaN values.\n"
        if df['Type'].dropna().empty:
            debug_msg_local += "Error: Type column is empty or contains only NaN values.\n"
        if df['Lab'].dropna().empty or df['Type'].dropna().empty:
            print(debug_msg_local)
            return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None
        
        # Convert Timestamp to datetime with a specific format and fallback
        debug_msg_local += "Converting Timestamp column...\n"
        try:
            # Try parsing with a common format first
            df['Timestamp'] = pd.to_datetime(df['Timestamp'], format='%Y-%m-%d %H:%M:%S', errors='coerce')
            # If parsing fails for some rows, try without a specific format
            if df['Timestamp'].isna().any():
                debug_msg_local += "Some timestamps failed to parse with format '%Y-%m-%d %H:%M:%S'. Falling back to generic parsing...\n"
                df['Timestamp'] = pd.to_datetime(df['Timestamp'], errors='coerce')
            timestamps_invalid = df['Timestamp'].isna().all()
            if timestamps_invalid:
                debug_msg_local += "Warning: All Timestamp values are invalid or unparseable. Date range filtering will be disabled.\n"
        except Exception as e:
            debug_msg_local += f"Error parsing Timestamp column: {str(e)}\n{traceback.format_exc()}\n"
            print(debug_msg_local)
            return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None
        
        # Extract unique values for dropdowns
        debug_msg_local += "Extracting unique values for dropdowns...\n"
        labs = ['All'] + sorted([str(lab) for lab in df['Lab'].dropna().unique()])
        types = ['All'] + sorted([str(v) for v in df['Type'].dropna().unique()])
        debug_msg_local += f"Lab options: {', '.join(labs)}\nType options: {', '.join(types)}\n"
        
        # Extract date range for filter
        if timestamps_invalid:
            date_ranges = ['All']
            debug_msg_local += "Date range dropdown disabled due to invalid timestamps.\n"
        else:
            min_date = df['Timestamp'].min()
            max_date = df['Timestamp'].max()
            if pd.isna(min_date) or pd.isna(max_date):
                date_ranges = ['All']
                debug_msg_local += "Warning: Could not determine date range due to invalid timestamps.\n"
            else:
                min_date_str = min_date.strftime('%Y-%m-%d')
                max_date_str = max_date.strftime('%Y-%m-%d')
                date_ranges = ['All', f"{min_date_str} to {max_date_str}"]
                debug_msg_local += f"Date Range: {min_date_str} to {max_date_str}\n"
        
        # Automatically trigger filter_and_visualize after upload with default filters
        debug_msg_local += "Triggering initial visualization with default filters...\n"
        try:
            device_cards, plot_daily, plot_uptime, anomaly_text, filter_msg = filter_and_visualize("All", "All", "All")
            debug_msg_local += f"Initial Filter Result: {filter_msg}\n"
        except Exception as e:
            debug_msg_local += f"Initial Filter Error: {str(e)}\n{traceback.format_exc()}\n"
            device_cards, plot_daily, plot_uptime, anomaly_text = None, None, None, None
        
        # Truncate debug message to prevent Gradio rendering issues
        debug_msg_local = debug_msg_local[:5000]  # Limit to 5000 characters
        print(debug_msg_local)
        return labs, types, date_ranges, debug_msg_local, "All", "All", "All", device_cards, plot_daily, plot_uptime, anomaly_text
    except Exception as e:
        debug_msg_local += f"Failed to process CSV: {str(e)}\n{traceback.format_exc()}\n"
        debug_msg_local = debug_msg_local[:5000]  # Limit to 5000 characters
        print(debug_msg_local)
        return ["All"], ["All"], ["All"], debug_msg_local, "All", "All", "All", None, None, None, None

def filter_and_visualize(selected_lab, selected_type, selected_date_range):
    global df
    error_msg = "Starting filter and visualize process...\n"
    try:
        if df.empty:
            error_msg += "No data available.\n"
            print(error_msg)
            return None, None, None, None, error_msg
        
