modules/dna_module.py

import copy
import math
from collections import defaultdict

import PIL
import numpy as np
import pandas as pd
import torch, time, os
import wandb
import seaborn as sns
import yaml

sns.set_style('whitegrid')
from matplotlib import pyplot as plt
from torch import optim

from models.dna_models import MLPModel, CNNModel, TransformerModel, DeepFlyBrainModel
from utils.flow_utils import DirichletConditionalFlow, expand_simplex, sample_cond_prob_path, simplex_proj, \
    get_wasserstein_dist, update_ema, load_flybrain_designed_seqs
from modules.general_module import GeneralModule
from utils.log import get_logger

from flow_matching.path import MixtureDiscreteProbPath
from flow_matching.path.scheduler import PolynomialConvexScheduler
from flow_matching.solver import MixtureDiscreteEulerSolver
from flow_matching.utils import ModelWrapper
from flow_matching.loss import MixturePathGeneralizedKL

import pdb


logger = get_logger(__name__)


class DNAModule(GeneralModule):
    def __init__(self, args, alphabet_size, num_cls, source_distribution="uniform"):
        super().__init__(args)
        self.alphabet_size = alphabet_size
        self.source_distribution = source_distribution
        self.epsilon = 1e-3

        if source_distribution == "uniform":
            added_token = 0
        elif source_distribution == "mask":
            self.mask_token = alphabet_size  # tokens starting from zero
            added_token = 1
        else:
            raise NotImplementedError
        self.alphabet_size += added_token

        self.load_model(self.alphabet_size, num_cls)

        self.scheduler = PolynomialConvexScheduler(n=args.scheduler_n)
        self.path = MixtureDiscreteProbPath(scheduler=self.scheduler)
        self.loss_fn = MixturePathGeneralizedKL(path=self.path)

        self.val_outputs = defaultdict(list)
        self.train_outputs = defaultdict(list)
        self.train_out_initialized = False
        self.mean_log_ema = {}
        if self.args.taskiran_seq_path is not None:
            self.taskiran_fly_seqs = load_flybrain_designed_seqs(self.args.taskiran_seq_path).to(self.device)

    def on_load_checkpoint(self, checkpoint):
        checkpoint['state_dict'] = {k: v for k,v in checkpoint['state_dict'].items() if 'cls_model' not in k and 'distill_model' not in k}

    def training_step(self, batch, batch_idx):
        self.stage = 'train'
        loss = self.general_step(batch, batch_idx)
        if self.args.ckpt_iterations is not None and self.trainer.global_step in self.args.ckpt_iterations:
            self.trainer.save_checkpoint(os.path.join(os.environ["MODEL_DIR"],f"epoch={self.trainer.current_epoch}-step={self.trainer.global_step}.ckpt"))
        # self.try_print_log()
        return loss

    def validation_step(self, batch, batch_idx):
        self.stage = 'val'
        loss = self.general_step(batch, batch_idx)
        # if self.args.validate:
        #     self.try_print_log()

    def general_step(self, batch, batch_idx=None):
        self.iter_step += 1
        x_1, cls = batch
        B, L = x_1.shape
        x_1 = x_1.to(self.device)

        if self.source_distribution == "uniform":
            x_0 = torch.randint_like(x_1, high=self.alphabet_size)
        elif self.source_distribution == "mask":
            x_0 = torch.zeros_like(x_1) + self.mask_token
        else:
            raise NotImplementedError
        # pdb.set_trace()
        t = torch.rand(x_1.shape[0]) * (1 - self.epsilon)
        t = t.to(x_1.device)
        path_sample = self.path.sample(t=t, x_0=x_0, x_1=x_1)

        logits = self.model(x_t=path_sample.x_t, t=path_sample.t)
        loss = self.loss_fn(logits=logits, x_1=x_1, x_t=path_sample.x_t, t=path_sample.t)
        # pdb.set_trace()

        self.lg('loss', loss)
        if self.stage == "val":
            predicted = logits.argmax(dim=-1)
            accuracy = (predicted == x_1).float().mean()
            self.lg('acc', accuracy)
        self.last_log_time = time.time()
        return loss

