from flask import Flask, jsonify, request
import sqlite3
import json
import os

app = Flask(__name__)
db_path = '/opt/ssd_health/drive_records.db'

# init db function
def init_db():
    print("Initializing DB")
    db_check = "SELECT name FROM sqlite_master WHERE type='table' AND name='drive_records';"
    create_table_command = """
    CREATE TABLE drive_records (
        id INTEGER PRIMARY KEY, 
        serial TEXT NOT NULL,
        model TEXT NOT NULL, 
        flavor TEXT NOT NULL, 
        capacity TEXT NOT NULL, 
        TBW TEXT NOT NULL, 
        smart TEXT NOT NULL
    );
    """
    # this code deletes the db file if 0 bytes
    if os.path.exists(db_path) and os.path.getsize(db_path) == 0:
        try:
            os.remove(db_path)
            print("Database is 0 bytes, deleting.")
        except Exception as e:
            print(f"error during file deletion - 405: {e}")
            return jsonify({'error during file deletion': e}), 405  
    try:
        result = bool(query_db(db_check))
        print(result)
        # Check if any tables were found
        if result:
            print("drive_records exists - 205")
            #return jsonify({'drive_records exists - 205': result}), 205
        else:
            print("drive_records does not exist, creating")
            try:
                result_init = query_db(create_table_command)
                print("Database created - 201")
                #return jsonify({'Database created': True, 'Result': result_init}), 201            
            except sqlite3.Error as e:
                print(f"error during table initialization: {e}")    
                return jsonify({'error during table initialization - 401': e}), 401
        #return len(result) > 0
    except sqlite3.Error as e:
        print(f"error during table check: {e}")
        return jsonify({'error during table check - 400': e}), 400

# sqlite query function
def query_db(sql_query):
    try:
        # Establish a connection to the SQLite database using a context manager
        with sqlite3.connect(db_path) as conn:
            cursor = conn.cursor()
            print("Executing SQL query:", sql_query)
            cursor.execute(sql_query)
            rows = cursor.fetchall()
        return rows
    except sqlite3.Error as e:
        # Handle any potential errors that might occur during database operations
        print("An error occurred:", e)
        return []    
    #conn = sqlite3.connect(db_path)
    #cursor = conn.cursor()
    #cursor.execute(sql_query)
    #rows = cursor.fetchall()
    #conn.close()
    #return rows

# Function to return all drive records in database
def get_all_drive_records():
    get_all_drives = "SELECT * FROM drive_records"
    rows = query_db(get_all_drives)    
    drives = []
    for row in rows:
        drive = {
            'id': row[0],
            'serial': row[1],
            'model': row[2],
            'flavor': row[3],
            'capacity': row[4],
            'TBW': row[5],
            'smart': row[6]
        }
        drives.append(drive)
    return jsonify(drives)

# Function to check if a serial number exists in the database
def check_serial_exists(serial):
    serial_check = f"SELECT * FROM drive_records WHERE serial='{serial}'"
    print(serial_check)
    return bool(query_db(serial_check))

# Route to check if a serial number exists in the database
@app.route('/check', methods=['GET'])
def check():
    serial_lookup = request.args.get('serial_lookup')
    print(f"Serial to check: {serial_lookup}")
    if not serial_lookup:
        return jsonify({'error': 'No serial number provided'}), 400
    
    exists = check_serial_exists(serial_lookup)
    return jsonify({'serial_number_exists': exists})

# Route to get all drive records in JSON format
@app.route('/drives', methods=['GET'])
def index():
    return get_all_drive_records()

# Route to add drive in database
# serial,model,flavor,capacity,TBW,smart
@app.route('/add_drive', methods=['GET'])
def add_drive():
    serial = request.args.get('serial')
    model = request.args.get('model')
    flavor = request.args.get('flavor')
    capacity = request.args.get('capacity')
    TBW = request.args.get('TBW')
    smart = request.args.get('smart')
    if None in [serial, model, flavor, capacity, TBW, smart]:
        return jsonify({'error': 'Missing required query parameter(s)'}), 400
    add_drive_query = f"INSERT INTO drive_records (serial, model, flavor, capacity, TBW, smart) VALUES ('{serial}', '{model}', '{flavor}', '{capacity}', '{TBW}', '{smart}'); "
    print(add_drive_query)
    return jsonify(query_db(add_drive_query))

# Route to update drive in database
# serial,TBW,smart
@app.route('/update_drive', methods=['GET'])
def update_drive():
    serial = request.args.get('serial')
    TBW = request.args.get('TBW')
    smart = request.args.get('smart')
    if None in [serial, TBW, smart]:
        return jsonify({'error': 'Missing required query parameter(s)'}), 400
    update_drive_query = f"UPDATE drive_records SET TBW = '{TBW}', smart = '{smart}' WHERE serial = '{serial}';"   
    print(update_drive_query)
    return jsonify(query_db(update_drive_query))

# test route
@app.route('/test', methods=['GET'])
def test():
    db_check = "SELECT name FROM sqlite_master WHERE type='table' AND name='drive_records';"
    return query_db(db_check)

if __name__ == '__main__':
    result=init_db()
    print(result)
    app.run(debug=True, host='0.0.0.0', port=5000)