import openai
from flask import Flask, jsonify, request, send_from_directory, send_file, Blueprint, current_app, url_for
import os
from flask_cors import CORS
import io  # for streaming S3 bytes in HF/AWS mode

# Optional (only used in AWS mode)
try:
    import boto3
    from botocore.exceptions import BotoCoreError, ClientError
except Exception:
    # Not required for local; will be imported dynamically in AWS mode
    boto3 = None
    BotoCoreError = ClientError = Exception

app = Flask(__name__)
CORS(app)

# --- Blueprint ---
finding_bp = Blueprint("findingword", __name__)

# Directories for video, audio, and transcripts
VIDEO_FOLDER = 'static/videos'
AUDIO_FOLDER = 'static/audio'   # used only in local mode
TRANSCRIPT_FOLDER = 'static/transcripts'

# --- OpenAI key handling (same as vocab builder) ---
_OPENAI_API_KEY_FALLBACK = os.getenv("OPENAI_API_KEY", "")

def _ensure_openai_key():
    """Set openai.api_key from Flask config or env before each API call."""
    api_key = (current_app.config.get("OPENAI_API_KEY") if current_app else None) or _OPENAI_API_KEY_FALLBACK
    if api_key:
        openai.api_key = api_key

# ---------------------- audio-mode helpers ----------------------
def _is_aws_mode() -> bool:
    """
    Switch to AWS Polly + S3 on Hugging Face / prod.
    Local stays on Google TTS + disk.
    """
    if os.getenv("USE_AWS_AUDIO", "0") == "1":
        return True
    if os.getenv("SPACE_ID"):  # set on Hugging Face Spaces
        return True
    if os.getenv("ENV", "dev").lower() == "prod":
        return True
    return False

def _sanitize_filename(word: str) -> str:
    # Keep your current style but ensure safe S3 key/filename
    return word.strip().replace(" ", "_").replace(".", "").lower()

# ---------------------------------------------------------------------

@finding_bp.route('/generate-vocabulary', methods=['GET'])
def get_vocabulary_word_from_openai():
    prompt = (
        "Pick a simple vocabulary word suitable for children (ages 6–8) "
        "and provide its meaning in very easy English. Do not repeat words from previous responses. "
        "Format: 'Word: [word]. Meaning: [meaning].'"
    )

    try:
        _ensure_openai_key()
        response = openai.chat.completions.create(
            model="gpt-3.5-turbo",
            messages=[
                {"role": "system", "content": "You are a helpful assistant."},
                {"role": "user", "content": prompt},
            ]
        )

        result = response.choices[0].message.content.strip()
        print(f"Full Response: {result}")

        if "Word:" in result and "Meaning:" in result:
            parts = result.split("Meaning:")
            word = parts[0].replace("Word:", "").strip()
            word = word.rstrip('.')  # avoid trailing dot
            meaning = parts[1].strip()

            # Generate the sentence
            sentence = generate_sentence(word, meaning)

            # Generate audio file for the vocabulary word
            audio_file_path_or_name = generate_audio(word)  # local path or just filename in AWS mode

            # URL for frontend remains identical
            # audio_url = f"/static/audio/{os.path.basename(audio_file_path_or_name)}"
            audio_url = url_for("findingword.serve_audio",
                    filename=os.path.basename(audio_file_path_or_name))

            return jsonify({
                "word": word,
                "meaning": meaning,
                "sentence": sentence,
                "audio_file_path": audio_url
            })

        else:
            return jsonify({"response": result, "message": "Meaning not provided in the expected format"})

    except Exception as e:
        return jsonify({"error": str(e)}), 500


def generate_sentence(word, meaning):
    prompt = f"Create a sentence using the word '{word}' that fully demonstrates its meaning: {meaning}"
    _ensure_openai_key()
    response = openai.chat.completions.create(
        model="gpt-3.5-turbo",
        messages=[
            {"role": "system", "content": "You are a helpful assistant."},
            {"role": "user", "content": prompt},
        ]
    )
    sentence = response.choices[0].message.content.strip()
    return sentence


def generate_audio(word):
    """
    Local (default): Google TTS → write MP3 to ./static/audio/<word>.mp3 → return full path.
    Hugging Face / AWS mode: Polly → upload to S3 (findingword/<word>.mp3) → return just the filename,
    and let /static/audio/<filename> stream from S3 (see route below).
    """
    sanitized_word = _sanitize_filename(word)
    filename = f"{sanitized_word}.mp3"

    if _is_aws_mode():
        # ---- AWS Polly + S3 path (no local write) ----
        if boto3 is None:
            raise RuntimeError("boto3 is required in AWS audio mode but not available")

        region = os.getenv("AWS_DEFAULT_REGION", "eu-north-1")
        bucket = os.getenv("S3_BUCKET_NAME")
        if not bucket:
            raise RuntimeError("S3_BUCKET_NAME is not set")

        polly = boto3.client("polly", region_name=region)
        s3 = boto3.client("s3", region_name=region)