    @torch.no_grad()
    def dirichlet_flow_inference(self, seq, cls, model, args):
        B, L = seq.shape
        K = model.alphabet_size
        x0 = torch.distributions.Dirichlet(torch.ones(B, L, model.alphabet_size, device=seq.device)).sample()
        eye = torch.eye(K).to(x0)
        xt = x0.clone()

        t_span = torch.linspace(1, args.alpha_max, self.args.num_integration_steps, device=self.device)
        for i, (s, t) in enumerate(zip(t_span[:-1], t_span[1:])):
            xt_expanded, prior_weights = expand_simplex(xt, s[None].expand(B), args.prior_pseudocount)

            logits = model(xt_expanded, t=s[None].expand(B))
            flow_probs = torch.nn.functional.softmax(logits / args.flow_temp, -1) # [B, L, K]

            if not torch.allclose(flow_probs.sum(2), torch.ones((B, L), device=self.device), atol=1e-4) or not (flow_probs >= 0).all():
                print(f'WARNING: flow_probs.min(): {flow_probs.min()}. Some values of flow_probs do not lie on the simplex. There are we are {(flow_probs<0).sum()} negative values in flow_probs of shape {flow_probs.shape} that are negative. We are projecting them onto the simplex.')
                flow_probs = simplex_proj(flow_probs)

            c_factor = self.condflow.c_factor(xt.cpu().numpy(), s.item())
            c_factor = torch.from_numpy(c_factor).to(xt)

            self.inf_counter += 1

            if not (flow_probs >= 0).all(): print(f'flow_probs.min(): {flow_probs.min()}')
            cond_flows = (eye - xt.unsqueeze(-1)) * c_factor.unsqueeze(-2)
            flow = (flow_probs.unsqueeze(-2) * cond_flows).sum(-1)

            xt = xt + flow * (t - s)

            if not torch.allclose(xt.sum(2), torch.ones((B, L), device=self.device), atol=1e-4) or not (xt >= 0).all():
                print(f'WARNING: xt.min(): {xt.min()}. Some values of xt do not lie on the simplex. There are we are {(xt<0).sum()} negative values in xt of shape {xt.shape} that are negative. We are projecting them onto the simplex.')
                xt = simplex_proj(xt)
        return logits, x0

    def on_validation_epoch_start(self):
        self.inf_counter = 1
        self.nan_inf_counter = 0

    def on_validation_epoch_end(self):
        self.generator = np.random.default_rng()
        log = self._log
        log = {key: log[key] for key in log if "val_" in key}
        log = self.gather_log(log, self.trainer.world_size)
        mean_log = self.get_log_mean(log)
        mean_log.update({'val_nan_inf_step_fraction': self.nan_inf_counter / self.inf_counter})

        mean_log.update({'epoch': float(self.trainer.current_epoch), 'step': float(self.trainer.global_step), 'iter_step': float(self.iter_step)})

        self.mean_log_ema = update_ema(current_dict=mean_log, prev_ema=self.mean_log_ema, gamma=0.9)
        mean_log.update(self.mean_log_ema)
        if self.trainer.is_global_zero:
            logger.info(str(mean_log))
            self.log_dict(mean_log, batch_size=1)
            if self.args.wandb:
                wandb.log(mean_log)

            path = os.path.join(os.environ["MODEL_DIR"], f"val_{self.trainer.global_step}.csv")
            pd.DataFrame(log).to_csv(path)

        for key in list(log.keys()):
            if "val_" in key:
                del self._log[key]
        self.val_outputs = defaultdict(list)


