#!/usr/bin/env bash
# lib.sh —— 共用函数库，被所有备份脚本 source

# ---------- 日志 ----------
log_info()  { echo "[$(date '+%Y-%m-%d %H:%M:%S')] [INFO]  $*"; }
log_warn()  { echo "[$(date '+%Y-%m-%d %H:%M:%S')] [WARN]  $*" >&2; }
log_error() { echo "[$(date '+%Y-%m-%d %H:%M:%S')] [ERROR] $*" >&2; }
log_ok()    { echo "[$(date '+%Y-%m-%d %H:%M:%S')] [OK]    $*"; }

# ---------- 默认值 ----------
: "${BACKUP_DIR:=/backup}"
: "${MYSQL_HOST:=127.0.0.1}"
: "${MYSQL_PORT:=3306}"
: "${PG_HOST:=127.0.0.1}"
: "${PG_PORT:=5432}"
: "${BACKUP_AWS_REGION:=ap-southeast-1}"
: "${AWS_PROFILE:=backup}"

# ---------- 通知（Webhook，可选） ----------
notify() {
    local level="$1"
    local msg="$2"
    log_info "[NOTIFY] ${level}: ${msg}"
    if [ -n "${NOTIFY_WEBHOOK_URL:-}" ]; then
        curl -fsS -X POST "${NOTIFY_WEBHOOK_URL}" \
            -H 'Content-Type: application/json' \
            -d "{\"level\":\"${level}\",\"msg\":$(printf '%s' "${msg}" | python3 -c 'import json,sys; print(json.dumps(sys.stdin.read()))')}" \
            --max-time 10 || true
    fi
}

# ---------- age 加密 ----------
# 用法: age_encrypt <input_file> <output_file>
age_encrypt() {
    local src="$1"
    local dst="$2"
    local pubkey_file="${AGE_PUBLIC_KEY_FILE:-/etc/age-public.txt}"
    if [ ! -f "${pubkey_file}" ]; then
        log_error "age 公钥文件不存在: ${pubkey_file}"
        return 1
    fi
    age --encrypt --recipient "$(cat "${pubkey_file}")" -o "${dst}" "${src}"
}

# ---------- S3 上传 ----------
# 用法: s3_upload <local_file> <s3_path_suffix>
s3_upload() {
    local src="$1"
    local suffix="$2"
    local dst="s3://${BACKUP_S3_BUCKET}/${BACKUP_S3_PREFIX}/${suffix}"
    log_info "上传 $(basename "${src}") → ${dst}"
    AWS_PROFILE="${AWS_PROFILE}" aws s3 cp \
        --no-progress \
        --storage-class STANDARD_IA \
        "${src}" "${dst}"
    log_ok "上传完成: ${dst}"
}

# ---------- 加密并上传 ----------
# 用法: encrypt_and_upload <input_file> <s3_suffix>
encrypt_and_upload() {
    local src="$1"
    local suffix="$2"
    local enc_file="${BACKUP_DIR}/encrypt/$(basename "${src}").age"

    mkdir -p "${BACKUP_DIR}/encrypt"
    log_info "age 加密: ${src}"
    age_encrypt "${src}" "${enc_file}"

    s3_upload "${enc_file}" "${suffix}.age"

    # 删除本地加密临时文件（原始文件由调用方管理）
    rm -f "${enc_file}"
}

# ---------- MySQL 连接测试 ----------
mysql_ping() {
    mysql \
        --host="${MYSQL_HOST}" \
        --port="${MYSQL_PORT}" \
        --user="${MYSQL_USER:-root}" \
        --password="${MYSQL_PASSWORD}" \
        --connect-timeout=5 \
        -e "SELECT 1" > /dev/null 2>&1
}

# ---------- PostgreSQL 连接测试 ----------
pg_ping() {
    PGPASSWORD="${PG_PASSWORD:-}" pg_isready \
        --host="${PG_HOST}" \
        --port="${PG_PORT}" \
        --username="${PG_USER:-postgres}" \
        --quiet 2>&1
}

# ---------- 计时工具 ----------
timer_start() { date +%s; }
timer_elapsed() {
    local start="$1"
    local end
    end=$(date +%s)
    echo $(( end - start ))
}
format_duration() {
    local secs="$1"
    local h=$(( secs / 3600 ))
    local m=$(( (secs % 3600) / 60 ))
    local s=$(( secs % 60 ))
    printf '%dh %dm %ds' "${h}" "${m}" "${s}"
}