# StyleTTS 2 HTTP Streaming API by @fakerybakery - Copyright (c) 2023 mrfakename. All rights reserved.
# Docs: API_DOCS.md
# To-Do:
# * Support voice cloning
# * Implement authentication, user "credits" system w/ SQLite3
import io
import markdown
from tortoise.utils.text import split_and_recombine_text
from flask import Flask, Response, request, jsonify
import numpy as np
import ljinference
import torch
import hashlib
from scipy.io.wavfile import read, write
from flask_cors import CORS
import os
import torchaudio

def genHeader(sampleRate, bitsPerSample, channels):
    datasize = 2000 * 10**6
    o = bytes("RIFF", "ascii")
    o += (datasize + 36).to_bytes(4, "little")
    o += bytes("WAVE", "ascii")
    o += bytes("fmt ", "ascii")
    o += (16).to_bytes(4, "little")
    o += (1).to_bytes(2, "little")
    o += (channels).to_bytes(2, "little")
    o += (sampleRate).to_bytes(4, "little")
    o += (sampleRate * channels * bitsPerSample // 8).to_bytes(4, "little")
    o += (channels * bitsPerSample // 8).to_bytes(2, "little")
    o += (bitsPerSample).to_bytes(2, "little")
    o += bytes("data", "ascii")
    o += (datasize).to_bytes(4, "little")
    return o

import phonemizer
global_phonemizer = phonemizer.backend.EspeakBackend(language='en-us', preserve_punctuation=True,  with_stress=True)
print("Starting Flask app")

app = Flask(__name__)
cors = CORS(app)

@app.route("/")
def index():
    with open('API_DOCS.md', 'r') as f:
        return markdown.markdown(f.read())

cache_dir = 'cache'
if not os.path.exists(cache_dir):
    os.makedirs(cache_dir, exist_ok=True)

@app.route("/api", methods=['GET', 'POST'])
def serve_wav():
    if request.method == 'GET':
        request.form = request.args
    if 'text' not in request.form:
        if 'text' not in request.json:
            error_response = {'error': 'Missing required fields. Please include "text" in your request.'}
            return jsonify(error_response), 400
        else:
            text = request.json['text']
    else:
        text = request.form['text'].strip()
    if not text.strip():
        error_response = {'error': 'Empty text. Please ensure "text" in not empty.'}
        return jsonify(error_response), 400
    texts = split_and_recombine_text(text)
    audios = []
    noise = torch.randn(1,1,256).to('cuda' if torch.cuda.is_available() else 'cpu')
    for t in texts:
        # check for cache
        hash = hashlib.sha256(t.lower().encode()).hexdigest()
        if os.path.exists(os.path.join(cache_dir, hash + '.wav')):
            audios.append(read(os.path.join(cache_dir, hash + '.wav'))[1])
        else:
            aud = ljinference.inference(t, noise, diffusion_steps=7, embedding_scale=1)
            write(os.path.join(cache_dir, hash + '.wav'), 24000, aud)
            audios.append(aud)
    output_buffer = io.BytesIO()
    write(output_buffer, 24000, np.concatenate(audios))
    response = Response(output_buffer.getvalue())
    response.headers["Content-Type"] = "audio/wav"
    return response
if __name__ == "__main__":
    app.run("0.0.0.0", port=7860)