    def on_train_epoch_start(self) -> None:
        self.inf_counter = 1
        self.nan_inf_counter = 0
        # if not self.loaded_distill_model and self.args.distill_ckpt is not None:
        #     self.load_distill_model()
        #     self.loaded_distill_model = True
        # if not self.loaded_classifiers:
        #     self.load_classifiers(load_cls=self.args.cls_ckpt is not None, load_clean_cls=self.args.clean_cls_ckpt is not None)
        #     self.loaded_classifiers = True

    def on_train_epoch_end(self):
        self.train_out_initialized = True
        log = self._log
        log = {key: log[key] for key in log if "train_" in key}
        log = self.gather_log(log, self.trainer.world_size)
        mean_log = self.get_log_mean(log)
        mean_log.update(
            {'epoch': float(self.trainer.current_epoch), 'step': float(self.trainer.global_step), 'iter_step': float(self.iter_step)})

        if self.trainer.is_global_zero:
            logger.info(str(mean_log))
            self.log_dict(mean_log, batch_size=1)
            if self.args.wandb:
                wandb.log(mean_log)

        for key in list(log.keys()):
            if "train_" in key:
                del self._log[key]

    def lg(self, key, data):
        if isinstance(data, torch.Tensor):
            data = data.detach().cpu().numpy()
        log = self._log
        if self.args.validate or self.stage == 'train':
            log["iter_" + key].append(data)
        log[self.stage + "_" + key].append(data)

    def configure_optimizers(self):
        optimizer = optim.Adam(self.parameters(), lr=self.args.lr)
        return optimizer

    def plot_empirical_and_true(self, empirical_dist, true_dist):
        num_datasets_to_plot = min(4, empirical_dist.shape[0])
        width = 1
        # Creating a figure and axes
        fig, axes = plt.subplots(math.ceil(num_datasets_to_plot/2), 2, figsize=(10, 8))
        for i in range(num_datasets_to_plot):
            row, col = i // 2, i % 2
            x = np.arange(len(empirical_dist[i]))
            axes[row, col].bar(x, empirical_dist[i], width, label=f'empirical')
            axes[row, col].plot(x, true_dist[i], label=f'true density', color='orange')
            axes[row, col].legend()
            axes[row, col].set_title(f'Sequence position {i + 1}')
            axes[row, col].set_xlabel('Category')
            axes[row, col].set_ylabel('Density')
        plt.tight_layout()
        fig.canvas.draw()
        pil_img = PIL.Image.frombytes('RGB', fig.canvas.get_width_height(), fig.canvas.tostring_rgb())
        plt.close()
        return pil_img

    def load_model(self, alphabet_size, num_cls):
        if self.args.model == 'cnn':
            self.model = CNNModel(self.args, alphabet_size=alphabet_size)
        elif self.args.model == 'mlp':
            self.model = MLPModel(input_dim=alphabet_size, time_dim=1, hidden_dim=self.args.hidden_dim, length=self.args.length)
        elif self.args.model == 'transformer':
            self.model = TransformerModel(alphabet_size=alphabet_size, seq_length=self.args.length, embed_dim=self.args.hidden_dim, \
                                          num_layers=self.args.num_layers, num_heads=self.args.num_heads, dropout=self.args.dropout)
        elif self.args.model == 'deepflybrain':
            self.model = DeepFlyBrainModel(self.args, alphabet_size=alphabet_size,num_cls=num_cls)
        else:
            raise NotImplementedError()

    def plot_score_and_probs(self):
        clss = torch.cat(self.val_outputs['clss_noisycls'])
        probs = torch.softmax(torch.cat(self.val_outputs['logits_noisycls']), dim=-1)
        scores = torch.cat(self.val_outputs['scores_noisycls']).cpu().numpy()
        score_norms = np.linalg.norm(scores, axis=-1)
        alphas = torch.cat(self.val_outputs['alphas_noisycls']).cpu().numpy()
        true_probs = probs[torch.arange(len(probs)), clss].cpu().numpy()
        bins = np.linspace(min(alphas), 12, 20)
        indices = np.digitize(alphas, bins)
        bin_means = [np.mean(true_probs[indices == i]) for i in range(1, len(bins))]
        bin_std = [np.std(true_probs[indices == i]) for i in range(1, len(bins))]
        bin_centers = 0.5 * (bins[:-1] + bins[1:])

