app.py

from fastapi import FastAPI, HTTPException, UploadFile, File, Form, Depends
from typing import Optional
from fastapi.responses import StreamingResponse, JSONResponse, HTMLResponse
from fastapi.staticfiles import StaticFiles
from fastapi.templating import Jinja2Templates
from huggingface_hub import InferenceClient
from pydantic import BaseModel, ConfigDict
import os
from base64 import b64encode
from io import BytesIO
from PIL import Image, ImageEnhance
import logging
import pytesseract
import time
import subprocess
subprocess.Popen(["python", "main.py"])
# Set Tesseract CMD path for Windows
#pytesseract.pytesseract.tesseract_cmd = r"F:\Python-files\tesseract\tesseract.exe"

app = FastAPI()

# Configure logging
logging.basicConfig(level=logging.DEBUG)
logger = logging.getLogger(__name__)


# Default model
DEFAULT_MODEL = "meta-llama/Meta-Llama-3-8B-Instruct"

# Initialize Jinja2 templates
templates = Jinja2Templates(directory="templates")

class TextRequest(BaseModel):
    model_config = ConfigDict(protected_namespaces=())
    query: str
    stream: bool = False
    model_name: Optional[str] = None

class ImageTextRequest(BaseModel):
    model_config = ConfigDict(protected_namespaces=())
    query: str
    stream: bool = False
    model_name: Optional[str] = None
    
    @classmethod
    def as_form(
        cls,
        query: str = Form(...),
        stream: bool = Form(False),
        model_name: Optional[str] = Form(None),
        image: UploadFile = File(...)  # Make image required for i2t2t
    ):
        return cls(
            query=query,
            stream=stream,
            model_name=model_name
        ), image

def get_client(model_name: Optional[str] = None):
    """Get inference client for specified model or default model"""
    try:
        model_path = model_name if model_name and model_name.strip() else DEFAULT_MODEL
        return InferenceClient(
            model=model_path
        )
    except Exception as e:
        raise HTTPException(
            status_code=400, 
            detail=f"Error initializing model {model_path}: {str(e)}"
        )

def generate_text_response(query: str, model_name: Optional[str] = None):
    messages = [{
        "role": "user",
        "content": f"[SYSTEM] You are ASSISTANT who answer question asked by user in short and concise manner. [USER] {query}"
    }]

    try:
        client = get_client(model_name)
        for message in client.chat_completion(
            messages,
            max_tokens=2048,
            stream=True
        ):
            token = message.choices[0].delta.content
            yield token
    except Exception as e:
        yield f"Error generating response: {str(e)}"

def generate_image_text_response(query: str, image_data: str, model_name: Optional[str] = None):
    messages = [
        {
            "role": "user",
            "content": [
                {"type": "text", "text": f"[SYSTEM] You are ASSISTANT who answer question asked by user in short and concise manner. [USER] {query}"},
                {"type": "image_url", "image_url": {"url": f"data:image/*;base64,{image_data}"}}
            ]
        }
    ]
    
    logger.debug(f"Messages sent to API: {messages}")
    
    try:
        client = get_client(model_name)
        for message in client.chat_completion(messages, max_tokens=2048, stream=True):
            logger.debug(f"Received message chunk: {message}")
            token = message.choices[0].delta.content
            yield token
    except Exception as e:
        logger.error(f"Error in generate_image_text_response: {str(e)}")
        yield f"Error generating response: {str(e)}"

def preprocess_image(img):
    """Enhance image for better OCR results"""
    # Convert to grayscale
    img = img.convert('L')
    
    # Enhance contrast
    enhancer = ImageEnhance.Contrast(img)
    img = enhancer.enhance(2.0)
    
    # Enhance sharpness
    enhancer = ImageEnhance.Sharpness(img)
    img = enhancer.enhance(1.5)
    
    return img

@app.get("/")
async def root():
    return {"message": "Welcome to FastAPI server!"}

