#!/bin/bash
# 从epoch_19开始训练Enhanced版本
# 使用4个GPU以避免分布式同步死锁问题

set -e

export PATH=/opt/conda/bin:$PATH
cd /workspace/bevfusion

echo "=========================================="
echo "BEVFusion Enhanced训练 - 从Epoch 19继续"
echo "任务: 3D检测 + BEV分割（Enhanced Head）"
echo "=========================================="
echo ""
echo "配置信息："
echo "  GPU数量: 4x Tesla V100S (减少以避免死锁)"
echo "  基础模型: epoch_19.pth"
echo "  分割头: EnhancedBEVSegmentationHead"
echo "  特性: ASPP + 注意力 + Deep Supervision"
echo ""
echo "优化措施："
echo "  - 使用4个GPU而非8个（降低同步复杂度）"
echo "  - workers_per_gpu=0（避免共享内存问题）"
echo "  - 较小学习率（微调）"
echo ""
echo "预计训练时间: 6-8小时完成剩余1个epoch"
echo "预期性能提升:"
echo "  - 分割mIoU: 36% → 48-52%"
echo "  - 检测mAP: 保持65-68%"
echo ""
echo "=========================================="
echo ""

# 生成日志文件名
LOG_FILE="training_enhanced_from_epoch19_$(date +%Y%m%d_%H%M%S).log"

echo "训练日志将保存到: $LOG_FILE"
echo ""
echo "开始训练..."
echo ""

# 启动训练
torchpack dist-run -np 4 python tools/train.py \
  configs/nuscenes/det/transfusion/secfpn/camera+lidar/swint_v0p075/multitask.yaml \
  --model.encoders.camera.backbone.init_cfg.checkpoint pretrained/swint-nuimages-pretrained.pth \
  --load_from runs/run-326653dc-74184412/epoch_19.pth \
  --model.heads.map.type EnhancedBEVSegmentationHead \
  --model.heads.map.in_channels 512 \
  --model.heads.map.hidden_channels 256 \
  --model.heads.map.num_classes 6 \
  --model.heads.map.use_aspp true \
  --model.heads.map.use_channel_attention true \
  --model.heads.map.use_spatial_attention true \
  --model.heads.map.deep_supervision true \
  --model.heads.map.focal_alpha 0.25 \
  --model.heads.map.focal_gamma 2.0 \
  --model.heads.map.use_dice_loss true \
  --model.heads.map.dice_weight 0.5 \
  --model.heads.map.class_weights '[1.0, 3.0, 1.5, 4.0, 2.0, 3.0]' \
  --model.loss_scale.map 5.0 \
  --optimizer.lr 1.0e-4 \
  --data.workers_per_gpu 0 \
  --data.samples_per_gpu 2 \
  2>&1 | tee "$LOG_FILE"

echo ""
echo "=========================================="
echo "训练完成！"
echo "日志文件: $LOG_FILE"
echo "=========================================="