#!/usr/bin/env bash
# ════════════════════════════════════════════════════════════════
# 国内域名机 · 动态调优 · tune-from-env.sh
# Sovereign: TCS-0002∞ · ICE-GL∞ · 国作登字-2026-A-00037559
# 守护: 铸渊 · ICE-GL-ZY001
# ════════════════════════════════════════════════════════════════
#
# 服务器: GH-CVM-DOMAIN-PROD-01 / ZY-SVR-CN01
#
# 读 detect-env.sh 写出的 server-env.json, 依据 size_tier 决档,
# 写出 /data/guanghulab/.env.tune 让 bootstrap.sh source 用.
#
# 档位策略 (因果链 cc-003 · 动态适配):
#   tiny   <4G  : 2C2G 实际档. 单进程 portal, nginx worker=512,
#                 关 LFS / 关 forgejo runner / 关 docker compose 上层服务,
#                 systemd MemoryHigh 严格收紧
#   small  4-6G : 4C4G 续费档. portal 2 进程, nginx worker=1024
#   medium 6-12G: 4C8G 异变档. portal 4 进程, runner 可开
#   large  12-24G: 不应该出现在域名机, 但兼容
#   xlarge >=24G: 同上, 兼容
#
# 输出:
#   1. /data/guanghulab/.env.tune — bootstrap source 用
#   2. /opt/guanghulab/_logs/tune-decision-*.json — 决策回执
#
# ⚠️  当前 .env.tune 真实作用域:
#   bootstrap.sh source 这个文件后, 当前**真正影响行为的字段**:
#     - PORTAL_INSTANCES   → pm2 起 portal 时的 instances 数
#     - NGINX_WORKER_CONN  → 渲染 nginx/guanghulab.conf 时的 worker_connections
#     - FORGEJO_ENABLED    → bootstrap 是否在 /data/guanghulab/forgejo/ 起 forgejo
#                              (PR-6 才真正用, 这里只是预留)
#     - LFS_ENABLED        → 是否在 nginx 里开 client_max_body_size 大上限
#                              (PR-6 才真正用)
#     - SWAP_GB            → bootstrap 是否要建/扩 swap 文件
#   其他字段是档位决策的快照, 落档便于霜砚追溯.
# ════════════════════════════════════════════════════════════════

set -euo pipefail

ENV_FILE="${ENV_FILE:-/opt/guanghulab/_logs/server-env.json}"
DATA_ROOT="${DATA_ROOT:-/data/guanghulab}"
DEPLOY_ROOT="${DEPLOY_ROOT:-/opt/guanghulab}"

if [ ! -f "$ENV_FILE" ]; then
  echo "❌ [tune] 找不到 $ENV_FILE, 请先跑 detect-env.sh" >&2
  exit 1
fi
if ! command -v jq >/dev/null 2>&1; then
  echo "❌ [tune] 需要 jq (apt-get install -y jq)" >&2
  exit 1
fi

SIZE_TIER="$(jq -r '.compute.size_tier' "$ENV_FILE")"
MEM_MB="$(jq -r '.compute.memory_total_mb' "$ENV_FILE")"
SWAP_MB="$(jq -r '.compute.swap_total_mb' "$ENV_FILE")"
CPU="$(jq -r '.compute.cpu_count' "$ENV_FILE")"

# ─── 档位 → 参数表 ────────────────────────────────────────────
case "$SIZE_TIER" in
  tiny)
    PORTAL_INSTANCES="1"
    PORTAL_MAX_MEMORY_MB="384"        # pm2 重启阈值 (单进程)
    NGINX_WORKER_CONN="512"
    NGINX_WORKER_PROCESSES="1"        # 2C2G 单 worker 就够
    FORGEJO_ENABLED="false"           # 2C2G 跑不下 forgejo + portal
    LFS_ENABLED="false"
    NEED_SWAP_GB="1"                  # 内存不够, 给 1G swap 兜底
    SYSTEMD_PORTAL_HIGH_MB="500"
    SYSTEMD_PORTAL_MAX_MB="700"
    NOTE="2C2G 实际档. portal 单进程, forgejo/lfs 关. 任何全量 git push 走灯塔, 这里不揽."
    ;;
  small)
    PORTAL_INSTANCES="2"
    PORTAL_MAX_MEMORY_MB="512"
    NGINX_WORKER_CONN="1024"
    NGINX_WORKER_PROCESSES="2"
    FORGEJO_ENABLED="false"
    LFS_ENABLED="false"
    NEED_SWAP_GB="0"                  # 4G 起够用, 不强制 swap
    SYSTEMD_PORTAL_HIGH_MB="800"
    SYSTEMD_PORTAL_MAX_MB="1200"
    NOTE="4C4G 续费档. portal 双进程, 仍不开 forgejo (forgejo 留在灯塔)."
    ;;
  medium)
    PORTAL_INSTANCES="4"
    PORTAL_MAX_MEMORY_MB="768"
    NGINX_WORKER_CONN="2048"
    NGINX_WORKER_PROCESSES="auto"
    FORGEJO_ENABLED="true"
    LFS_ENABLED="true"
    NEED_SWAP_GB="0"
    SYSTEMD_PORTAL_HIGH_MB="2000"
    SYSTEMD_PORTAL_MAX_MB="3000"
    NOTE="4C8G+ 档. 可选 forgejo + lfs. 这台升到这档说明冰朔升配了, 顺带把灯塔合并意图打开."
    ;;
  large|xlarge)
    PORTAL_INSTANCES="4"
    PORTAL_MAX_MEMORY_MB="1024"
    NGINX_WORKER_CONN="4096"
    NGINX_WORKER_PROCESSES="auto"
    FORGEJO_ENABLED="true"
    LFS_ENABLED="true"
    NEED_SWAP_GB="0"
    SYSTEMD_PORTAL_HIGH_MB="3500"
    SYSTEMD_PORTAL_MAX_MB="6000"
    NOTE="超规格. 资源不再紧张, 全量功能开."
    ;;
  *)
    echo "❌ [tune] 未知 size_tier=$SIZE_TIER" >&2
    exit 1
    ;;
esac

