import { ensurePair, createMeta } from '../lib/validate.js';
import { fetchJson, BITBANK_API_BASE } from '../lib/http.js';
import { ok, fail } from '../lib/result.js';
import { formatSummary, formatTimestampJST } from '../lib/formatter.js';
import { getErrorMessage, isAbortError } from '../lib/error.js';
import { GetDepthOutputSchema } from '../src/schemas.js';
export interface GetDepthOptions { timeoutMs?: number; maxLevels?: number }
export default async function getDepth(
pair: string,
{ timeoutMs = 3000, maxLevels = 200 }: GetDepthOptions = {}
) {
const chk = ensurePair(pair);
if (!chk.ok) return fail(chk.error.message, chk.error.type);
const url = `${BITBANK_API_BASE}/${chk.pair}/depth`;
try {
const json: unknown = await fetchJson(url, { timeoutMs, retries: 2 });
const jsonObj = json as { data?: Record<string, unknown> };
const d = jsonObj?.data ?? {};
const asks = Array.isArray(d.asks) ? d.asks.slice(0, maxLevels) : [];
const bids = Array.isArray(d.bids) ? d.bids.slice(0, maxLevels) : [];
// 簡易サマリ（最良気配と件数）
const bestAsk = asks[0]?.[0] ?? null;
const bestBid = bids[0]?.[0] ?? null;
const mid = bestBid && bestAsk ? Number(((Number(bestBid) + Number(bestAsk)) / 2).toFixed(2)) : null;
const summary = formatSummary({
pair: chk.pair,
latest: mid ?? undefined,
extra: `levels: bids=${bids.length} asks=${asks.length}`,
});
// ゾーン自動推定（簡易）：各サイドの上位Nレベルで閾値以上を帯にする
function estimateZones(levels: Array<[number, number]>, side: 'bid' | 'ask'): Array<{ low: number; high: number; label: string; color?: string }> {
if (!levels.length) return [];
const qtys = levels.map(([, s]) => s);
const avg = qtys.reduce((a, b) => a + b, 0) / qtys.length;
const stdev = Math.sqrt(qtys.reduce((a, b) => a + Math.pow(b - avg, 2), 0) / qtys.length) || 0;
const thr = avg + stdev * 2; // 強めの閾値
const zones: Array<{ low: number; high: number; label: string; color?: string }> = [];
for (const [p, s] of levels) {
if (s >= thr) {
const pad = (p as number) * 0.001; // 0.1%幅
if (side === 'bid') zones.push({ low: (p as number) - pad, high: (p as number) + pad, label: 'bid wall', color: 'rgba(34,197,94,0.08)' });
else zones.push({ low: (p as number) - pad, high: (p as number) + pad, label: 'ask wall', color: 'rgba(249,115,22,0.08)' });
}
}
return zones.slice(0, 5); // 多すぎないように上位数本
}
const data = {
asks,
bids,
asks_over: d.asks_over,
asks_under: d.asks_under,
bids_over: d.bids_over,
bids_under: d.bids_under,
ask_market: d.ask_market,
bid_market: d.bid_market,
timestamp: Number(d.timestamp ?? d.timestamp_ms ?? Date.now()),
sequenceId:
d.sequenceId != null ? Number(d.sequenceId) :
d.sequence_id != null ? Number(d.sequence_id) :
undefined,
overlays: {
depth_zones: [
...estimateZones(bids.slice(0, 50).map(([p, s]: [unknown, unknown]) => [Number(p), Number(s)] as [number, number]), 'bid'),
...estimateZones(asks.slice(0, 50).map(([p, s]: [unknown, unknown]) => [Number(p), Number(s)] as [number, number]), 'ask'),
],
},
};
// タイムスタンプ付きテキスト出力
const text = [
`📸 ${formatTimestampJST(data.timestamp)}`,
'',
summary,
`板の層数: 買い ${bids.length}層 / 売り ${asks.length}層`,
mid ? `中値: ${mid.toLocaleString()}円` : '',
].filter(Boolean).join('\n');
const meta = createMeta(chk.pair);
return GetDepthOutputSchema.parse(ok(text, data as any, meta as any));
} catch (err: unknown) {
const isAbort = isAbortError(err);
const message = isAbort ? `タイムアウト (${timeoutMs}ms)` : getErrorMessage(err) || 'ネットワークエラー';
return GetDepthOutputSchema.parse(fail(message, isAbort ? 'timeout' : 'network')) as any;
}
}
