import sys
import os
import re
import numpy as np
import torch
import soundfile as sf

from sentence_splitter import PersianSentenceSplitter
from persian_numbers import find_and_normalize_numbers


class GenerateSpeechPipe:
    def __init__(self, ref_wav_path=None, models_path=None, results_path=None, sample_path=None):
        # Set base paths
        BASE_DIR = os.path.dirname(os.path.abspath(__file__))
        self.models_path = models_path or os.path.join(BASE_DIR, 'saved_models', 'final_models')
        self.results_path = results_path or os.path.join(BASE_DIR, 'results')
        self.sample_path = sample_path or os.path.join(BASE_DIR, 'sample.wav')

        # Append pmt2 to sys.path for internal imports
        sys.path.append(os.path.join(BASE_DIR, 'pmt2'))

        # Initialize components
        self.encoder = None
        self.synthesizer = None
        self.vocoder = None
        self.sentence_splitter = None
        self.embed = None

        # Load models
        self._load_models(ref_wav_path)

    def _load_models(self, ref_wav_path=None):
        try:
            from encoder import inference as encoder_module
            from synthesizer.inference import Synthesizer
            from parallel_wavegan.utils import load_model as vocoder_hifigan

            self.encoder = encoder_module

            print("Loading encoder model...")
            self.encoder.load_model(os.path.join(self.models_path, 'encoder.pt'))

            print("Loading synthesizer model...")
            self.synthesizer = Synthesizer(os.path.join(self.models_path, 'synthesizer.pt'))

            print("Loading HiFiGAN vocoder...")
            self.vocoder = vocoder_hifigan(os.path.join(self.models_path, 'vocoder_HiFiGAN.pkl'))
            self.vocoder.remove_weight_norm()
            self.vocoder = self.vocoder.eval().to('cuda' if torch.cuda.is_available() else 'cpu')

            self.sentence_splitter = PersianSentenceSplitter(max_chars=150, min_chars=30)

            # Set reference audio path
            if ref_wav_path is None:
                ref_wav_path = self.sample_path

            print(f"Using reference audio: {ref_wav_path}")
            wav = self.synthesizer.load_preprocess_wav(ref_wav_path)
            encoder_wav = self.encoder.preprocess_wav(wav)
            self.embed, _, _ = self.encoder.embed_utterance(encoder_wav, return_partials=True)

            print("Models loaded successfully!")

        except Exception as e:
            import traceback
            print(f"Error loading models: {traceback.format_exc()}")
            raise RuntimeError("Failed to initialize GenerateSpeechPipe") from e

    def _normalize_text_for_synthesis(self, text: str) -> str:
        text = text.replace('ك', 'ک').replace('ي', 'ی')
        text = text.replace('_', '\u200c')
        text = re.sub(r'\s+', ' ', text).strip()
        text = find_and_normalize_numbers(text)
        return text

    def _synthesize_segment(self, text_segment: str, embed: np.ndarray) -> np.ndarray:
        try:
            text_segment = self._normalize_text_for_synthesis(text_segment)
            specs = self.synthesizer.synthesize_spectrograms([text_segment], [embed])
            spec = specs[0]

            x = torch.from_numpy(spec.T).to('cuda' if torch.cuda.is_available() else 'cpu')
            with torch.no_grad():
                wav = self.vocoder.inference(x)
            wav = wav.cpu().numpy().squeeze() if wav.ndim > 1 else wav
            return wav
        except Exception as e:
            import traceback
            print(f"Error synthesizing segment '{text_segment[:50]}...': {traceback.format_exc()}")
            return None

    def _add_silence(self, duration_ms: int = 300) -> np.ndarray:
        sample_rate = self.synthesizer.sample_rate
        num_samples = int(sample_rate * duration_ms / 1000)
        return np.zeros(num_samples, dtype=np.float32)

    def __call__(self, text, result_path=None, ref_wav_path=None, add_pauses: bool = True):
        if not text or not text.strip():
            return None

        try:
            # Use provided reference or default embed
            embed = self.embed
            if ref_wav_path is not None:
                print(f"Using alternative reference audio: {ref_wav_path}")
                wav = self.synthesizer.load_preprocess_wav(ref_wav_path)
                encoder_wav = self.encoder.preprocess_wav(wav)
                embed, _, _ = self.encoder.embed_utterance(encoder_wav, return_partials=True)

            # Split text
            text_segments = self.sentence_splitter.split(text)
            print(f"Split text into {len(text_segments)} segments:")
            for i, segment in enumerate(text_segments, 1):
                print(f"  Segment {i}: {segment[:60]}{'...' if len(segment) > 60 else ''}")

            # Synthesize each segment
            audio_segments = []
            silence = self._add_silence(300) if add_pauses else None

            for i, segment in enumerate(text_segments):
                print(f"Processing segment {i+1}/{len(text_segments)}...")
                segment_wav = self._synthesize_segment(segment, embed)
                if segment_wav is not None:
                    segment_wav = segment_wav.flatten() if segment_wav.ndim > 1 else segment_wav
                    audio_segments.append(segment_wav)
                    if add_pauses and i < len(text_segments) - 1:
                        audio_segments.append(silence)
                else:
                    print(f"Warning: Failed to synthesize segment {i+1}")

            if not audio_segments:
                print("Error: No audio segments were generated successfully")
                return None

            # Normalize and concatenate
            audio_segments = [seg.flatten() if seg.ndim > 1 else seg for seg in audio_segments]
            final_wav = np.concatenate(audio_segments)
            final_wav = final_wav / np.abs(final_wav).max() * 0.97

            # Determine output path
            if result_path is not None and result_path.endswith(".wav"):
                output_path = result_path
            else:
                print("Error: Result path must end with .wav")
                return None

            # Save audio
            sf.write(output_path, final_wav, self.synthesizer.sample_rate)
            duration = len(final_wav) / self.synthesizer.sample_rate
            print(f"✓ Successfully generated speech: {output_path}")
            print(f"  Total duration: {duration:.2f} seconds")
            return output_path

        except Exception as e:
            import traceback
            print(f"Error generating speech: {traceback.format_exc()}")
            return None