package com.narutohuo.xindazhou.ble.util

import android.bluetooth.BluetoothAdapter
import android.bluetooth.BluetoothDevice
import android.bluetooth.BluetoothManager
import android.bluetooth.le.BluetoothLeScanner
import android.bluetooth.le.ScanCallback
import android.bluetooth.le.ScanFilter
import android.bluetooth.le.ScanResult
import android.bluetooth.le.ScanSettings
import android.content.Context
import android.os.Handler
import android.os.Looper
import com.narutohuo.xindazhou.core.log.ILog

/**
 * BLE扫描器
 * 
 * 负责 BLE 设备的扫描，返回符合过滤条件的 BluetoothDevice 列表
 * 使用 Android 12+ 推荐的 BluetoothLeScanner API
 */
class BleScanner(
    private val context: Context,
    private val onDeviceFound: (BluetoothDevice) -> Unit,
    private val onScanFinished: () -> Unit
) {
    
    private val tag = "BleScanner"
    
    private val bluetoothAdapter: BluetoothAdapter by lazy {
        val manager = context.getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
        manager.adapter
    }
    
    private var scanner: BluetoothLeScanner? = null
    private var scanning = false
    
    private val scanCallback = object : ScanCallback() {
        override fun onScanResult(callbackType: Int, result: ScanResult) {
            result.device?.let {
                onDeviceFound(it)
                stopScan()
            }
        }
        
        override fun onBatchScanResults(results: List<ScanResult>) {
            results.forEach {
                it.device?.let { device ->
                    onDeviceFound(device)
                    stopScan()
                }
            }
        }
        
        override fun onScanFailed(errorCode: Int) {
            ILog.e(tag, "BLE scan failed, error=$errorCode")
            stopScan()
        }
    }
    
    /**
     * 开始扫描（默认 10 秒后自动停止）
     */
    @android.annotation.SuppressLint("MissingPermission")
    fun startScan(filterNamePrefix: String? = null, timeoutMs: Long = 10_000L) {
        if (scanning) return
        
        scanner = bluetoothAdapter.bluetoothLeScanner
        val settings = ScanSettings.Builder()
            .setScanMode(ScanSettings.SCAN_MODE_LOW_LATENCY)
            .build()
        
        val filters = mutableListOf<ScanFilter>()
        filterNamePrefix?.let {
            filters.add(ScanFilter.Builder().setDeviceName(it).build())
        }
        
        try {
            scanner?.startScan(filters, settings, scanCallback)
            scanning = true
            ILog.d(tag, "开始扫描BLE设备，过滤前缀: $filterNamePrefix")
            
            // 超时自动停止
            Handler(Looper.getMainLooper()).postDelayed({ stopScan() }, timeoutMs)
        } catch (e: SecurityException) {
            ILog.e(tag, "扫描权限不足", e)
            scanning = false
        } catch (e: Exception) {
            ILog.e(tag, "启动扫描失败", e)
            scanning = false
        }
    }
    
    /**
     * 停止扫描
     */
    @android.annotation.SuppressLint("MissingPermission")
    fun stopScan() {
        if (!scanning) return
        
        try {
            scanner?.stopScan(scanCallback)
            scanning = false
            ILog.d(tag, "停止扫描")
            onScanFinished()
        } catch (e: SecurityException) {
            ILog.e(tag, "停止扫描权限不足", e)
        } catch (e: Exception) {
            ILog.e(tag, "停止扫描失败", e)
        }
    }
}