# 已有 swap >= 1G 时, 不再强制再加 (避免重复建 swapfile)
if [ "$NEED_SWAP_GB" = "1" ] && [ "$SWAP_MB" -ge 1024 ]; then
  NEED_SWAP_GB="0"
fi

# ─── 写 .env.tune ─────────────────────────────────────────────
TUNE_FILE="$DATA_ROOT/.env.tune"
mkdir -p "$(dirname "$TUNE_FILE")"
cat > "$TUNE_FILE" <<EOF
# Generated by domain-cn/tune-from-env.sh @ $(date -u +%Y-%m-%dT%H:%M:%SZ)
# 档位: $SIZE_TIER (基于 ${MEM_MB}MB 内存 / ${CPU} 核 / swap ${SWAP_MB}MB)
# 注: $NOTE
#
# ⚠️  作用域说明:
#   - bootstrap.sh source 这个文件
#   - PORTAL_INSTANCES / NGINX_WORKER_CONN / FORGEJO_ENABLED /
#     LFS_ENABLED / NEED_SWAP_GB 真正影响行为
#   - 其他字段是档位决策快照, 给霜砚 / 冰朔追溯
SIZE_TIER=$SIZE_TIER
PORTAL_INSTANCES=$PORTAL_INSTANCES
PORTAL_MAX_MEMORY_MB=$PORTAL_MAX_MEMORY_MB
NGINX_WORKER_CONN=$NGINX_WORKER_CONN
NGINX_WORKER_PROCESSES=$NGINX_WORKER_PROCESSES
FORGEJO_ENABLED=$FORGEJO_ENABLED
LFS_ENABLED=$LFS_ENABLED
NEED_SWAP_GB=$NEED_SWAP_GB
SYSTEMD_PORTAL_HIGH_MB=$SYSTEMD_PORTAL_HIGH_MB
SYSTEMD_PORTAL_MAX_MB=$SYSTEMD_PORTAL_MAX_MB
EOF
chmod 644 "$TUNE_FILE"

# ─── 决策回执 ─────────────────────────────────────────────────
TS="$(date -u +%Y%m%d-%H%M%S)"
RECEIPT="$DEPLOY_ROOT/_logs/tune-decision-$TS.json"
mkdir -p "$DEPLOY_ROOT/_logs"
cat > "$RECEIPT" <<EOF
{
  "_sovereign": "TCS-0002∞ · 国作登字-2026-A-00037559",
  "_purpose": "domain-cn tune decision",
  "decided_at": "$(date -u +%Y-%m-%dT%H:%M:%SZ)",
  "input": {
    "size_tier": "$SIZE_TIER",
    "memory_mb": $MEM_MB,
    "swap_mb": $SWAP_MB,
    "cpu_count": $CPU
  },
  "decision": {
    "PORTAL_INSTANCES": $PORTAL_INSTANCES,
    "PORTAL_MAX_MEMORY_MB": $PORTAL_MAX_MEMORY_MB,
    "NGINX_WORKER_CONN": $NGINX_WORKER_CONN,
    "NGINX_WORKER_PROCESSES": "$NGINX_WORKER_PROCESSES",
    "FORGEJO_ENABLED": $FORGEJO_ENABLED,
    "LFS_ENABLED": $LFS_ENABLED,
    "NEED_SWAP_GB": $NEED_SWAP_GB,
    "SYSTEMD_PORTAL_HIGH_MB": $SYSTEMD_PORTAL_HIGH_MB,
    "SYSTEMD_PORTAL_MAX_MB": $SYSTEMD_PORTAL_MAX_MB
  },
  "note": "$NOTE",
  "tune_file": "$TUNE_FILE"
}
EOF

echo "═══════════════════════════════════════════════════════════"
echo "  [tune · domain-cn] 动态调优决策"
echo "═══════════════════════════════════════════════════════════"
echo "  档位:           $SIZE_TIER  (${MEM_MB}MB / ${CPU} 核 / swap ${SWAP_MB}MB)"
echo "  Portal 进程:    $PORTAL_INSTANCES (单进程上限 ${PORTAL_MAX_MEMORY_MB}MB)"
echo "  Nginx worker:   $NGINX_WORKER_PROCESSES 进程 / $NGINX_WORKER_CONN 连接"
echo "  Forgejo:        $FORGEJO_ENABLED"
echo "  Git LFS:        $LFS_ENABLED"
echo "  需要建 swap:    $NEED_SWAP_GB G"
echo "  systemd MemHi:  ${SYSTEMD_PORTAL_HIGH_MB}MB / Max ${SYSTEMD_PORTAL_MAX_MB}MB"
echo "  注:             $NOTE"
echo "  写入:           $TUNE_FILE"
echo "  回执:           $RECEIPT"
echo "═══════════════════════════════════════════════════════════"