@app.post("/t2t")
async def text_to_text(request: TextRequest):
    try:
        if request.stream:
            return StreamingResponse(
                generate_text_response(request.query, request.model_name),
                media_type="text/event-stream"
            )
        else:
            response = ""
            for chunk in generate_text_response(request.query, request.model_name):
                response += chunk
            return {"response": response}
    except Exception as e:
        logger.error(f"Error in /t2t endpoint: {str(e)}")
        raise HTTPException(status_code=500, detail=str(e))

@app.post("/i2t2t")
async def image_text_to_text(form_data: tuple[ImageTextRequest, UploadFile] = Depends(ImageTextRequest.as_form)):
    form, image = form_data
    try:
        # Process image
        contents = await image.read()
        try:
            logger.debug("Attempting to open image")
            img = Image.open(BytesIO(contents))
            if img.mode != 'RGB':
                img = img.convert('RGB')
            
            buffer = BytesIO()
            img.save(buffer, format="PNG")
            image_data = b64encode(buffer.getvalue()).decode('utf-8')
            logger.debug("Image processed and encoded to base64")
        except Exception as img_error:
            logger.error(f"Error processing image: {str(img_error)}")
            raise HTTPException(
                status_code=422,
                detail=f"Error processing image: {str(img_error)}"
            )
        
        if form.stream:
            return StreamingResponse(
                generate_image_text_response(form.query, image_data, form.model_name),
                media_type="text/event-stream"
            )
        else:
            response = ""
            for chunk in generate_image_text_response(form.query, image_data, form.model_name):
                response += chunk
            return {"response": response}
    except Exception as e:
        logger.error(f"Error in /i2t2t endpoint: {str(e)}")
        raise HTTPException(status_code=500, detail=str(e))

@app.post("/tes")
async def ocr_endpoint(image: UploadFile = File(...)):
    try:
        # Read and process the image
        contents = await image.read()
        img = Image.open(BytesIO(contents))
        
        # Preprocess the image
        img = preprocess_image(img)
        
        # Perform OCR with timeout and retries
        max_retries = 3
        text = ""
        
        for attempt in range(max_retries):
            try:
                text = pytesseract.image_to_string(
                    img,
                    timeout=30,  # 30 second timeout
                    config='--oem 3 --psm 6'
                )
                break
            except Exception as e:
                if attempt == max_retries - 1:
                    raise HTTPException(
                        status_code=500,
                        detail=f"Error extracting text: {str(e)}"
                    )
                time.sleep(1)  # Wait before retry
        
        return {"text": text}
        
    except Exception as e:
        raise HTTPException(
            status_code=500,
            detail=f"Error processing image: {str(e)}"
        )

@app.get("/docs/guide", response_class=HTMLResponse)
async def api_guide():
    html_content = '''
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <meta name="viewport" content="width=device-width, initial-scale=1.0">
        <title>API Documentation</title>
        <link href="https://cdn.jsdelivr.net/npm/[email protected]/dist/tailwind.min.css" rel="stylesheet">
        <link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/themes/prism-tomorrow.min.css">
        <style>
            .copy-button {
                position: absolute;
                top: 8px;
                right: 8px;
                padding: 4px 8px;
                background: #2d3748;
                border: 1px solid #4a5568;
                border-radius: 4px;
                color: #cbd5e0;
                font-size: 12px;
                cursor: pointer;
                transition: all 0.2s;
            }
            .copy-button:hover {
                background: #4a5568;
            }
            .code-block {
                position: relative;
                margin: 1rem 0;
            }
            .endpoint-card {
                background: #1a202c;
                border-radius: 8px;
                margin-bottom: 2rem;
                padding: 1.5rem;
            }
            .language-tab {
                cursor: pointer;
                padding: 0.5rem 1rem;
                border-radius: 4px 4px 0 0;
            }
            .language-tab.active {
                background: #2d3748;
                color: #fff;
            }
        </style>
    </head>
    <body class="bg-gray-900 text-gray-100 min-h-screen p-8">
        <div class="max-w-6xl mx-auto">
            <h1 class="text-4xl font-bold mb-8">API Documentation</h1>
            