        # Debug: Log the filter parameters
        error_msg += f"Applying filters: Lab={selected_lab}, Type={selected_type}, Date Range={selected_date_range}\n"
        
        # Filter the DataFrame
        filtered_df = df.copy()
        error_msg += f"Initial DataFrame: {len(filtered_df)} rows\n"
        
        if selected_lab != "All":
            filtered_df = filtered_df[filtered_df["Lab"] == selected_lab]
            error_msg += f"After Lab filter ({selected_lab}): {len(filtered_df)} rows\n"
        if selected_type != "All":
            filtered_df = filtered_df[filtered_df["Type"] == selected_type]
            error_msg += f"After Type filter ({selected_type}): {len(filtered_df)} rows\n"
        if selected_date_range != "All" and selected_date_range != "No data available." and not df['Timestamp'].isna().all():
            try:
                start_date, end_date = selected_date_range.split(" to ")
                start_date = pd.to_datetime(start_date)
                end_date = pd.to_datetime(end_date) + timedelta(days=1)  # Include end date
                filtered_df = filtered_df[(filtered_df["Timestamp"] >= start_date) & (filtered_df["Timestamp"] < end_date)]
                error_msg += f"After Date Range filter ({start_date} to {end_date}): {len(filtered_df)} rows\n"
            except Exception as e:
                error_msg += f"Error parsing date range: {str(e)}\n{traceback.format_exc()}\n"
        
        if filtered_df.empty:
            error_msg += "No data matches the selected filters.\n"
            print(error_msg)
            return None, None, None, None, error_msg
        
        # Debug: Log the filtered DataFrame (limit verbosity)
        error_msg += f"Filtered DataFrame (first 5 rows):\n{filtered_df.head(5).to_string()}\n"
        
        # Device Cards (as a table)
        device_cards = filtered_df[['DeviceID', 'Lab', 'Type', 'UsageCount', 'Timestamp']].sort_values(by='Timestamp', ascending=False)
        
        # Daily Log Trends (Line Chart)
        try:
            if df['Timestamp'].isna().all():
                error_msg += "Warning: All timestamps are invalid. Skipping Daily Log Trends.\n"
                plt.figure(figsize=(8, 4))
                plt.title("Daily Log Trends - No Data (Invalid Timestamps)")
                plt.xlabel("Date")
                plt.ylabel("Number of Logs")
                plot_daily = io.BytesIO()
                plt.savefig(plot_daily, format="png", bbox_inches="tight")
                plt.close()
                plot_daily.seek(0)
            else:
                daily_logs = filtered_df.groupby(filtered_df['Timestamp'].dt.date).size()
                if daily_logs.empty:
                    error_msg += "Warning: No data for Daily Log Trends.\n"
                    plt.figure(figsize=(8, 4))
                    plt.title("Daily Log Trends - No Data")
                    plt.xlabel("Date")
                    plt.ylabel("Number of Logs")
                    plot_daily = io.BytesIO()
                    plt.savefig(plot_daily, format="png", bbox_inches="tight")
                    plt.close()
                    plot_daily.seek(0)
                else:
                    plt.figure(figsize=(8, 4))
                    daily_logs.plot(kind='line', marker='o', color='blue')
                    plt.title("Daily Log Trends")
                    plt.xlabel("Date")
                    plt.ylabel("Number of Logs")
                    plt.xticks(rotation=45)
                    plot_daily = io.BytesIO()
                    plt.savefig(plot_daily, format="png", bbox RACinches="tight")
                    plt.close()
                    plot_daily.seek(0)
        except Exception as e:
            error_msg += f"Error generating Daily Log Trends: {str(e)}\n{traceback.format_exc()}\n"
            plt.figure(figsize=(8, 4))
            plt.title("Daily Log Trends - Error")
            plt.xlabel("Date")
            plt.ylabel("Number of Logs")
            plot_daily = io.BytesIO()
            plt.savefig(plot_daily, format="png", bbox_inches="tight")
            plt.close()
            plot_daily.seek(0)
        
