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# -*- coding: utf-8 -*-

# Install Library
# pip install -U tensorflow[and-cuda] torch torchvision pandas scikit-learn pillow numpy
# pip install -U tf-nightly[and-cuda] torch torchvision pandas scikit-learn pillow numpy
# pip install -U tensorflow torch torchvision pandas scikit-learn pillow numpy
# pip install -U "tensorflow[and-cuda]==2.17.0"
# pip install torch==2.8.0 torchvision==0.23.0

# pip uninstall -y tensorflow tensorflow-cpu tensorflow-intel tensorflow-gpu
# pip cache purge
# # opsi A: nightly bundling CUDA
# pip install -U "tf-nightly[and-cuda]"
# # atau opsi B (kalau A tidak tersedia di index kamu):
# pip install -U tf-nightly


import tensorflow as tf
gpus = tf.config.list_physical_devices('GPU')
print(gpus)
if gpus:
    try:
        # for gpu in gpus:
        #     tf.config.experimental.set_memory_growth(gpu, True)  # no full prealloc
        print(f"GPU aktif: {gpus}")
    except Exception as e:
        print("Set memory growth gagal:", e)
else:
    print("Tidak ada GPU terdeteksi.")


# Clean UP Dataset Make Sure Every Style Same Image
import os

BASE_DIR = "/workspace/dataset"  # ubah sesuai path dataset kamu
START, END = 0, 59            # style0..style59
DRY_RUN = False               # ubah ke False untuk beneran hapus

def main():
    base = os.path.abspath(BASE_DIR)
    ref_dir = os.path.join(base, f"style{START}")
    if not os.path.isdir(ref_dir):
        print(f"❌ Folder {ref_dir} tidak ditemukan.")
        return

    files_ref = sorted([f for f in os.listdir(ref_dir) if f.lower().endswith(".png")])
    print(f"πŸ” Total referensi dari style{START}: {len(files_ref)} file")

    # Cari file yang lengkap di semua style
    complete = []
    missing = {}

    for fname in files_ref:
        ok = True
        for i in range(START, END + 1):
            style_path = os.path.join(base, f"style{i}", fname)
            if not os.path.isfile(style_path):
                ok = False
                missing.setdefault(fname, []).append(f"style{i}")
        if ok:
            complete.append(fname)

    print(f"βœ… Lengkap di semua style: {len(complete)} file")
    print(f"❌ Tidak lengkap: {len(missing)} file")

    # Hapus file yang tidak lengkap dari semua style
    if missing:
        for fname, styles in missing.items():
            for i in range(START, END + 1):
                path = os.path.join(base, f"style{i}", fname)
                if os.path.isfile(path):
                    if not DRY_RUN:
                        os.remove(path)
                    print(f"πŸ—‘οΈ  Hapus {path}")
        print(f"\nπŸ”₯ Selesai! Total {len(missing)} file dibersihkan dari semua style folder.")
    else:
        print("Semua file sudah lengkap di semua style β€” tidak ada yang dihapus.")

if __name__ == "__main__":
    main()

import os
from glob import glob
import pandas as pd

data = []

root_dir = "/workspace/dataset"

for style_id in range(60):
    folder_path = os.path.join(root_dir, f"style{style_id}")
    image_paths = glob(os.path.join(folder_path, "*.png"))

    for path in image_paths:
        label = os.path.splitext(os.path.basename(path))[0]  # ambil nama file tanpa ekstensi
        data.append((path, label, f"style{style_id}"))

df = pd.DataFrame(data, columns=["filepath", "label", "style"])

df

import re
import pandas as pd
from collections import Counter

# --- aturan ketat: 5 karakter, A-Z atau 0-9 saja ---
ALLOWED_REGEX_STRICT = r'^[A-Z0-9]{5}$'
ALLOWED_REGEX_LEN5_ALNUM = r'^[A-Za-z0-9]{5}$'  # kalau mau toleransi lowercase hanya untuk deteksi

# pastikan kolom label rapi untuk diperiksa
df['label'] = df['label'].astype(str).str.strip()

# 1) MASK PELANGGAR (ketat)
invalid_mask = ~df['label'].str.match(ALLOWED_REGEX_STRICT, na=True)
invalid_df = df[invalid_mask].copy()

# 2) KATEGORIKAN PENYEBAB
df['len'] = df['label'].str.len()
too_short = df[df['len'] < 5]
too_long  = df[df['len'] > 5]
has_non_alnum = df[df['label'].str.contains(r'[^A-Za-z0-9]', na=True)]
has_lower     = df[df['label'].str.contains(r'[a-z]', na=True)]  # masih ada huruf kecil?

