tts_service/functions/tts.py

import asyncio
import json
import logging
import math
import os
import time
from contextlib import suppress

import edge_tts
import gradio as gr
import httpx
import soundfile as sf

from ..utils import cache_path, env_str, seconds_to_ms
from ..voices import voice_manager

log = logging.getLogger(__name__)


# TTS
async def generate_speech_from_text(
    text: str,
    voice_name: str,
    rate: int = 0,
    progress=gr.Progress(),  # noqa: B008
) -> tuple[str, str]:
    def update_progress(pct, msg) -> None:
        log.debug("Progress: %.1f%%: %s", pct * 100, msg)
        progress(pct, msg)

    tts_start = -1.0
    rvc_start = -1.0
    ts0 = time.time()
    update_progress(0, "Starting...")
    voice = voice_manager.voices[voice_name]

    text = text.strip()
    output_tts_path = cache_path(voice.tts, "", rate, text, extension="mp3")
    text_ptr = 0
    tts_cached = os.path.exists(output_tts_path)
    if not tts_cached:
        log.info("Synthesizing %s chars into %s", len(text), output_tts_path)
        rates = f"+{rate}%" if rate >= 0 else f"{rate}%"
        communicate = edge_tts.Communicate(text, voice.tts, rate=rates)
        with open(output_tts_path, "wb") as f:
            async for chunk in communicate.stream():
                if tts_start < 0:
                    tts_start = time.time()

                chunk_type = chunk["type"]
                if chunk_type == "audio":
                    f.write(chunk["data"])
                elif chunk_type == "WordBoundary":
                    chunk_text = chunk["text"]
                    text_index = -1
                    with suppress(ValueError):
                        text_index = text.index(chunk_text, text_ptr)
                    if text_index == -1:
                        log.warning("Extraneous text received from edge tts: %s", chunk_text)
                        continue
                    text_ptr = text_index + len(chunk_text)
                    pct_complete = text_ptr / len(text)
                    log.debug("%.1f%%: %s", pct_complete * 100, chunk)
                    update_progress(pct_complete / 2, "Synthesizing...")
                else:
                    log.warning("Unknown chunk type: %s: %s", chunk_type, json.dumps(chunk))
    else:
        log.info("TTS cached at %s", output_tts_path)

    audio_duration = sf.info(output_tts_path).duration
    expected_processing_time = audio_duration / 10 + 20  # 10x real-time on nvidia t4

    ts1 = time.time()
    output_rvc_path = cache_path(voice.tts, voice.name, rate, text, extension="mp3")
    rvc_cached = os.path.exists(output_rvc_path)
    if not rvc_cached:
        log.info(
            "Converting %s of audio into %s. Expected duration: %s",
            seconds_to_ms(audio_duration),
            output_rvc_path,
            seconds_to_ms(expected_processing_time),
        )
        last_check = 0.0
        timeout = httpx.Timeout(5, read=60.0)
        endpoint_url = env_str("RVC_ENDPOINT")
        async with httpx.AsyncClient(timeout=timeout) as client:
            response = await client.post(f"{endpoint_url}/v1/rvc", content=output_tts_path.read_bytes())
            rvc_start = time.time()
            response.raise_for_status()
            data = response.json()
            log.info("Submitted for conversion: %s", data)
            result_url = data["urls"]["result"]
            while True:
                elapsed = time.time() - ts1
                rvc_elapsed = time.time() - rvc_start
                proportion = elapsed / expected_processing_time
                pct_complete = 0.5 + math.tanh(proportion) / 2
                update_progress(pct_complete, "Processing...")
                if rvc_elapsed > 0.8 * expected_processing_time and elapsed - last_check > 10:
                    last_check = elapsed
                    response = await client.get(result_url)
                    content_type = response.headers.get("Content-Type")
                    processed_bytes = await response.aread()
                    log.info(f"Checking status: %s (%s) {len(processed_bytes):,} bytes", response.status_code, content_type)
                    if response.status_code == 200 and content_type == "audio/mpeg":
                        output_rvc_path.write_bytes(processed_bytes)
                        break
                    elif response.status_code != 404:
                        response.raise_for_status()
                await asyncio.sleep(0.1)
        log.info("Successfully converted text (%s chars) -> %s", len(text), output_rvc_path)
    else:
        log.info("Already converted: %s", output_rvc_path)

    def format_duration(duration: float) -> str:
        return "Cached" if duration < 1 else seconds_to_ms(duration)

    def format_wpm(duration: float) -> str:
        return "Cached" if duration < 1 else f"{word_count * 60 / duration:,.0f}"

    def format_rate(duration: float) -> str:
        return "Cached" if duration < 1 else f"{audio_duration / duration:.1f}x"

    def format_latency(latency: float) -> str:
        return "N/A" if latency < 1 else f"{latency:.2f}s"

    ts2 = time.time()
    total_time = ts2 - ts0
    rvc_time = ts2 - rvc_start if rvc_start > 0 else 0
    tts_time = ts1 - tts_start if tts_start > 0 else 0
    word_count = len(text.split())
    durations = (audio_duration, total_time, tts_time, rvc_time)
    times = " | ".join(format_duration(t) for t in durations)
    wpms = " | ".join(format_wpm(t) for t in durations)
    rates = " | ".join(format_rate(t) for t in durations)
    latencies = " | ".join(format_latency(latency) for latency in (0, 0, tts_start - ts0, rvc_start - ts1))
    rvc_cost = "N/A" if rvc_cached else f"{rvc_time * 0.0164:.1f}¢"
    markdown_status = f"""
Audio successfully synthesized.

|     | Words | Chars | Cost |
|-----|------:|------:|-----:|
|Count|{word_count:,}|{len(text):,}|{rvc_cost}|

|     |Actual|Processing|TTS|RVC|
|-----|-----:|---------:|--:|--:|
|Time|{times}|
|WPM|{wpms}|
|Rate|{rates}|
|Latency|{latencies}|

""".strip()
    log.info(markdown_status)
    return markdown_status, str(output_rvc_path)