#!/usr/bin/env bash
# monitor-ai 健康检查兜底脚本
#
# 用途：当 monitor-ai 自身的健康检查失败时，通过 webhook 直接发送告警
# 部署：添加到 crontab，每 5 分钟执行一次
#
# crontab 配置：
#   */5 * * * * /root/docker/monitor-ai/scripts/monitor-watchdog.sh >> /var/log/monitor-watchdog.log 2>&1
#
# 日志文件：/var/log/monitor-watchdog.log（建议配合 logrotate）

set -euo pipefail

# ============================================================
# 配置
# ============================================================
HEALTH_URL="${MONITOR_HEALTH_URL:-https://monitor.tlyq.ai/api/health}"
TIMEOUT=10
MAX_RETRIES=2
RETRY_DELAY=5

# 企业微信 Webhook（从 .env 读取或使用环境变量）
MONITOR_DIR="/root/docker/monitor-ai"
if [[ -f "$MONITOR_DIR/.env" ]]; then
    # 从 .env 读取第一个启用的 webhook URL
    WEBHOOK_URL="${WEBHOOK_URL:-$(grep -E '^WEBHOOK_URL=' "$MONITOR_DIR/.env" 2>/dev/null | head -1 | cut -d= -f2-)}"
fi

# 如果没有配置 webhook，尝试从数据库读取
if [[ -z "${WEBHOOK_URL:-}" ]]; then
    DB_PATH="${MONITOR_DIR}/data/monitor.db"
    if [[ -f "$DB_PATH" ]]; then
        WEBHOOK_URL=$(sqlite3 "$DB_PATH" "SELECT webhook_url FROM alert_channels WHERE enabled=1 LIMIT 1;" 2>/dev/null || echo "")
    fi
fi

# 日志函数
log() {
    echo "[$(date '+%Y-%m-%d %H:%M:%S')] $1"
}

# ============================================================
# 健康检查
# ============================================================
check_health() {
    local attempt=0
    local http_code=""

    while [[ $attempt -lt $MAX_RETRIES ]]; do
        attempt=$((attempt + 1))

        http_code=$(curl -s -o /dev/null -w '%{http_code}' \
            --connect-timeout "$TIMEOUT" \
            --max-time "$TIMEOUT" \
            "$HEALTH_URL" 2>/dev/null) || http_code="000"

        if [[ "$http_code" == "200" ]]; then
            return 0
        fi

        if [[ $attempt -lt $MAX_RETRIES ]]; then
            log "健康检查失败 (HTTP $http_code)，${RETRY_DELAY}s 后重试..."
            sleep "$RETRY_DELAY"
        fi
    done

    return 1
}

# ============================================================
# 发送告警
# ============================================================
send_alert() {
    local message="$1"

    if [[ -z "${WEBHOOK_URL:-}" ]]; then
        log "WARNING: 未配置企业微信 Webhook URL，无法发送告警"
        return 1
    fi

    local payload
    payload=$(cat <<EOF
{
    "msgtype": "markdown",
    "markdown": {
        "content": "## ⚠️ monitor-ai 自身异常\n\n> 告警时间: $(date '+%Y-%m-%d %H:%M:%S')\n\n**健康检查地址**: ${HEALTH_URL}\n\n**失败原因**: ${message}\n\n**处理建议**: 请检查 monitor-ai 容器状态\n\n<font color=\"warning\">此告警由 monitor-watchdog 发送</font>"
    }
}
EOF
)

    local response
    response=$(curl -s -X POST \
        --connect-timeout 10 \
        --max-time 10 \
        -H "Content-Type: application/json" \
        -d "$payload" \
        "$WEBHOOK_URL" 2>&1)

    if [[ $? -eq 0 ]]; then
        log "告警已发送: $response"
    else
        log "WARNING: 告警发送失败: $response"
        return 1
    fi
}

# ============================================================
# 主逻辑
# ============================================================
main() {
    log "开始健康检查: $HEALTH_URL"

    if check_health; then
        log "健康检查通过 (HTTP 200)"
        exit 0
    fi

    log "ERROR: 健康检查失败，尝试发送告警..."
    send_alert "HTTP 健康检查失败，连续 ${MAX_RETRIES} 次请求均未返回 200"

    # 检查容器状态
    local container_status
    container_status=$(docker inspect -f '{{.State.Status}}' monitor-ai 2>/dev/null || echo "not_found")
    log "容器状态: $container_status"

    if [[ "$container_status" != "running" ]]; then
        log "ERROR: 容器未运行，尝试重启..."
        cd "$MONITOR_DIR" && docker compose up -d 2>&1 | while read -r line; do log "  $line"; done

        # 等待容器启动后再次检查
        sleep 10
        if check_health; then
            log "容器已重启并通过健康检查"
        else
            log "ERROR: 重启后健康检查仍然失败，请人工介入"
            send_alert "容器已重启，但健康检查仍然失败，请人工介入"
        fi
    fi
}

main "$@"