        # Weekly Uptime % (Bar Chart)
        try:
            if df['Timestamp'].isna().all():
                error_msg += "Warning: All timestamps are invalid. Skipping Weekly Uptime.\n"
                plt.figure(figsize=(8, 4))
                plt.title("Weekly Uptime % - No Data (Invalid Timestamps)")
                plt.xlabel("Date")
                plt.ylabel("Uptime %")
                plot_uptime = io.BytesIO()
                plt.savefig(plot_uptime, format="png", bbox_inches="tight")
                plt.close()
                plot_uptime.seek(0)
            else:
                end_date = filtered_df['Timestamp'].max()
                start_date = end_date - timedelta(days=7)
                weekly_df = filtered_df[(filtered_df['Timestamp'] >= start_date) & (filtered_df['Timestamp'] <= end_date)]
                if weekly_df.empty:
                    error_msg += "Warning: No data for Weekly Uptime % (date range too narrow).\n"
                    plt.figure(figsize=(8, 4))
                    plt.title("Weekly Uptime % - No Data")
                    plt.xlabel("Date")
                    plt.ylabel("Uptime %")
                    plot_uptime = io.BytesIO()
                    plt.savefig(plot_uptime, format="png", bbox_inches="tight")
                    plt.close()
                    plot_uptime.seek(0)
                else:
                    uptime = weekly_df.groupby(weekly_df['Timestamp'].dt.date)['Status'].apply(lambda x: (x == 'Up').mean() * 100)
                    plt.figure(figsize=(8, 4))
                    uptime.plot(kind='bar', color='green')
                    plt.title("Weekly Uptime %")
                    plt.xlabel("Date")
                    plt.ylabel("Uptime %")
                    plt.xticks(rotation=45)
                    plot_uptime = io.BytesIO()
                    plt.savefig(plot_uptime, format="png", bbox_inches="tight")
                    plt.close()
                    plot_uptime.seek(0)
        except Exception as e:
            error_msg += f"Error generating Weekly Uptime %: {str(e)}\n{traceback.format_exc()}\n"
            plt.figure(figsize=(8, 4))
            plt.title("Weekly Uptime % - Error")
            plt.xlabel("Date")
            plt.ylabel("Uptime %")
            plot_uptime = io.BytesIO()
            plt.savefig(plot_uptime, format="png", bbox_inches="tight")
            plt.close()
            plot_uptime.seek(0)
        
        # Anomaly Alerts (Text)
        try:
            anomalies = filtered_df[(filtered_df['UsageCount'] > 80) | (filtered_df['Status'] == 'Down')]
            if anomalies.empty:
                anomaly_text = "No anomalies detected."
            else:
                anomaly_text = "Anomalies Detected:\n" + anomalies[['DeviceID', 'Lab', 'Type', 'Status', 'UsageCount']].to_string(index=False)
        except Exception as e:
            error_msg += f"Error generating Anomaly Alerts: {str(e)}\n{traceback.format_exc()}\n"
            anomaly_text = "Error generating anomaly alerts."
        
        error_msg = error_msg[:5000]  # Limit to 5000 characters
        print(error_msg)
        return device_cards, plot_daily, plot_uptime, anomaly_text, f"{error_msg}Filters applied successfully."
    except Exception as e:
        error_msg += f"Unexpected error in filter_and_visualize: {str(e)}\n{traceback.format_exc()}\n"
        plt.figure(figsize=(8, 4))
        plt.title("Daily Log Trends - Error")
        plt.xlabel("Date")
        plt.ylabel("Number of Logs")
        plot_daily = io.BytesIO()
        plt.savefig(plot_daily, format="png", bbox_inches="tight")
        plt.close()
        plot_daily.seek(0)
        
        plt.figure(figsize=(8, 4))
        plt.title("Weekly Uptime % - Error")
        plt.xlabel("Date")
        plt.ylabel("Uptime %")
        plot_uptime = io.BytesIO()
        plt.savefig(plot_uptime, format="png", bbox_inches="tight")
        plt.close()
        plot_uptime.seek(0)
        