# 3) KARAKTER NAKAL (non-alnum) YANG MUNCUL
def extract_bad_chars(s: str):
    return re.findall(r'[^A-Za-z0-9]', s)

bad_chars_counter = Counter()
for lab in has_non_alnum['label'].dropna().tolist():
    bad_chars_counter.update(extract_bad_chars(lab))
bad_chars_list = sorted(bad_chars_counter.items(), key=lambda x: -x[1])

# 4) RINGKASAN
print("=== VALIDASI LABEL ===")
print(f"Total data         : {len(df)}")
print(f"Tidak valid (ketat): {len(invalid_df)}")
print(f"- Panjang < 5      : {len(too_short)}")
print(f"- Panjang > 5      : {len(too_long)}")
print(f"- Ada non-alnum    : {len(has_non_alnum)}")
print(f"- Ada lowercase    : {len(has_lower)}")

# contoh beberapa label bermasalah
if len(invalid_df) > 0:
    sampel = invalid_df['label'].head(20).tolist()
    print("\nContoh label tidak valid (maks 20):", sampel)

# karakter non-alnum beserta frekuensinya
if bad_chars_list:
    print("\nKarakter non-alnum yang muncul (char, count):", bad_chars_list[:20])

# 5) SIMPAN DAFTAR PELANGGAR KE CSV (biar bisa diperbaiki manual / rename file)
if len(invalid_df) > 0:
    invalid_df.to_csv("invalid_labels.csv", index=False)
    print("\n>> Disimpan: invalid_labels.csv")

# 6) OPSIONAL: STOP TRAINING JIKA MASIH ADA PELANGGAR
if len(invalid_df) > 0:
    raise ValueError(
        f"Ditemukan {len(invalid_df)} label tidak valid. Perbaiki dulu (lihat invalid_labels.csv)."
    )

# Contoh: validasi panjang label = 5, hanya alphanumeric
# df = df[df['label'].str.match(r'^[a-zA-Z0-9]{5}$')]

df

from sklearn.model_selection import train_test_split

train_df, test_df = train_test_split(df, test_size=0.1, random_state=42, stratify=df['style'])
train_df, val_df = train_test_split(train_df, test_size=0.1, random_state=42, stratify=train_df['style'])

from torchvision import transforms
from PIL import Image

transform = transforms.Compose([
    transforms.Resize((50, 250)),         # Ukuran umum CAPTCHA
    transforms.ToTensor(),
    transforms.Normalize((0.5,), (0.5,))  # Normalisasi ke -1..1
])

def load_image(path):
    img = Image.open(path).convert("L")  # convert to grayscale
    return transform(img)

from torch.utils.data import Dataset

class CaptchaDataset(Dataset):
    def __init__(self, dataframe, transform):
        self.dataframe = dataframe.reset_index(drop=True)
        self.transform = transform

    def __len__(self):
        return len(self.dataframe)

    def __getitem__(self, idx):
        row = self.dataframe.iloc[idx]
        image = Image.open(row.filepath).convert("L")
        image = self.transform(image)
        label = row.label
        return image, label


from tensorflow.keras import mixed_precision
mixed_precision.set_global_policy('mixed_float16')  # aktivasi AMP

import tensorflow as tf
from tensorflow.keras.models import Model
from tensorflow.keras.layers import Input, Conv2D, MaxPooling2D, Reshape, Bidirectional, LSTM, Dense, Dropout, Activation, BatchNormalization
from tensorflow.keras import backend as K

# Define the character set (based on your label data)
# You need to create a character set based on the unique characters in your 'label' column
# For example:
# char_set = sorted(list(set("".join(df['label'].unique()))))
# num_classes = len(char_set) + 1 # +1 for the blank label for CTC

# Placeholder for the actual character set - replace with your data's character set
# char_set = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
char_set = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"
num_classes = len(char_set) + 1 # +1 for the blank label for CTC

# Model parameters
# input_shape = (60, 160, 1) # (height, width, channels)
input_shape = (50, 250, 1) # (height, width, channels)
lstm_units = 128

