import os
import shutil
import subprocess
import uuid
from datetime import timedelta
from typing import List
from fastapi import FastAPI, UploadFile, File
from fastapi.responses import FileResponse, JSONResponse
from fastapi.middleware.cors import CORSMiddleware
from faster_whisper import WhisperModel
from pydantic import BaseModel

app = FastAPI(title="AI Subtitle Studio Pro")

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],
    allow_methods=["*"],
    allow_headers=["*"],
)

TEMP_DIR = "temp"
os.makedirs(TEMP_DIR, exist_ok=True)

print("⚡ [SYSTEM] Initializing AI Neural Network...")
model = WhisperModel("small", device="cpu", compute_type="int8")
print("✅ [SYSTEM] AI Core Ready.")

# --- MODELS ---
class SubtitleSegment(BaseModel):
    id: int
    start: float
    end: float
    text: str

class StyleConfig(BaseModel):
    font: str
    fontSize: int
    primaryColor: str
    outlineColor: str
    backType: str  
    outlineWidth: float
    marginV: int
    alignment: int 

class ProcessRequest(BaseModel):
    file_id: str
    segments: List[SubtitleSegment]
    style: StyleConfig

# --- HELPERS ---
def hex_to_ass(hex_color, alpha="00"):
    hex_color = hex_color.lstrip('#')
    if len(hex_color) != 6: return "&H00FFFFFF"
    r, g, b = hex_color[0:2], hex_color[2:4], hex_color[4:6]
    return f"&H{alpha}{b}{g}{r}"

def format_time_ass(seconds: float):
    td = timedelta(seconds=seconds)
    total_seconds = int(td.total_seconds())
    hours = total_seconds // 3600
    minutes = (total_seconds % 3600) // 60
    secs = total_seconds % 60
    centisecs = int(td.microseconds / 10000)
    return f"{hours:01d}:{minutes:02d}:{secs:02d}.{centisecs:02d}"

def generate_ass_file(data: ProcessRequest, output_path: str):
    s = data.style
    
    font_map = {
        "vazir": "Vazirmatn",
        "lalezar": "Lalezar",
        "roboto": "Roboto",
        "bangers": "Bangers"
    }
    font_name = font_map.get(s.font, "Arial")
    
    primary = hex_to_ass(s.primaryColor)
    outline = hex_to_ass(s.outlineColor)
    
    border_style = 1
    back_color = "&H00000000"
    
    if s.backType == 'solid':
        border_style = 3 
        outline = hex_to_ass(s.outlineColor, "00") 
    elif s.backType == 'transparent':
        border_style = 3
        outline = "&H80000000" 
    else:
        border_style = 1
        
    header = f"""[Script Info]
ScriptType: v4.00+
PlayResX: 1080
PlayResY: 1920
WrapStyle: 1
ScaledBorderAndShadow: yes

[V4+ Styles]
Format: Name, Fontname, Fontsize, PrimaryColour, SecondaryColour, OutlineColour, BackColour, Bold, Italic, Underline, StrikeOut, ScaleX, ScaleY, Spacing, Angle, BorderStyle, Outline, Shadow, Alignment, MarginL, MarginR, MarginV, Encoding
Style: Default,{font_name},{s.fontSize},{primary},&H000000FF,{outline},{back_color},1,0,0,0,100,100,0,0,{border_style},{s.outlineWidth},0,{s.alignment},10,10,{s.marginV},1

[Events]
Format: Layer, Start, End, Style, Name, MarginL, MarginR, MarginV, Effect, Text
"""
    with open(output_path, "w", encoding="utf-8") as f:
        f.write(header)
        for seg in data.segments:
            start = format_time_ass(seg.start)
            end = format_time_ass(seg.end)
            clean_text = seg.text.strip().replace("\n", "\\N")
            f.write(f"Dialogue: 0,{start},{end},Default,,0,0,0,,{clean_text}\n")

# --- ROUTES ---

@app.get("/")
async def home():
    return FileResponse("index.html")

@app.post("/api/analyze")
async def analyze_media(file: UploadFile = File(...)):
    try:
        file_id = str(uuid.uuid4())[:12]
        file_ext = file.filename.split('.')[-1]
        input_path = f"{TEMP_DIR}/{file_id}.{file_ext}"
        
        with open(input_path, "wb") as f:
            shutil.copyfileobj(file.file, f)
            
        segments_gen, _ = model.transcribe(input_path, language="fa", beam_size=5)
        
        results = []
        for idx, seg in enumerate(segments_gen):
            results.append({
                "id": idx,
                "start": seg.start,
                "end": seg.end,
                "text": seg.text.strip()
            })
            
        return {"status": "success", "file_id": file_id, "segments": results}
        
    except Exception as e:
        return JSONResponse(status_code=500, content={"error": str(e)})

@app.post("/api/render")
async def render_video(data: ProcessRequest):
    try:
        exts = ["mp4", "mov", "avi", "mkv", "mp3"]
        input_path = None
        for ext in exts:
            test_path = f"{TEMP_DIR}/{data.file_id}.{ext}"
            if os.path.exists(test_path):
                input_path = test_path
                break
        
        if not input_path:
            return JSONResponse(status_code=404, content={"error": "Source file lost"})
            
        ass_path = f"{TEMP_DIR}/{data.file_id}.ass"
        output_path = f"{TEMP_DIR}/{data.file_id}_final.mp4"
        
        generate_ass_file(data, ass_path)
        
        cmd = [
            "ffmpeg", "-y",
            "-i", input_path,
            "-vf", f"ass={ass_path}",
            "-c:v", "libx264", "-preset", "ultrafast", "-crf", "26",
            "-c:a", "aac",
            output_path
        ]
        subprocess.run(cmd, check=True, stdout=subprocess.DEVNULL, stderr=subprocess.DEVNULL)
        
        return {"status": "done", "url": f"/download/{data.file_id}_final.mp4"}
        
    except Exception as e:
        return JSONResponse(status_code=500, content={"error": str(e)})

@app.get("/download/{filename}")
async def get_file(filename: str):
    path = f"{TEMP_DIR}/{filename}"
    if os.path.exists(path):
        return FileResponse(path)
    return JSONResponse(status_code=404, content={"error": "File missing"})