        bin_pos_std = [np.std(true_probs[indices == i][true_probs[indices == i] > np.mean(true_probs[indices == i])]) for i in range(1, len(bins))]
        bin_neg_std = [np.std(true_probs[indices == i][true_probs[indices == i] < np.mean(true_probs[indices == i])]) for i in range(1, len(bins))]
        plot_data = pd.DataFrame({'Alphas': bin_centers, 'Means': bin_means, 'Std': bin_std, 'Pos_Std': bin_pos_std, 'Neg_Std': bin_neg_std})
        plt.figure(figsize=(10, 6))
        sns.lineplot(x='Alphas', y='Means', data=plot_data)
        plt.fill_between(plot_data['Alphas'], plot_data['Means'] - plot_data['Neg_Std'], plot_data['Means'] + plot_data['Pos_Std'], alpha=0.3)
        plt.xlabel('Binned alphas values')
        plt.ylabel('Mean of predicted probs for true class')
        fig = plt.gcf()
        fig.canvas.draw()
        pil_probs = PIL.Image.frombytes('RGB', fig.canvas.get_width_height(), fig.canvas.tostring_rgb())

        plt.close()
        bin_means = [np.mean(score_norms[indices == i]) for i in range(1, len(bins))]
        bin_std = [np.std(score_norms[indices == i]) for i in range(1, len(bins))]
        bin_pos_std = [np.std(score_norms[indices == i][score_norms[indices == i] > np.mean(score_norms[indices == i])]) for i in range(1, len(bins))]
        bin_neg_std = [np.std(score_norms[indices == i][score_norms[indices == i] < np.mean(score_norms[indices == i])]) for i in range(1, len(bins))]
        plot_data = pd.DataFrame({'Alphas': bin_centers, 'Means': bin_means, 'Std': bin_std, 'Pos_Std': bin_pos_std, 'Neg_Std': bin_neg_std})
        plt.figure(figsize=(10, 6))
        sns.lineplot(x='Alphas', y='Means', data=plot_data)
        plt.fill_between(plot_data['Alphas'], plot_data['Means'] - plot_data['Neg_Std'],
                         plot_data['Means'] + plot_data['Pos_Std'], alpha=0.3)
        plt.xlabel('Binned alphas values')
        plt.ylabel('Mean of norm of the scores')
        fig = plt.gcf()
        fig.canvas.draw()
        pil_score_norms = PIL.Image.frombytes('RGB', fig.canvas.get_width_height(), fig.canvas.tostring_rgb())
        return pil_probs, pil_score_norms

    def log_data_similarities(self, seq_pred):
        similarities1 = seq_pred.cpu()[:, None, :].eq(self.toy_data.data_class1[None, :, :])  # batchsize, dataset_size, seq_len
        similarities2 = seq_pred.cpu()[:, None, :].eq(self.toy_data.data_class2[None, :, :])  # batchsize, dataset_size, seq_len
        similarities = seq_pred.cpu()[:, None, :].eq(torch.cat([self.toy_data.data_class2[None, :, :], self.toy_data.data_class1[None, :, :]],dim=1))  # batchsize, dataset_size, seq_len
        self.lg('data1_sim', similarities1.float().mean(-1).max(-1)[0])
        self.lg('data2_sim', similarities2.float().mean(-1).max(-1)[0])
        self.lg('data_sim', similarities.float().mean(-1).max(-1)[0])
        self.lg('mean_data1_sim', similarities1.float().mean(-1).mean(-1))
        self.lg('mean_data2_sim', similarities2.float().mean(-1).mean(-1))
        self.lg('mean_data_sim', similarities.float().mean(-1).mean(-1))