main.py

from fastapi import FastAPI, HTTPException
from fastapi.responses import JSONResponse
from fastapi.exceptions import ResponseValidationError
from starlette.requests import Request
from fastapi.staticfiles import StaticFiles
from pydantic import BaseModel
from models.schemas import (
    SEORequest, SEOResponse,
    YouTubeResponse, InstagramResponse, LinkedInResponse,
    FacebookResponse, TwitterResponse, TikTokResponse, PinterestResponse,
    GrammarRequest, GrammarResponse, BatchRequest
)
from services.batch_analyzer import analyze_batch
from services.analyzer import analyze_seo_content
from services.youtube_analyzer import analyze_youtube
from services.instagram_analyzer import analyze_instagram
from services.linkedin_analyzer import analyze_linkedin
from services.linkedin_api import get_oauth_url, exchange_code, get_user_info, create_post
from services.facebook_analyzer import analyze_facebook
from services.twitter_analyzer import analyze_twitter
from services.tiktok_analyzer import analyze_tiktok
from services.pinterest_analyzer import analyze_pinterest
from services.grammar_analyzer import analyze_grammar
import uvicorn
import traceback

app = FastAPI(
    title="Social Media SEO & Grammar API",
    description="Professional social media content analysis + grammar correction using Generative AI. Covers YouTube, Instagram, LinkedIn, Facebook, X/Twitter, TikTok, Pinterest, and grammar correction.",
    version="2.1.0"
)

ERROR_MASK = "An internal error occurred. Please try again later."
ERROR_MASK_VALIDATION = "The model returned an incomplete response. Please try again."


@app.exception_handler(ResponseValidationError)
async def validation_exception_handler(request: Request, exc: ResponseValidationError):
    print(f"[ValidationError] {exc}")
    return JSONResponse(
        status_code=200,
        content={"error": ERROR_MASK_VALIDATION},
    )


def safe_analyze(analyze_fn, content: str):
    try:
        result = analyze_fn(content)
        if isinstance(result, dict) and result.get("error"):
            print(f"[Warning] Analysis completed with error: {result['error']}")
        return result
    except HTTPException:
        raise
    except Exception as e:
        print(f"CRITICAL SERVER ERROR: {e}\n{traceback.format_exc()}")
        raise HTTPException(status_code=500, detail=ERROR_MASK)

# ---------------------------------------------------------------------------
# Root - Serve static frontend
# ---------------------------------------------------------------------------

app.mount("/static", StaticFiles(directory="static"), name="static")


@app.get("/")
async def read_root():
    from fastapi.responses import FileResponse
    return FileResponse("static/index.html")

# ---------------------------------------------------------------------------
# Generic SEO
# ---------------------------------------------------------------------------

@app.post("/analyze-seo", response_model=SEOResponse)
def analyze_seo(request: SEORequest):
    return safe_analyze(analyze_seo_content, request.content)

# ---------------------------------------------------------------------------
# YouTube
# ---------------------------------------------------------------------------

@app.post("/analyze/youtube", response_model=YouTubeResponse)
def analyze_youtube_route(request: SEORequest):
    return safe_analyze(analyze_youtube, request.content)

# ---------------------------------------------------------------------------
# Instagram
# ---------------------------------------------------------------------------

@app.post("/analyze/instagram", response_model=InstagramResponse)
def analyze_instagram_route(request: SEORequest):
    return safe_analyze(analyze_instagram, request.content)

# ---------------------------------------------------------------------------
# LinkedIn
# ---------------------------------------------------------------------------

@app.post("/analyze/linkedin", response_model=LinkedInResponse)
def analyze_linkedin_route(request: SEORequest):
    return safe_analyze(analyze_linkedin, request.content)


@app.get("/api/linkedin/auth-url")
def linkedin_auth_url(state: str = ""):
    url = get_oauth_url(state)
    return {"url": url}


class TokenExchangeRequest(BaseModel):
    code: str


@app.post("/api/linkedin/exchange-token")
def linkedin_exchange_token(req: TokenExchangeRequest):
    token_data, err = exchange_code(req.code)
    if err:
        raise HTTPException(status_code=400, detail=err)
    user_info, uerr = get_user_info(token_data["access_token"])
    if uerr:
        raise HTTPException(status_code=400, detail=uerr)
    return {
        "access_token": token_data["access_token"],
        "expires_at": token_data["expires_at"],
        "user": user_info,
    }


class PostToLinkedInRequest(BaseModel):
    access_token: str
    author_urn: str
    text: str
    hashtags: list[str] = []


@app.post("/api/linkedin/post")
def linkedin_post(req: PostToLinkedInRequest):
    result, err = create_post(req.access_token, req.author_urn, req.text, req.hashtags)
    if err:
        raise HTTPException(status_code=400, detail=err)
    return {"success": True, **result}


# ---------------------------------------------------------------------------
# Facebook
# ---------------------------------------------------------------------------

@app.post("/analyze/facebook", response_model=FacebookResponse)
def analyze_facebook_route(request: SEORequest):
    return safe_analyze(analyze_facebook, request.content)

# ---------------------------------------------------------------------------
# X / Twitter
# ---------------------------------------------------------------------------

@app.post("/analyze/twitter", response_model=TwitterResponse)
def analyze_twitter_route(request: SEORequest):
    return safe_analyze(analyze_twitter, request.content)

# ---------------------------------------------------------------------------
# TikTok
# ---------------------------------------------------------------------------

@app.post("/analyze/tiktok", response_model=TikTokResponse)
def analyze_tiktok_route(request: SEORequest):
    return safe_analyze(analyze_tiktok, request.content)

# ---------------------------------------------------------------------------
# Pinterest
# ---------------------------------------------------------------------------

@app.post("/analyze/pinterest", response_model=PinterestResponse)
def analyze_pinterest_route(request: SEORequest):
    return safe_analyze(analyze_pinterest, request.content)

# ---------------------------------------------------------------------------
# Grammar Correction
# ---------------------------------------------------------------------------

@app.post("/analyze/grammar", response_model=GrammarResponse)
def grammar_correction_route(request: GrammarRequest):
    return safe_analyze(analyze_grammar, request.text)


# ---------------------------------------------------------------------------
# Batch - Multi-Platform
# ---------------------------------------------------------------------------

class BatchResponse(BaseModel):
    results: dict


@app.post("/analyze/batch", response_model=BatchResponse)
def batch_analyze_route(request: BatchRequest):
    results = safe_analyze(lambda c: analyze_batch(c, request.platforms), request.content)
    return {"results": results}


# ---------------------------------------------------------------------------
# Entrypoint
# ---------------------------------------------------------------------------

if __name__ == "__main__":
    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)