import Database from 'better-sqlite3';
import { mkdirSync } from 'fs';
import path from 'path';
import { sortableIso, stampRulesDate } from './kept-rules';

// AUTOFIRMER_DB lets several instances share one checkout, each with its own
// database. It is read once, at module load — schema creation and seeding are
// import side effects — so it must be in the environment at process start.
const DB_PATH = process.env.AUTOFIRMER_DB
    ? path.resolve(process.env.AUTOFIRMER_DB)
    : path.join(process.cwd(), 'autotrader.sqlite');

mkdirSync(path.dirname(DB_PATH), { recursive: true });
const db = new Database(DB_PATH);

db.pragma('foreign_keys = ON');
// Timeout first: every later statement, including the journal switch below,
// waits out a concurrent holder instead of failing with SQLITE_BUSY.
db.pragma('busy_timeout = 5000');
// WAL is best-effort. Switching journal mode needs the file to itself, and
// `next build` imports this module from several workers while the live server
// still holds the same file — a hard failure here fails the whole build.
try {
    db.pragma('journal_mode = WAL');
} catch {
    // Another connection holds the file; keep its journal mode.
}

db.exec(`
    CREATE TABLE IF NOT EXISTS instruments (
        symbol  TEXT    PRIMARY KEY,
        enabled INTEGER NOT NULL DEFAULT 1
    );
`);

// ── Machine-owned firm state ─────────────────────────────────────────────────
//
// Firms and account types themselves come from the master catalog (see
// lib/firm-catalog.ts) and are cached as one JSON blob in `settings`. These two
// tables hold the parts that are genuinely per-machine and must survive the
// catalog changing underneath them.
//
// Both reference firm ids as plain TEXT with NO foreign key on purpose. This
// file sets `foreign_keys = ON`, so an ON DELETE CASCADE here would wipe the
// Tradovate credentials the moment a firm was removed on the master — and
// mirroring master's deletions is routine, not exceptional. They must be
// orphan-tolerant: a firm that disappears and comes back finds its credentials
// and assignments still here.
db.exec(`
    CREATE TABLE IF NOT EXISTS firm_credentials (
        firm_id    TEXT PRIMARY KEY,
        firm_name  TEXT NOT NULL,
        username   TEXT NOT NULL,
        password   TEXT NOT NULL,
        updated_at TEXT NOT NULL
    );

    CREATE TABLE IF NOT EXISTS account_assignments (
        account_id      INTEGER PRIMARY KEY,
        firm_id         TEXT    NOT NULL,
        account_type_id TEXT,
        manual          INTEGER NOT NULL DEFAULT 0,
        resolved_at     TEXT    NOT NULL
    );
`);

// The legacy `firms`, `account_configs` and `firm_banned_symbols` tables are
// dead: firms now come from the master catalog. They are left on disk rather
// than dropped because `firms` is the only table that ever held plaintext
// Tradovate credentials, and a silent DROP would be unrecoverable if this
// change had to be rolled back. Safe to drop by hand once it has stuck.

// Migration: TopstepX firms authenticate with an API key instead of a
// password. Kept in the same table so re-keying and reconciliation treat both
// platforms alike; a Tradovate row simply leaves it blank.
try {
    db.exec("ALTER TABLE firm_credentials ADD COLUMN api_key TEXT NOT NULL DEFAULT ''");
} catch {
    // Column already exists
}

// Migration: each account's rules date — which of its account type's rule
// sets it trades on (lib/kept-rules.ts): an account dated before a firm's
// rule change keeps the rules from before it. Written when this machine first
// records the account (or from a restored backup), lowered to the broker's
// evidence of when the account opened, or set by hand (rules_date_manual,
// which evidence never moves). Every writer stores a toISOString() UTC
// string, so string order is time order.
//
// The run that adds the column dates every existing row at the migration
// time, never NULL: no account changes rules merely because its machine
// updated. The resolver then lowers those auto dates to the broker's
// evidence, so an account the evidence shows opened before a rule change
// goes back to the old rules. Column and backfill commit together, so
// `next build` workers racing the migration can't leave rows undated.

