import torch
import json
import torch.distributed as dist
import numpy as np
import kaldiio
import librosa



def load_audio(audio_path: str, fs: int=16000):
	audio = None
	if audio_path.startswith("oss:"):
		pass
	elif audio_path.startswith("odps:"):
		pass
	else:
		if ".ark:" in audio_path:
			audio = kaldiio.load_mat(audio_path)
		else:
			audio, fs = librosa.load(audio_path, sr=fs)
	return audio

def extract_features(data, date_type: str="sound", frontend=None):
	if date_type == "sound":
		feat, feats_lens = frontend(data, len(data))
		feat = feat[0, :, :]
	else:
		feat, feats_lens = torch.from_numpy(data).to(torch.float32), torch.tensor([data.shape[0]]).to(torch.int32)
	return feat, feats_lens
	
	

class IndexedDatasetJsonl(torch.utils.data.Dataset):
	
	def __init__(self, path):
		super().__init__()
		# data_parallel_size = dist.get_world_size()
		data_parallel_size = 1
		contents = []
		with open(path, encoding='utf-8') as fin:
			for line in fin:
				data = json.loads(line.strip())
				if "text" in data:  # for sft
					self.contents.append(data['text'])
				if "source" in data:  # for speech lab pretrain
					prompt = data["prompt"]
					source = data["source"]
					target = data["target"]
					source_len = data["source_len"]
					target_len = data["target_len"]

					contents.append({"source": source,
					                 "prompt": prompt,
					                 "target": target,
					                 "source_len": source_len,
					                 "target_len": target_len,
					                 }
					                )
		
		self.contents = []
		total_num = len(contents)
		num_per_rank = total_num // data_parallel_size
		# rank = dist.get_rank()
		rank = 0
		# import ipdb; ipdb.set_trace()
		self.contents = contents[rank * num_per_rank:(rank + 1) * num_per_rank]


	def __len__(self):
		return len(self.contents)
	
	def __getitem__(self, index):
		return self.contents[index]


class AudioDataset(torch.utils.data.Dataset):
	def __init__(self, path, frontend=None, tokenizer=None):
		super().__init__()
		self.indexed_dataset = IndexedDatasetJsonl(path)
		self.frontend = frontend.forward
		self.fs = 16000 if frontend is None else frontend.fs
		self.data_type = "sound"
		self.tokenizer = tokenizer
		self.int_pad_value = -1
		self.float_pad_value = 0.0

	

	
	def __len__(self):
		return len(self.indexed_dataset)
	
	def __getitem__(self, index):
		item = self.indexed_dataset[index]
		source = item["source"]
		data_src = load_audio(source, fs=self.fs)
		speech, speech_lengths = extract_features(data_src, self.data_type, self.frontend)
		target = item["target"]
		text = self.tokenizer.encode(target)
		text_lengths = len(text)
		text, text_lengths = torch.tensor(text, dtype=torch.int64), torch.tensor([text_lengths], dtype=torch.int32)
		return {"speech": speech,
		        "speech_lengths": speech_lengths,
		        "text": text,
		        "text_lengths": text_lengths,
		        }
	
	
	def collator(self, samples: list=None):
		
		outputs = {}
		for sample in samples:
			for key in sample.keys():
				if key not in outputs:
					outputs[key] = []
				outputs[key].append(sample[key])
		
		for key, data_list in outputs.items():
			if data_list[0].dtype.kind == "i":
				pad_value = self.int_pad_value
			else:
				pad_value = self.float_pad_value
			outputs[key] = torch.nn.utils.rnn.pad_sequence(data_list, batch_first=True, padding_value=pad_value)
		return samples