import os
import uuid
import asyncio
from fastapi import APIRouter, UploadFile, File, HTTPException, Query
from fastapi.responses import FileResponse
from pydantic import BaseModel
from typing import Optional
from app.config import settings

router = APIRouter()

class EditRequest(BaseModel):
    file_id: str
    cut_start_ms: Optional[float] = None
    cut_end_ms: Optional[float] = None
    zero_crossing_align: bool = True
    loop_count: int = 1
    fade_in_ms: float = 0.0
    fade_out_ms: float = 0.0
    volume_change_db: float = 0.0

class ExportRequest(BaseModel):
    file_id: str
    format: str = "wav"
    sample_rate: int = 44100
    bit_depth: int = 16

class AIAnalysisRequest(BaseModel):
    file_id: str
    api_base_url: Optional[str] = None
    model: str = "deepseek-chat"

@router.post("/upload")
async def upload_audio(file: UploadFile = File(...)):
    ext = os.path.splitext(file.filename)[1]
    if not ext:
        ext = ".wav"
    file_id = f"{uuid.uuid4()}{ext}"
    file_path = os.path.join(settings.UPLOADS_DIR, file_id)
    
    with open(file_path, "wb") as f:
        content = await file.read()
        f.write(content)
        
    # Trigger celery task
    from app.tasks.worker import analyze_audio_task
    task = analyze_audio_task.delay(file_id)
    
    return {
        "file_id": file_id,
        "filename": file.filename,
        "analysis_task_id": task.id
    }

@router.post("/edit")
async def edit_audio(req: EditRequest):
    upload_path = os.path.join(settings.UPLOADS_DIR, req.file_id)
    processed_path = os.path.join(settings.PROCESSED_DIR, req.file_id)
    
    # Use uploaded file if it exists, or look in processed if it was already edited
    if not os.path.exists(upload_path) and not os.path.exists(processed_path):
        raise HTTPException(status_code=404, detail="File not found")
        
    from app.tasks.worker import edit_audio_task
    task = edit_audio_task.delay(req.dict())
    
    return {
        "task_id": task.id
    }

@router.get("/download/{file_id}")
async def download_audio(file_id: str):
    processed_path = os.path.join(settings.PROCESSED_DIR, file_id)
    upload_path = os.path.join(settings.UPLOADS_DIR, file_id)
    
    if os.path.exists(processed_path):
        return FileResponse(processed_path, media_type="audio/wav", filename=file_id)
    elif os.path.exists(upload_path):
        return FileResponse(upload_path, media_type="audio/wav", filename=file_id)
    
    raise HTTPException(status_code=404, detail="File not found")

@router.get("/waveform/{file_id}")
async def get_waveform(file_id: str, num_peaks: int = Query(default=800, ge=50, le=4000)):
    """
    API endpoint vẽ Peak Waveform đồng bộ (Week 2).
    Trả về dữ liệu peak waveform cho hiển thị đồ thị sóng âm trên Frontend.
    """
    upload_path = os.path.join(settings.UPLOADS_DIR, file_id)
    processed_path = os.path.join(settings.PROCESSED_DIR, file_id)
    
    if os.path.exists(processed_path):
        file_path = processed_path
    elif os.path.exists(upload_path):
        file_path = upload_path
    else:
        raise HTTPException(status_code=404, detail="File not found")
    
    from app.core.dsp_utils import generate_peak_waveform
    return await asyncio.to_thread(generate_peak_waveform, file_path, num_peaks)

@router.get("/waveform-rms/{file_id}")
async def get_waveform_rms(file_id: str, num_points: int = Query(default=800, ge=50, le=4000)):
    """
    API endpoint vẽ RMS Waveform (mượt hơn peak).
    """
    upload_path = os.path.join(settings.UPLOADS_DIR, file_id)
    processed_path = os.path.join(settings.PROCESSED_DIR, file_id)
    
    if os.path.exists(processed_path):
        file_path = processed_path
    elif os.path.exists(upload_path):
        file_path = upload_path
    else:
        raise HTTPException(status_code=404, detail="File not found")
    
    from app.core.dsp_utils import generate_rms_waveform
    return await asyncio.to_thread(generate_rms_waveform, file_path, num_points)

@router.post("/analyze-ai")
async def analyze_audio_with_ai(req: AIAnalysisRequest):
    """
    API endpoint phân tích cấu trúc khuôn nhạc bằng AI (Week 4).
    Gọi OpenAI Compatible API (DeepSeek/Ollama) để phân đoạn bố cục.
    """
    upload_path = os.path.join(settings.UPLOADS_DIR, req.file_id)
    processed_path = os.path.join(settings.PROCESSED_DIR, req.file_id)
    
    if os.path.exists(processed_path):
        file_path = processed_path
    elif os.path.exists(upload_path):
        file_path = upload_path
    else:
        raise HTTPException(status_code=404, detail="File not found")
    
    from app.tasks.worker import analyze_ai_task
    task = analyze_ai_task.delay(
        file_id=req.file_id,
        api_base_url=req.api_base_url,
        model=req.model
    )
    
    return {
        "task_id": task.id,
        "file_id": req.file_id
    }

@router.post("/export")
async def export_audio(req: ExportRequest):
    """
    API endpoint xuất tệp âm thanh sang nhiều định dạng (WAV/MP3/OGG).
    """
    upload_path = os.path.join(settings.UPLOADS_DIR, req.file_id)
    processed_path = os.path.join(settings.PROCESSED_DIR, req.file_id)
    
    if os.path.exists(processed_path):
        source_path = processed_path
    elif os.path.exists(upload_path):
        source_path = upload_path
    else:
        raise HTTPException(status_code=404, detail="File not found")
    
    from app.tasks.worker import export_audio_task
    task = export_audio_task.delay(
        file_id=req.file_id,
        format=req.format,
        sample_rate=req.sample_rate,
        bit_depth=req.bit_depth
    )
    
    return {
        "task_id": task.id,
        "file_id": req.file_id
    }