            <!-- T2T Endpoint -->
            <div class="endpoint-card">
                <h2 class="text-2xl font-semibold mb-4">Text-to-Text Endpoint</h2>
                <p class="mb-4 text-gray-400">Endpoint for general text queries</p>
                <p class="mb-2 text-gray-300"><span class="font-mono bg-gray-800 px-2 py-1 rounded">POST /t2t</span></p>
                
                <div class="code-block">
                    <div class="flex mb-2">
                        <div class="language-tab active" data-lang="curl">cURL</div>
                        <div class="language-tab" data-lang="python">Python</div>
                        <div class="language-tab" data-lang="javascript">JavaScript</div>
                        <div class="language-tab" data-lang="node">Node.js</div>
                    </div>
                    <pre><code class="language-bash">curl -X POST "http://localhost:8000/t2t" \
-H "Content-Type: application/json" \
-d '{"query": "What is FastAPI?", "stream": false}'</code></pre>
                    <button class="copy-button">Copy</button>
                </div>
            </div>

            <!-- I2T2T Endpoint -->
            <div class="endpoint-card">
                <h2 class="text-2xl font-semibold mb-4">Image and Text to Text Endpoint</h2>
                <p class="mb-4 text-gray-400">Endpoint for queries about images</p>
                <p class="mb-2 text-gray-300"><span class="font-mono bg-gray-800 px-2 py-1 rounded">POST /i2t2t</span></p>
                
                <div class="code-block">
                    <div class="flex mb-2">
                        <div class="language-tab active" data-lang="curl">cURL</div>
                        <div class="language-tab" data-lang="python">Python</div>
                        <div class="language-tab" data-lang="javascript">JavaScript</div>
                        <div class="language-tab" data-lang="node">Node.js</div>
                    </div>
                    <pre><code class="language-bash">curl -X POST "http://localhost:8000/i2t2t" \
-F "query=Describe this image" \
-F "stream=false" \
-F "image=@/path/to/your/image.jpg"</code></pre>
                    <button class="copy-button">Copy</button>
                </div>
            </div>

            <!-- TES Endpoint -->
            <div class="endpoint-card">
                <h2 class="text-2xl font-semibold mb-4">OCR Endpoint</h2>
                <p class="mb-4 text-gray-400">Extract text from images using OCR</p>
                <p class="mb-2 text-gray-300"><span class="font-mono bg-gray-800 px-2 py-1 rounded">POST /tes</span></p>
                
                <div class="code-block">
                    <div class="flex mb-2">
                        <div class="language-tab active" data-lang="curl">cURL</div>
                        <div class="language-tab" data-lang="python">Python</div>
                        <div class="language-tab" data-lang="javascript">JavaScript</div>
                        <div class="language-tab" data-lang="node">Node.js</div>
                    </div>
                    <pre><code class="language-bash">curl -X POST "http://localhost:8000/tes" \
-F "image=@/path/to/your/image.jpg"</code></pre>
                    <button class="copy-button">Copy</button>
                </div>
            </div>
        </div>

        <script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/prism.min.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/components/prism-python.min.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/components/prism-javascript.min.js"></script>
        <script src="https://cdnjs.cloudflare.com/ajax/libs/prism/1.24.1/components/prism-bash.min.js"></script>
        <script>
            const codeExamples = {
                't2t': {
                    'curl': `curl -X POST "http://localhost:8000/t2t" \\
-H "Content-Type: application/json" \\
-d '{"query": "What is FastAPI?", "stream": false}'`,
                    'python': `import requests

url = "http://localhost:8000/t2t"
payload = {
    "query": "What is FastAPI?",
    "stream": False
}
response = requests.post(url, json=payload)
print(response.json())`,
                    'javascript': `// Using fetch
fetch("http://localhost:8000/t2t", {
    method: "POST",
    headers: {
        "Content-Type": "application/json",
    },
    body: JSON.stringify({
        query: "What is FastAPI?",
        stream: false
    })
})
.then(response => response.json())
.then(data => console.log(data));`,
                    'node': `const axios = require('axios');

