import os, csv
from pynput import keyboard

class keylogger:
    def __init__(self, data_output_path_relative):
        self.data_output_path : str = data_output_path_relative
        self.filename : str = None
        self.key_counter : dict[str: int] = {}
        self.previously_pressed_key : str = None

    def start(self):
        
        self.filename = "logger.csv"
        files = os.listdir(self.data_output_path)
        if not self.filename in files:
            # write initial csv header
            with open(os.path.join(self.data_output_path, self.filename), mode='w', newline='') as file:
                writer = csv.writer(file)
                writer.writerow(["key", "counter"])
        else:
            # load existing key counter data
            self.read_data()
        
        #start logger
        with keyboard.Listener(on_press=self.on_press) as listener:
            listener.join()
        
    def read_data(self):
        with open(os.path.join(self.data_output_path, self.filename), mode='r') as file:
            reader = csv.reader(file)
            next(reader)  # Skip header
            for row in reader:
                key, counter = row
                self.key_counter[key] = int(counter)
    
    def write_data(self):
        with open(os.path.join(self.data_output_path, self.filename), mode='w', newline='') as file:
            writer = csv.writer(file)
            writer.writerow(["key", "counter"])
            for key, counter in self.key_counter.items():
                writer.writerow([key, counter])
        
    def decode_ctrl_char(self, c):
        if isinstance(c, str) and c.startswith(r"\x") and len(c) == 4:
            try:
                value = int(c[2:], 16)  # hex part after \x
                if 1 <= value <= 26:
                    return f"ctrl_l+{chr(value + 96)}"
                return f"ctrl_l+{value}"
            except ValueError:
                pass
        return c
    def on_press(self, key):
        # get the key name
        key_name = []
        try:
            if(str(key).startswith("Key.")):
                raise AttributeError
            key_name.append(str(key)[1:-1])
        except AttributeError:
            key_name.append(str(key.name))
        
        if r"\x" in key_name[0]:
            key_to_decode = key_name[0]
            key_name=[]
            key_combo = self.decode_ctrl_char(key_to_decode)
            keys = key_combo.split("+")
            if self.previously_pressed_key == "ctrl_l":
                key_name.append(keys[1])
            else:
                key_name.append(keys[0])
                key_name.append(keys[1])
        for k in key_name:
            k = k.lower()
            if (k != self.previously_pressed_key):
                self.previously_pressed_key = k
                print(f"Key pressed: {k}")
            
            self.read_data()
            
            if k in self.key_counter:
                self.key_counter[k] += 1
            else:
                self.key_counter[k] = 1
                
            self.write_data()
    
     
if __name__ == "__main__":
    kl = keylogger(data_output_path_relative="data")
    kl.start()