        try:
            resp = polly.synthesize_speech(
                Text=word,
                OutputFormat="mp3",
                VoiceId=os.getenv("POLLY_VOICE_ID", "Joanna"),
                Engine=os.getenv("POLLY_ENGINE", "standard"),
                LanguageCode="en-US",
            )
            stream = resp.get("AudioStream")
            if not stream:
                raise RuntimeError("Polly returned no AudioStream")
            audio_bytes = stream.read()
        except (BotoCoreError, ClientError, Exception) as e:
            raise RuntimeError(f"Polly TTS failed: {e}")

        key = f"findingword/{filename}"
        try:
            s3.put_object(Bucket=bucket, Key=key, Body=audio_bytes, ContentType="audio/mpeg")
        except (BotoCoreError, ClientError, Exception) as e:
            raise RuntimeError(f"S3 upload failed: {e}")

        # Return only the filename; /static/audio/<filename> will proxy from S3
        return filename

    # ---- Local Google TTS path (lazy import; create dir here only) ----
    audio_dir = AUDIO_FOLDER
    try:
        os.makedirs(audio_dir, exist_ok=True)
    except Exception:
        # Fallback if CWD is restricted
        audio_dir = "/tmp/audio"
        os.makedirs(audio_dir, exist_ok=True)

    audio_file_path = os.path.join(audio_dir, filename)

    if not os.path.exists(audio_file_path):
        try:
            # Import only in local mode to avoid HF credential errors
            from google.cloud import texttospeech
            gcp_client = texttospeech.TextToSpeechClient()
        except Exception as e:
            raise RuntimeError(
                "Google TTS is required in local mode but missing. "
                "Install google-cloud-texttospeech and set GOOGLE_APPLICATION_CREDENTIALS. "
                f"Details: {e}"
            )

        synthesis_input = texttospeech.SynthesisInput(text=word)
        voice = texttospeech.VoiceSelectionParams(
            language_code="en-US", ssml_gender=texttospeech.SsmlVoiceGender.NEUTRAL
        )
        audio_config = texttospeech.AudioConfig(audio_encoding=texttospeech.AudioEncoding.MP3)

        response = gcp_client.synthesize_speech(
            input=synthesis_input, voice=voice, audio_config=audio_config
        )

        with open(audio_file_path, "wb") as out:
            out.write(response.audio_content)

        print(f"✅ Audio saved: {audio_file_path}")

    return audio_file_path


@finding_bp.route('/validate-word', methods=['POST'])
def validate_word():
    try:
        data = request.get_json()
        print("📥 Received data for validation:", data)

        if not data or 'user_input' not in data or 'correct_word' not in data:
            return jsonify({"error": "Invalid request, missing fields"}), 400

        user_input = data.get('user_input', '').strip()
        correct_word = data.get('correct_word', '').strip()

        if user_input.lower() == correct_word.lower():
            return jsonify({"status": "success", "message": "Correct! You typed the word correctly."})
        else:
            return jsonify({"status": "failure", "message": f"Incorrect. The correct word was '{correct_word}'."})

    except Exception as e:
        return jsonify({"error": str(e)}), 500


@finding_bp.route('/static/audio/<filename>')
def serve_audio(filename):
    """
    Local: serve from disk.
    AWS mode (HF): fetch the object from S3 and stream it (no local storage).
    """
    if _is_aws_mode():
        if boto3 is None:
            return jsonify({"error": "boto3 missing in AWS mode"}), 500

        region = os.getenv("AWS_DEFAULT_REGION", "eu-north-1")
        bucket = os.getenv("S3_BUCKET_NAME")
        if not bucket:
            return jsonify({"error": "S3_BUCKET_NAME not set"}), 500

        s3 = boto3.client("s3", region_name=region)
        key = f"findingword/{filename}"

        try:
            obj = s3.get_object(Bucket=bucket, Key=key)
            data = obj["Body"].read()
            return send_file(
                io.BytesIO(data),
                mimetype="audio/mpeg",
                download_name=filename,
                as_attachment=False
            )
        except (BotoCoreError, ClientError, Exception) as e:
            return jsonify({"error": f"S3 fetch failed: {str(e)}"}), 404

    # Local: serve file from disk as before (with /tmp fallback)
    local_path = os.path.join(AUDIO_FOLDER, filename)
    if os.path.exists(local_path):
        return send_from_directory(AUDIO_FOLDER, filename)

    alt_dir = "/tmp/audio"
    alt_path = os.path.join(alt_dir, filename)
    if os.path.exists(alt_path):
        return send_from_directory(alt_dir, filename)

    return jsonify({"error": "File not found"}), 404


# Run the Flask server (local dev): keep URLs unchanged by registering with empty prefix
if __name__ == '__main__':
    app.register_blueprint(finding_bp, url_prefix='')  # Local: /generate-vocabulary, /validate-word, /static/audio/...
    app.run(host='0.0.0.0', port=5005, debug=True)