async function makeRequest() {
    try {
        const response = await axios.post('http://localhost:8000/t2t', {
            query: "What is FastAPI?",
            stream: false
        });
        console.log(response.data);
    } catch (error) {
        console.error(error);
    }
}

makeRequest();`
                },
                'i2t2t': {
                    'curl': `curl -X POST "http://localhost:8000/i2t2t" \\
-F "query=Describe this image" \\
-F "stream=false" \\
-F "image=@/path/to/your/image.jpg"`,
                    'python': `import requests

url = "http://localhost:8000/i2t2t"
files = {
    'image': ('image.jpg', open('path/to/image.jpg', 'rb')),
}
data = {
    'query': 'Describe this image',
    'stream': 'false'
}
response = requests.post(url, files=files, data=data)
print(response.json())`,
                    'javascript': `const formData = new FormData();
formData.append('image', imageFile);
formData.append('query', 'Describe this image');
formData.append('stream', 'false');

fetch("http://localhost:8000/i2t2t", {
    method: "POST",
    body: formData
})
.then(response => response.json())
.then(data => console.log(data));`,
                    'node': `const axios = require('axios');
const FormData = require('form-data');
const fs = require('fs');

async function makeRequest() {
    try {
        const formData = new FormData();
        formData.append('image', fs.createReadStream('path/to/image.jpg'));
        formData.append('query', 'Describe this image');
        formData.append('stream', 'false');

        const response = await axios.post('http://localhost:8000/i2t2t', formData, {
            headers: formData.getHeaders()
        });
        console.log(response.data);
    } catch (error) {
        console.error(error);
    }
}

makeRequest();`
                },
                'tes': {
                    'curl': `curl -X POST "http://localhost:8000/tes" \\
-F "image=@/path/to/your/image.jpg"`,
                    'python': `import requests

url = "http://localhost:8000/tes"
files = {
    'image': ('image.jpg', open('path/to/image.jpg', 'rb'))
}
response = requests.post(url, files=files)
print(response.json())`,
                    'javascript': `const formData = new FormData();
formData.append('image', imageFile);

fetch("http://localhost:8000/tes", {
    method: "POST",
    body: formData
})
.then(response => response.json())
.then(data => console.log(data));`,
                    'node': `const axios = require('axios');
const FormData = require('form-data');
const fs = require('fs');

async function makeRequest() {
    try {
        const formData = new FormData();
        formData.append('image', fs.createReadStream('path/to/image.jpg'));

        const response = await axios.post('http://localhost:8000/tes', formData, {
            headers: formData.getHeaders()
        });
        console.log(response.data);
    } catch (error) {
        console.error(error);
    }
}

makeRequest();`
                }
            };

            // Handle language tab switching
            document.querySelectorAll('.language-tab').forEach(tab => {
                tab.addEventListener('click', () => {
                    const lang = tab.dataset.lang;
                    const codeBlock = tab.closest('.endpoint-card');
                    const endpoint = codeBlock.querySelector('h2').textContent.toLowerCase().includes('ocr') ? 'tes' : 
                                   codeBlock.querySelector('h2').textContent.toLowerCase().includes('image') ? 'i2t2t' : 't2t';
                    
                    // Update active tab
                    codeBlock.querySelectorAll('.language-tab').forEach(t => t.classList.remove('active'));
                    tab.classList.add('active');
                    
                    // Update code content
                    const code = codeBlock.querySelector('code');
                    code.textContent = codeExamples[endpoint][lang];
                    code.className = `language-${lang === 'curl' ? 'bash' : lang}`;
                    Prism.highlightElement(code);
                });
            });

            // Handle copy buttons
            document.querySelectorAll('.copy-button').forEach(button => {
                button.addEventListener('click', () => {
                    const code = button.previousElementSibling.textContent;
                    navigator.clipboard.writeText(code);
                    
                    // Show feedback
                    const originalText = button.textContent;
                    button.textContent = 'Copied!';
                    setTimeout(() => {
                        button.textContent = originalText;
                    }, 2000);
                });
            });
        </script>
    </body>
    </html>
    '''
    return HTMLResponse(content=html_content)