from fastapi import APIRouter, Depends, HTTPException, status
from sqlalchemy.orm import Session
from typing import List
from .. import models, schemas, auth
from ..database import get_db
from ..db_manager import DbManager
from ..scheduler import sync_scheduler_config
from fastapi.responses import FileResponse
from fastapi import UploadFile, File

router = APIRouter(
    prefix="/admin/db",
    tags=["Admin Database"]
)

@router.get("/backups", response_model=List[schemas.BackupInfo])
def get_backups(
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """List available database backups."""
    return DbManager.get_backup_list()

@router.get("/stats", response_model=schemas.DatabaseStats)
def get_db_stats(
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Get database backup storage statistics."""
    return DbManager.get_stats()

@router.post("/backup", response_model=schemas.BackupInfo)
def trigger_manual_backup(
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Trigger a manual database backup."""
    filename = DbManager.create_backup(db, label="manual", user_id=current_admin.sub)
    # Re-fetch the newly created file info
    backups = DbManager.get_backup_list()
    for b in backups:
        if b.filename == filename:
            return b
    raise HTTPException(status_code=500, detail="Backup created but info not found")

@router.post("/restore")
def restore_database(
    payload: dict,
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Restore database from a specific file. DANGEROUS."""
    filename = payload.get("filename")
    confirm = payload.get("confirm", False)
    
    if not filename:
        raise HTTPException(status_code=400, detail="Filename required")
    if not confirm:
        raise HTTPException(status_code=400, detail="Confirmation required")
        
    try:
        success = DbManager.restore_backup(filename, db, user_id=current_admin.sub)
        return {"status": "success", "message": f"Database restored from {filename}"}
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@router.get("/settings", response_model=schemas.DbSettingsUpdate)
def get_db_settings(
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Get database retention and scheduling settings."""
    # Ensure default settings exist
    retention = db.query(models.SystemSetting).filter(models.SystemSetting.key == "backup_retention_count").first()
    hour = db.query(models.SystemSetting).filter(models.SystemSetting.key == "backup_schedule_hour").first()
    freq = db.query(models.SystemSetting).filter(models.SystemSetting.key == "backup_schedule_freq_days").first()
    
    return {
        "retention_count": int(retention.value) if retention else 10,
        "schedule_hour": int(hour.value) if hour else 3,
        "schedule_freq_days": int(freq.value) if freq else 1
    }

@router.patch("/settings", response_model=schemas.DbSettingsUpdate)
def update_db_settings(
    settings: schemas.DbSettingsUpdate,
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Update database settings and re-trigger scheduler sync."""
    pairs = {
        "backup_retention_count": str(settings.retention_count),
        "backup_schedule_hour": str(settings.schedule_hour),
        "backup_schedule_freq_days": str(settings.schedule_freq_days)
    }
    
    for key, val in pairs.items():
        existing = db.query(models.SystemSetting).filter(models.SystemSetting.key == key).first()
        if existing:
            existing.value = val
        else:
            db.add(models.SystemSetting(key=key, value=val))
    
    db.commit()
    # Re-trigger scheduler sync
    sync_scheduler_config()
    return settings

@router.get("/export")
def export_database(
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Download the current database file."""
    try:
        path = DbManager.export_db()
        return FileResponse(
            path, 
            media_type="application/x-sqlite3", 
            filename="inventory_export.db"
        )
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

@router.post("/import")
async def import_database(
    file: UploadFile = File(...),
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Upload and replace the current database. DANGEROUS."""
    contents = await file.read()
    try:
        DbManager.import_db(contents, db, user_id=current_admin.sub)
        return {"status": "success", "message": "Database successfully imported and replaced."}
    except Exception as e:
        raise HTTPException(status_code=500, detail=str(e))

import os
from ..database import BASE_DIR
PROJECT_ROOT = os.path.dirname(BASE_DIR)
PROMPT_FILE_PATH = os.path.join(PROJECT_ROOT, "config", "ai_prompt.md")

@router.get("/settings/prompt")
def get_ai_prompt(
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Get the current AI extraction prompt (prioritizes config file)."""
    # 1. Try file first
    if os.path.exists(PROMPT_FILE_PATH):
        try:
            with open(PROMPT_FILE_PATH, 'r', encoding='utf-8') as f:
                return {"value": f.read().strip(), "source": "file"}
        except Exception as e:
            print(f"Error reading prompt file: {e}")

    # 2. Fallback to DB
    setting = db.query(models.SystemSetting).filter(models.SystemSetting.key == "ai_extraction_prompt").first()
    if not setting:
        return {"value": "", "source": "none"}
    return {"value": setting.value, "source": "database"}

@router.post("/settings/prompt")
def update_ai_prompt(
    payload: dict,
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Update the AI extraction prompt (writes to both file and DB)."""
    value = payload.get("value")
    if value is None:
        raise HTTPException(status_code=400, detail="Value required")
    