# Input layer
input_tensor = Input(shape=input_shape, name='input')

# Convolutional layers (CNN)
x = Conv2D(32, (3, 3), activation='relu', padding='same')(input_tensor)
x = BatchNormalization()(x)
x = MaxPooling2D((2, 2))(x)

x = Conv2D(64, (3, 3), activation='relu', padding='same')(x)
x = BatchNormalization()(x)
x = MaxPooling2D((2, 2))(x)

x = Conv2D(128, (3, 3), activation='relu', padding='same')(x)
x = BatchNormalization()(x)
x = MaxPooling2D((2, 2))(x)

# Reshape for RNN
# The output shape of the last pooling layer is (batch_size, height, width, filters)
# We need to reshape it to (batch_size, time_steps, features) for the RNN
# time_steps will be the width of the feature maps after pooling
# features will be height * filters
shape_before_rnn = K.int_shape(x)
x = Reshape(target_shape=(shape_before_rnn[2], shape_before_rnn[1] * shape_before_rnn[3]))(x)

# Recurrent layers (RNN - Bidirectional LSTM)
# x = Bidirectional(LSTM(lstm_units, return_sequences=True, dropout=0.25))(x)
# x = Bidirectional(LSTM(lstm_units, return_sequences=True, dropout=0.25))(x)
      # dropout>0 menonaktifkan kernel cuDNN. Untuk memaksimalkan GPU:
      # set dropout=0.0 dan recurrent_dropout=0.0
      # biarkan activation='tanh' & recurrent_activation='sigmoid' (default)
      # unroll=False (default)
x = Bidirectional(tf.keras.layers.LSTM(
        128, return_sequences=True,
        dropout=0.0, recurrent_dropout=0.0
))(x)
x = Bidirectional(tf.keras.layers.LSTM(
        128, return_sequences=True,
        dropout=0.0, recurrent_dropout=0.0
))(x)


# Output layer
x = Dense(num_classes, activation='softmax', name='predictions')(x)

# Model definition
model = Model(inputs=input_tensor, outputs=x)


# CTC Loss function – TANPA slicing
# ganti dtypes ke int32
labels      = tf.keras.Input(name='labels', shape=(None,), dtype='int32')
input_length= tf.keras.Input(name='input_length', shape=(1,), dtype='int32')
label_length= tf.keras.Input(name='label_length', shape=(1,), dtype='int32')

def ctc_lambda_func(args):
    y_pred, labels_t, in_len, lab_len = args
    # jangan slicing y_pred
    return tf.keras.backend.ctc_batch_cost(labels_t, y_pred, in_len, lab_len)

ctc_loss_output = tf.keras.layers.Lambda(
    ctc_lambda_func, output_shape=(1,), name='ctc_loss', dtype='float32'  # pastikan loss float32
)([x, labels, input_length, label_length])

# Model with CTC loss
model_with_ctc = Model(inputs=[input_tensor, labels, input_length, label_length], outputs=ctc_loss_output)

# Compile the model
model_with_ctc.compile(loss={'ctc_loss': lambda y_true, y_pred: y_pred}, optimizer='adam')
# opt = tf.keras.optimizers.Adam(1e-3, clipnorm=5.0)
# model_with_ctc.compile(
#     loss={'ctc_loss': lambda y_true, y_pred: y_pred},
#     optimizer=opt,
#     # jit_compile=True,   # <<β€” aktifkan XLA (TF >= 2.9 / Keras 3)
#     jit_compile=False,   # <<β€” aktifkan XLA (TF >= 2.9 / Keras 3)
# )

model.summary()

from torchvision import transforms as T
from torchvision.transforms import InterpolationMode
import tensorflow as tf

# 1) Transform ke 50x250 (tanpa distorsi)
transform = transforms.Compose([
    transforms.Resize((50, 250), interpolation=InterpolationMode.BILINEAR, antialias=True),
    transforms.ToTensor(),
    transforms.Normalize((0.5,), (0.5,)),
])

CHARSET = list("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ")

# forward mapping: no UNK, no mask
char_to_num = tf.keras.layers.StringLookup(
    vocabulary=CHARSET,
    oov_token=None,
    mask_token=None,        # no mask
    num_oov_indices=0       # no UNK
)


