#!/usr/bin/env bash

set -euo pipefail

: "${KAFKA_BIN:?请设置 KAFKA_BIN，例如 /opt/kafka/bin}"
: "${BOOTSTRAP:?请设置 BOOTSTRAP，例如 127.0.0.1:9092}"

RAW_TOPIC="${RAW_TOPIC:-agent-01-syslog-topic}"
TOPICS_CMD="${KAFKA_BIN}/kafka-topics.sh"
CONFIGS_CMD="${KAFKA_BIN}/kafka-configs.sh"

if [[ ! -x "${TOPICS_CMD}" ]] || [[ ! -x "${CONFIGS_CMD}" ]]; then
  echo "ERROR: ${KAFKA_BIN} 下缺少 kafka-topics.sh 或 kafka-configs.sh" >&2
  exit 1
fi

COMMON_ARGS=(--bootstrap-server "${BOOTSTRAP}")
if [[ -n "${COMMAND_CONFIG:-}" ]]; then
  COMMON_ARGS+=(--command-config "${COMMAND_CONFIG}")
fi

echo "检查原始 Topic：${RAW_TOPIC}"
RAW_INFO=$("${TOPICS_CMD}" "${COMMON_ARGS[@]}" --describe --topic "${RAW_TOPIC}")
printf '%s\n' "${RAW_INFO}"

PARTITIONS=$(printf '%s\n' "${RAW_INFO}" | awk '
  /PartitionCount:/ {
    for (i=1; i<=NF; i++) if ($i=="PartitionCount:") { print $(i+1); exit }
  }
')
REPLICAS=$(printf '%s\n' "${RAW_INFO}" | awk '
  /ReplicationFactor:/ {
    for (i=1; i<=NF; i++) if ($i=="ReplicationFactor:") { print $(i+1); exit }
  }
')

if [[ ! "${PARTITIONS}" =~ ^[1-9][0-9]*$ ]] || [[ ! "${REPLICAS}" =~ ^[1-9][0-9]*$ ]]; then
  echo "ERROR: 无法读取原始 Topic 的分区数或副本数" >&2
  exit 1
fi

SUFFIXES=("RETRY.1M" "RETRY.10M" "RETRY.1H" "DLT" "REPLAY" "STATS.MATERIALIZE")
RETENTIONS=(259200000 604800000 604800000 7776000000 604800000 604800000)

for i in 0 1 2 3 4 5; do
  TOPIC="${RAW_TOPIC}.${SUFFIXES[$i]}"
  echo "创建或确认 Topic：${TOPIC}"
  "${TOPICS_CMD}" "${COMMON_ARGS[@]}" \
    --create --if-not-exists \
    --topic "${TOPIC}" \
    --partitions "${PARTITIONS}" \
    --replication-factor "${REPLICAS}" \
    --config "retention.ms=${RETENTIONS[$i]}"

  "${CONFIGS_CMD}" "${COMMON_ARGS[@]}" \
    --alter --entity-type topics --entity-name "${TOPIC}" \
    --add-config "retention.ms=${RETENTIONS[$i]}"
done

echo "检查升级结果"
for SUFFIX in "${SUFFIXES[@]}"; do
  "${TOPICS_CMD}" "${COMMON_ARGS[@]}" --describe --topic "${RAW_TOPIC}.${SUFFIX}"
done

echo "PASS: Kafka Topic 已创建/确认；脚本未删除 Topic，也未修改消费组 offset。"