    # 1. Update File (Primary)
    try:
        os.makedirs(os.path.dirname(PROMPT_FILE_PATH), exist_ok=True)
        with open(PROMPT_FILE_PATH, 'w', encoding='utf-8') as f:
            f.write(value)
    except Exception as e:
        print(f"Failed to write prompt file: {e}")
        # We continue to DB update anyway

    # 2. Update DB (Backup/Sync)
    existing = db.query(models.SystemSetting).filter(models.SystemSetting.key == "ai_extraction_prompt").first()
    if existing:
        existing.value = value
    else:
        db.add(models.SystemSetting(key="ai_extraction_prompt", value=value))
    
    db.commit()
    return {"status": "success", "file_updated": os.path.exists(PROMPT_FILE_PATH)}

from ..config_manager import ConfigManager

@router.get("/settings/ai")
def get_ai_config(
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Check AI provider status and active provider."""
    gemini_key = os.environ.get("GEMINI_API_KEY")
    claude_key = os.environ.get("CLAUDE_API_KEY")
    
    # Get active provider from DB
    provider_setting = db.query(models.SystemSetting).filter(models.SystemSetting.key == "ai_provider").first()
    active_provider = provider_setting.value if provider_setting else "gemini"
    
    return {
        "active_provider": active_provider,
        "providers": [
            {
                "id": "gemini",
                "name": "Google Gemini 2.0",
                "configured": bool(gemini_key),
                "active": active_provider == "gemini",
                "masked_key": ConfigManager.get_masked_key("GEMINI_API_KEY")
            },
            {
                "id": "claude",
                "name": "Anthropic Claude 3.5",
                "configured": bool(claude_key),
                "active": active_provider == "claude",
                "masked_key": ConfigManager.get_masked_key("CLAUDE_API_KEY")
            }
        ]
    }

@router.post("/settings/ai-keys")
def update_ai_keys(
    payload: dict,
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Update AI API keys in inventory.env."""
    gemini_key = payload.get("gemini_api_key")
    claude_key = payload.get("claude_api_key")
    
    updates = {}
    if gemini_key:
        updates["GEMINI_API_KEY"] = gemini_key
    if claude_key:
        updates["CLAUDE_API_KEY"] = claude_key
        
    if not updates:
        return {"status": "no_change"}
        
    ConfigManager.update_keys(updates)
    return {
        "status": "success", 
        "gemini_configured": bool(os.environ.get("GEMINI_API_KEY")),
        "claude_configured": bool(os.environ.get("CLAUDE_API_KEY"))
    }

@router.post("/settings/test-ai-key")
def test_ai_key(
    payload: dict,
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Test AI API key connectivity."""
    provider = payload.get("provider")
    key = payload.get("key")
    
    if not provider or provider not in ["gemini", "claude"]:
        raise HTTPException(status_code=400, detail="Invalid provider")
    
    # If key is masked or empty, use the one from environment
    if not key or "****" in key:
        key = os.environ.get("GEMINI_API_KEY" if provider == "gemini" else "CLAUDE_API_KEY")
        
    if not key:
        raise HTTPException(status_code=400, detail="No API key provided or configured")

    try:
        if provider == "gemini":
            from google import genai
            client = genai.Client(api_key=key, http_options={'api_version': 'v1beta'})
            # Listing models is the standard way to check key validity
            client.models.list()
            return {"status": "success", "message": "Google Gemini API connection verified!"}
        
        elif provider == "claude":
            import anthropic
            client = anthropic.Anthropic(api_key=key)
            # Claude also supports model listing for key verification
            client.models.list(limit=1)
            return {"status": "success", "message": "Anthropic Claude API connection verified!"}
            
    except Exception as e:
        error_msg = str(e)
        if "API_KEY_INVALID" in error_msg or "invalid_api_key" in error_msg:
             error_msg = "The API key provided is invalid."
        elif "PERMISSION_DENIED" in error_msg:
             error_msg = "Permission denied. Check if the key has correct permissions."
             
        raise HTTPException(status_code=400, detail=f"{provider.capitalize()} Test Failed: {error_msg}")

@router.post("/settings/ai")
def update_ai_provider(
    payload: dict,
    db: Session = Depends(get_db),
    current_admin: auth.TokenData = Depends(auth.get_current_admin)
):
    """Update the active AI provider."""
    provider = payload.get("provider")
    if provider not in ["gemini", "claude"]:
        raise HTTPException(status_code=400, detail="Invalid provider. Must be 'gemini' or 'claude'.")
    
    existing = db.query(models.SystemSetting).filter(models.SystemSetting.key == "ai_provider").first()
    if existing:
        existing.value = provider
    else:
        db.add(models.SystemSetting(key="ai_provider", value=provider))
    
    db.commit()
    return {"status": "success", "active_provider": provider}