# inverse mapping: JANGAN set oov_token
num_to_char = tf.keras.layers.StringLookup(
    vocabulary=CHARSET,  # pakai CHARSET langsung
    invert=True,
    num_oov_indices=0,   # penting
    mask_token=None,
)

print("vocab size:", len(char_to_num.get_vocabulary()))  # -> 36
print(char_to_num.get_vocabulary())                      # -> ['0','1',...,'Z']
print(num_to_char.get_vocabulary())                      # -> ['0','1',...,'Z']

class DataGenerator(tf.keras.utils.Sequence):
    def __init__(self, dataframe, char_to_num,
                 batch_size=32, img_width=250, img_height=50, max_label_length=5):
        self.dataframe = dataframe.reset_index(drop=True)
        self.char_to_num = char_to_num
        self.batch_size = batch_size
        self.img_width = img_width
        self.img_height = img_height
        self.max_label_length = max_label_length
        # time-steps setelah 3x MaxPool(2,2) di sumbu lebar
        self.time_steps = self.img_width // 8  # 250 // 8 = 31
        self.on_epoch_end()

    def __len__(self):
        return len(self.dataframe) // self.batch_size  # drop last

    def __getitem__(self, index):
        start_index = index * self.batch_size
        end_index = (index + 1) * self.batch_size
        batch_df = self.dataframe.iloc[start_index:end_index]

        images = []
        labels = []
        input_lengths = np.full((len(batch_df), 1), self.time_steps, dtype=np.int64)
        label_lengths = []

        for _, row in batch_df.iterrows():
            # 1) Load & preprocess image -> (H,W,1) float32
            img = Image.open(row.filepath).convert("L")
            t = transform(img)                          # torch tensor (1,H,W), normalized [-1,1]
            arr = t.permute(1, 2, 0).numpy()            # -> (H,W,1)
            images.append(arr)

            # 2) Encode label (UPPERCASE), pad -1, dtype int32
            lab = row.label.upper()
            lab_ids = self.char_to_num(tf.constant(list(lab))).numpy().astype(np.int32)
            pad_len = self.max_label_length - len(lab_ids)
            if pad_len < 0:
                lab_ids = lab_ids[:self.max_label_length]
                pad_len = 0
            lab_ids = np.pad(lab_ids, (0, pad_len), mode="constant", constant_values=-1)
            labels.append(lab_ids)

            # 3) label_length asli (tanpa padding)
            label_lengths.append([len(lab)])

        images = np.asarray(images, dtype=np.float32)               # (B,H,W,1)
        labels = np.asarray(labels, dtype=np.int32)                 # (B,L)
        label_lengths = np.asarray(label_lengths, dtype=np.int64)   # (B,1)

        inputs = {
            'input': images,
            'labels': labels,
            'input_length': input_lengths,
            'label_length': label_lengths
        }
        # dummy target; loss dihitung di Lambda
        outputs = np.zeros((images.shape[0],), dtype=np.float32)

        return inputs, outputs

    def on_epoch_end(self):
        self.dataframe = self.dataframe.sample(frac=1.0).reset_index(drop=True)

# Instantiate the data generators
train_generator = DataGenerator(train_df, char_to_num, batch_size=32, max_label_length=5)
val_generator = DataGenerator(val_df, char_to_num, batch_size=32, max_label_length=5)

import numpy as np
# cek isian
# ambil batch pertama
(inputs, outputs) = train_generator[0]

x      = inputs['input']          # (B, 50, 250, 1), float32, ~[-1,1]
y      = inputs['labels']         # (B, 5), int32, pad = -1
inlen  = inputs['input_length']   # (B, 1) == 31
lablen = inputs['label_length']   # (B, 1) == 5

print("x:", x.shape, x.dtype, x.min(), x.max())
print("labels:", y.shape, y.dtype, "unique pads:", sorted(set(y.flatten()) - set(range(0,36)))[:5])
print("input_length uniq:", set(inlen.flatten().tolist()))
print("label_length uniq:", set(lablen.flatten().tolist()))
print("outputs (dummy):", outputs.shape, outputs.dtype)

# assert sanity
assert x.shape[1:] == (50, 250, 1)
assert y.shape[1] == 5
assert inlen.min() == inlen.max() == 31
assert lablen.min() >= 1 and lablen.max() <= 5
assert y.dtype == np.int32

