/**
 * 管理员列表：可读摘要 + Arco Tag 色号（与设计约定一致）。
 */
function parseDetail(raw) {
    if (raw == null || raw === '') return {}
    if (typeof raw === 'object') return raw
    try {
        return JSON.parse(raw)
    } catch {
        return { _text: String(raw) }
    }
}

const EVENT_META = {
    fetch: { label: '提取 IP', color: 'green' },
    invalidate: { label: '作废缓存', color: 'orangered' },
    fallback_direct: { label: '回退直连', color: 'red' },
    config_change: { label: '配置变更', color: 'arcoblue' }
}

function summarizeLogRow(record) {
    const event = record.event
    const d = parseDetail(record.detail)
    const lines = []

    if (event === 'fetch') {
        if (d.request_id) lines.push(`请求 ID：${d.request_id}`)
        if (d.code) lines.push(`接口状态：${d.code}`)
    } else if (event === 'invalidate') {
        if (d.reason) lines.push(`原因：${d.reason}`)
        if (d.message) lines.push(`说明：${d.message}`)
        if (d.code) lines.push(`错误码：${d.code}`)
        if (d.status) lines.push(`HTTP：${d.status}`)
    } else if (event === 'fallback_direct') {
        if (d.reason) lines.push(`触发原因：${d.reason}`)
        if (d.reason === 'exhausted_proxy_then_direct') {
            lines.push('多轮提取与经代理 POST 均未成功，已改直连对学校接口')
        } else if (d.message) {
            lines.push(`说明：${d.message}`)
        }
        if (d.after) lines.push(`阶段：${d.after}`)
        if (d.code) lines.push(`错误码：${d.code}`)
    } else if (event === 'config_change') {
        lines.push(`代理开关：${d.proxy_enabled === 1 ? '开' : '关'}`)
        if (d.area !== undefined) lines.push(`地区 area：「${d.area || '（空）'}」`)
        if (d.area_ex !== undefined) lines.push(`排除 area_ex：「${d.area_ex || '（空）'}」`)
        if (d.isp !== undefined) lines.push(`运营商 isp：${d.isp ?? '不限'}`)
        if (d.distinct_extract !== undefined) lines.push(`去重提取：${d.distinct_extract ? '是' : '否'}`)
        if (d.invalidate_cache) lines.push('已勾选清空服务端 IP 缓存')
        if (d.operator) lines.push(`操作者 UUID：${d.operator}`)
    } else if (Object.keys(d).length) {
        if (d._text) lines.push(String(d._text))
        else {
            Object.keys(d).slice(0, 6).forEach(k => {
                lines.push(`${k}：${typeof d[k] === 'object' ? JSON.stringify(d[k]) : d[k]}`)
            })
        }
    }

    let summary = lines.length ? lines.join('；') : '—'

    const meta = EVENT_META[event] || { label: event || '未知', color: 'gray' }
    const serverShown = record.server ? `节点 ${record.server}` : ''

    return {
        event_label: meta.label,
        event_color: meta.color,
        summary,
        detail_lines: lines,
        server_tip: serverShown || null,
        ...(record.server && record.deadline ? { deadline_tip: `${record.server} · ${record.deadline}` } : {})
    }
}

/**
 * 青果语义下的出口 IP（proxy_ip），非代理节点 host。
 */
function extractEgressIp(record) {
    const d = parseDetail(record.detail)
    const p = d.proxy_ip
    if (p === null || p === undefined || p === '') return null
    const s = String(p).trim()
    return /^(\d{1,3}\.){3}\d{1,3}$/.test(s) ? s : null
}

module.exports = {
    summarizeLogRow,
    parseDetail,
    EVENT_META,
    extractEgressIp
}