#!/usr/bin/env bash
set -euo pipefail

# Force verbose download progress even in non-TTY environments
export HF_HUB_DISABLE_PROGRESS_BARS=0
export TRANSFORMERS_VERBOSITY=info
export HF_HUB_VERBOSITY=info
export WANDB_DISABLE_WEAVE="${WANDB_DISABLE_WEAVE:-true}"

echo "============================================"
echo "  F13 Qwen 3.5 Fine-Tuning Container"
echo "============================================"

if [ -n "${RUNPOD_POD_ID:-}" ]; then
    echo "Running on RunPod pod: ${RUNPOD_POD_ID}"
elif [ -n "${AWS_INSTANCE_ID:-}" ]; then
    echo "Running on AWS instance: ${AWS_INSTANCE_ID}"
fi

NUM_NODES="${NUM_NODES:-1}"
NODE_RANK="${NODE_RANK:-0}"
if [ "${NUM_NODES}" -gt 1 ]; then
    echo ""
    echo "--- Multi-Node Cluster ---"
    echo "  Nodes:       ${NUM_NODES}"
    echo "  This rank:   ${NODE_RANK}"
    echo "  Master:      ${MASTER_ADDR:-unknown}:${MASTER_PORT:-29500}"
    echo "  Node addr:   ${NODE_ADDR:-unknown}"
    echo "  World size:  ${WORLD_SIZE:-unknown}"
    echo "  GPUs/node:   ${NUM_TRAINERS:-unknown}"

    if [ -n "${PRIMARY_ADDR:-}" ]; then
        export NCCL_SOCKET_IFNAME="${NCCL_SOCKET_IFNAME:-ens1}"
        echo "  NCCL iface:  ${NCCL_SOCKET_IFNAME}"
    fi
    echo "--------------------------"
    echo ""
    echo "--- Network Interfaces ---"
    ip -4 addr show 2>/dev/null || echo "(ip command not available)"
    echo ""
    echo "--- Connectivity Test ---"
    if [ -n "${MASTER_ADDR:-}" ]; then
        echo -n "  TCP to ${MASTER_ADDR}:${MASTER_PORT:-29500} -> "
        timeout 3 bash -c "echo > /dev/tcp/${MASTER_ADDR}/${MASTER_PORT:-29500}" 2>/dev/null && echo "OK" || echo "UNREACHABLE (expected before torchrun)"
        echo -n "  TCP to ${MASTER_ADDR}:8080 -> "
        timeout 3 bash -c "echo > /dev/tcp/${MASTER_ADDR}/8080" 2>/dev/null && echo "OK" || echo "UNREACHABLE (master API may not be up yet)"
    fi
    echo "--------------------------"
fi

nvidia-smi || echo "Warning: nvidia-smi not available"
echo ""

# --- SSH Setup ---
SSH_PORT="${SSH_PORT:-22}"
mkdir -p /var/run/sshd /root/.ssh
chmod 700 /root/.ssh

if [ -n "${PUBLIC_KEY:-}" ]; then
    echo "${PUBLIC_KEY}" > /root/.ssh/authorized_keys
    chmod 600 /root/.ssh/authorized_keys
    echo "SSH public key installed."
fi

if [ -n "${SSH_PASSWORD:-}" ]; then
    echo "root:${SSH_PASSWORD}" | chpasswd
    sed -i 's/#*PermitRootLogin.*/PermitRootLogin yes/' /etc/ssh/sshd_config
    sed -i 's/#*PasswordAuthentication.*/PasswordAuthentication yes/' /etc/ssh/sshd_config
    echo "SSH password auth enabled."
else
    sed -i 's/#*PasswordAuthentication.*/PasswordAuthentication no/' /etc/ssh/sshd_config
fi

sed -i "s/#*Port .*/Port ${SSH_PORT}/" /etc/ssh/sshd_config

if [ ! -f /etc/ssh/ssh_host_rsa_key ]; then
    ssh-keygen -A
fi

/usr/sbin/sshd
echo "SSH daemon started on port ${SSH_PORT}"

# --- HuggingFace / W&B ---
if [ -n "${HF_TOKEN:-}" ]; then
    echo "HF_TOKEN is set — logging into HuggingFace Hub..."
    hf auth login --token "${HF_TOKEN}" --add-to-git-credential 2>/dev/null || true
    echo "HuggingFace login complete."
else
    echo "HF_TOKEN not set — only public models/datasets available."
fi

if [ -n "${WANDB_API_KEY:-}" ]; then
    echo "WANDB_API_KEY is set — W&B logging available."
    wandb login "${WANDB_API_KEY}" 2>/dev/null || true
else
    echo "WANDB_API_KEY not set — W&B logging disabled by default."
fi
echo ""

# --- Default dataset ---
if [ ! -f "/workspace/data/train.jsonl" ]; then
    echo "No custom train.jsonl found, copying bundled default dataset."
    mkdir -p /workspace/data
    cp /opt/f13/data/train.jsonl /workspace/data/train.jsonl
    cp /opt/f13/data/test.jsonl /workspace/data/test.jsonl
else
    echo "Found custom dataset at /workspace/data/train.jsonl"
fi

# --- Pre-flight: verify key CUDA packages ---
echo "Verifying GPU-accelerated packages..."
python3 -c "
checks = []
try:
    import flash_attn; checks.append(f'flash-attn {flash_attn.__version__}')
except Exception as e: checks.append(f'flash-attn MISSING: {e}')
try:
    import fla; checks.append('flash-linear-attention OK')
    from fla.ops.gated_delta_rule import fused_recurrent_gated_delta_rule
    checks.append('  GatedDeltaNet FLA kernel OK')
except Exception as e: checks.append(f'flash-linear-attention MISSING: {e}')
try:
    import causal_conv1d; checks.append('causal-conv1d OK')
except Exception as e: checks.append(f'causal-conv1d MISSING: {e}')
for c in checks: print(f'  [{\"OK\" if \"MISSING\" not in c else \"WARN\"}] {c}')
"
echo ""

# --- API Server ---
API_PORT="${API_PORT:-8080}"
echo ""
echo "Starting API server on port ${API_PORT}..."

if [ -z "${API_SECRET:-}" ]; then
    echo "WARNING: API_SECRET is not set. All API calls will be rejected."
    echo "         Set API_SECRET env var to enable the training API."
fi

if [ "${AUTO_TRAIN:-false}" = "true" ]; then
    echo "AUTO_TRAIN=true — training will start after API server is up."
fi

exec uvicorn server.app:app \
    --host 0.0.0.0 \
    --port "${API_PORT}" \
    --app-dir /opt/f13