# CEK CTC DECODING
# 1) pastikan semua id label ada di rentang 0..35
assert y.min() >= 0 and y.max() <= 35, f"Label di luar rentang 0..35: min={y.min()}, max={y.max()}"

# 2) quick CTC loss test (harus finite, bukan NaN/Inf)
yp = model.predict(x[:4], verbose=0)  # (4, 31, 37)
loss = tf.keras.backend.ctc_batch_cost(y[:4], yp, inlen[:4], lablen[:4]).numpy()
print("CTC sample loss:", loss)  # cek semua np.isfinite(loss)
assert np.all(np.isfinite(loss)), f"CTC loss non-finite: {loss}"

# 3) (opsional) decode balik 3 label GT buat sanity check mapping
CHARSET = np.array(list("0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ"))
def decode_ids_row_np(ids_1d):
    ids_1d = [int(t) for t in ids_1d if int(t) >= 0]  # buang padding
    return "".join(CHARSET[ids_1d]) if ids_1d else ""

for i in range(3):
    print(i, "GT:", decode_ids_row_np(y[i]))



"""SIMPAN TIAP EPOCH"""

import os, re, glob
from pathlib import Path
import tensorflow as tf
from tensorflow.keras.callbacks import EarlyStopping, ModelCheckpoint

# ====== Paths ======
CKPT_DIR = Path("/workspace")
CKPT_DIR.mkdir(parents=True, exist_ok=True)

BEST_PATH   = CKPT_DIR / "captcha_best.weights.h5"
EPOCH_PATH  = CKPT_DIR / "captcha_ep{epoch:03d}.weights.h5"  # <-- setiap epoch

# ====== Callbacks ======
# 1) Simpan "best" berdasarkan val_loss
ckpt_best = ModelCheckpoint(
    filepath=str(BEST_PATH),
    monitor="val_loss",
    save_best_only=True,
    save_weights_only=True,
    save_freq="epoch",
    verbose=1,
)

# 2) Simpan SETIAP EPOCH
ckpt_every_epoch = ModelCheckpoint(
    filepath=str(EPOCH_PATH),
    save_best_only=False,          # <-- wajib False untuk setiap epoch
    save_weights_only=True,
    save_freq="epoch",             # defaultnya juga 'epoch', ini eksplisit saja
    verbose=0,
)

early_stopping = EarlyStopping(
    monitor="val_loss",
    patience=15,
    restore_best_weights=True,
    verbose=1,
)

# ====== Resume logic ======
def find_latest_epoch_ckpt(dir_path: Path):
    files = glob.glob(str(dir_path / "captcha_ep*.weights.h5"))
    if not files:
        return None, None
    pairs = []
    for f in files:
        m = re.search(r"captcha_ep(\d{3})\.weights\.h5$", os.path.basename(f))
        if m:
            pairs.append((int(m.group(1)), f))
    if not pairs:
        return None, None
    pairs.sort(key=lambda x: x[0])
    return pairs[-1]  # (epoch, path)

initial_epoch = 0
ep, last_path = find_latest_epoch_ckpt(CKPT_DIR)
if last_path:
    print(f"[RESUME] Loading weights from {last_path}")
    model_with_ctc.load_weights(last_path)
    initial_epoch = ep
    print(f"[RESUME] initial_epoch set to {initial_epoch}")
elif BEST_PATH.exists():
    print(f"[RESUME] Loading BEST weights from {BEST_PATH}")
    model_with_ctc.load_weights(str(BEST_PATH))
    initial_epoch = 0
else:
    print("[RESUME] No checkpoint found. Starting from scratch.")

# ====== Fit ======
history = model_with_ctc.fit(
    train_generator,
    validation_data=val_generator,
    epochs=100,                         # balikin ke target kamu
    # epochs=10,                         # balikin ke target kamu
    initial_epoch=initial_epoch,
    callbacks=[ckpt_best, ckpt_every_epoch, early_stopping],
    verbose=1,
)

# (Opsional) simpan bobot final & model inference
model_with_ctc.save_weights(str(CKPT_DIR / "captcha_final.weights.h5"))
model.save(str(CKPT_DIR / "captcha_final_model_base.h5"))   # model inference (tanpa Lambda CTC)
model.save(str(CKPT_DIR / "captcha_final_model_base.keras"))