        error_msg = error_msg[:5000]  # Limit to 5000 characters
        print(error_msg)
        return None, plot_daily, plot_uptime, "Error generating anomaly alerts.", error_msg

def download_pdf(selected_lab, selected_type, selected_date_range):
    global df
    try:
        if not FPDF_AVAILABLE:
            print("PDF download feature disabled: fpdf2 module not installed.")
            return None
        
        if df.empty:
            return None
        
        filtered_df = df.copy()
        if selected_lab != "All":
            filtered_df = filtered_df[filtered_df["Lab"] == selected_lab]
        if selected_type != "All":
            filtered_df = filtered_df[filtered_df["Type"] == selected_type]
        if selected_date_range != "All" and selected_date_range != "No data available." and not df['Timestamp'].isna().all():
            start_date, end_date = selected_date_range.split(" to ")
            start_date = pd.to_datetime(start_date)
            end_date = pd.to_datetime(end_date) + timedelta(days=1)
            filtered_df = filtered_df[(filtered_df["Timestamp"] >= start_date) & (filtered_df["Timestamp"] < end_date)]
        
        if filtered_df.empty:
            return None
        
        pdf = FPDF()
        pdf.add_page()
        pdf.set_font("Arial", size=12)
        pdf.cell(200, 10, txt="LabOps Dashboard Report", ln=True, align='C')
        pdf.ln(10)
        
        for index, row in filtered_df.iterrows():
            line = f"{row['Timestamp']} | {row['DeviceID']} | {row['Lab']} | {row['Type']} | {row['Status']} | {row['UsageCount']}"
            pdf.multi_cell(0, 10, txt=line)
        
        output = io.BytesIO()
        pdf.output(output)
        output.seek(0)
        return output
    except Exception as e:
        print(f"Error in download_pdf: {str(e)}\n{traceback.format_exc()}")
        return None

# Build the Gradio interface
try:
    with gr.Blocks() as demo:
        gr.Markdown("🧪 **Multi-Device LabOps Dashboard**\nMonitor smart lab devices, visualize logs, and generate PDF reports.")

        with gr.Row():
            csv_input = gr.File(label="Upload Device Logs CSV", file_types=[".csv"])
        
        with gr.Row():
            lab_dropdown = gr.Dropdown(label="Filter by Lab", choices=["All"], value="All")
            type_dropdown = gr.Dropdown(label="Filter by Equipment Type", choices=["All"], value="All")
            date_dropdown = gr.Dropdown(label="Filter by Date Range", choices=["All"], value="All")

        with gr.Row():
            submit_btn = gr.Button("Submit Filters")

        with gr.Row():
            device_cards = gr.DataFrame(label="Device Cards (Usage, Last Log)")
            plot_daily = gr.Image(label="Daily Log Trends")
            plot_uptime = gr.Image(label="Weekly Uptime %")

        anomaly_output = gr.Textbox(label="Anomaly Alerts")
        
        with gr.Row():
            download_btn = gr.Button("Download PDF Report", visible=True)  # Always visible since fpdf2 should be installed
        
        error_box = gr.Textbox(label="Status/Error Message", visible=True, interactive=False)

        # Connect the components
        csv_input.change(
            fn=upload_csv,
            inputs=csv_input,
            outputs=[lab_dropdown, type_dropdown, date_dropdown, error_box, lab_dropdown, type_dropdown, date_dropdown, device_cards, plot_daily, plot_uptime, anomaly_output]
        )
        
        submit_btn.click(
            fn=filter_and_visualize,
            inputs=[lab_dropdown, type_dropdown, date_dropdown],
            outputs=[device_cards, plot_daily, plot_uptime, anomaly_output, error_box]
        )
        
        download_btn.click(
            fn=download_pdf,
            inputs=[lab_dropdown, type_dropdown, date_dropdown],
            outputs=gr.File(label="Download PDF")
        )

    demo.launch()
except Exception as e:
    print(f"Error launching Gradio interface: {str(e)}\n{traceback.format_exc()}")