/** The date an undated row gets: now, but never before the catalog's last
 *  change — lib/kept-rules.ts stampRulesDate's floor (every build keeps
 *  settings.catalog_updated_at current), so a machine whose clock runs
 *  behind can't backdate an account first seen after a rule change into the
 *  rule set that change closed. Call inside the writing transaction. */
function undatedRowsDate(): string {
    let catalogUpdatedAt: string | null = null;
    try {
        const row = db.prepare("SELECT value FROM settings WHERE key = 'catalog_updated_at'").get() as { value?: unknown } | undefined;
        if (typeof row?.value === 'string') catalogUpdatedAt = row.value;
    } catch {
        // No settings table yet: a fresh database, with no rows to date.
    }
    return stampRulesDate(Date.now(), null, catalogUpdatedAt);
}

try {
    db.transaction(() => {
        db.exec('ALTER TABLE account_assignments ADD COLUMN rules_date TEXT');
        db.prepare('UPDATE account_assignments SET rules_date = ? WHERE rules_date IS NULL').run(undatedRowsDate());
    }).immediate();
} catch {
    // Column already exists
}
try {
    db.exec('ALTER TABLE account_assignments ADD COLUMN rules_date_manual INTEGER NOT NULL DEFAULT 0');
} catch {
    // Column already exists
}
// Rows an older build wrote after that run have no date: it keeps serving
// between a build's migration and the restart, and comes back in a rollback,
// and its INSERT has no rules_date. Dated the same way at every start, so no
// row stays undated (current rules forever, with no date to set by hand).
try {
    db.transaction(() => {
        db.prepare('UPDATE account_assignments SET rules_date = ? WHERE rules_date IS NULL').run(undatedRowsDate());
    }).immediate();
} catch {
    // No rules_date column — the migration above failed; nothing to date.
}

// ── Firm credentials ─────────────────────────────────────────────────────────

export interface FirmCredentialRow {
    firm_id: string;
    firm_name: string;
    username: string;
    password: string;
    api_key: string;
    updated_at: string;
}

export function getCredentials(firmId: string): { username: string; password: string; apiKey: string } | undefined {
    const row = db.prepare('SELECT username, password, api_key FROM firm_credentials WHERE firm_id = ?').get(firmId) as
        { username: string; password: string; api_key: string } | undefined;
    if (!row) return undefined;
    return { username: row.username, password: row.password, apiKey: row.api_key };
}

export function listCredentials(): FirmCredentialRow[] {
    return db.prepare('SELECT * FROM firm_credentials').all() as FirmCredentialRow[];
}

/** firm_name is stored alongside the id so credentials can be re-keyed by name
 *  if the master's database is ever rebuilt and the firms come back with new
 *  ids. See rekeyCredentialsByName in lib/firm-catalog.ts. */
export function setCredentials(firmId: string, firmName: string, username: string, password: string, apiKey = ''): void {
    db.prepare(`
        INSERT INTO firm_credentials (firm_id, firm_name, username, password, api_key, updated_at)
        VALUES (?, ?, ?, ?, ?, ?)
        ON CONFLICT(firm_id) DO UPDATE SET
            firm_name = excluded.firm_name,
            username = excluded.username,
            password = excluded.password,
            api_key = excluded.api_key,
            updated_at = excluded.updated_at
    `).run(firmId, firmName, username, password, apiKey, new Date().toISOString());
}

export function clearCredentials(firmId: string): boolean {
    return db.prepare('DELETE FROM firm_credentials WHERE firm_id = ?').run(firmId).changes > 0;
}

export function rekeyCredentials(fromFirmId: string, toFirmId: string): void {
    db.prepare('UPDATE firm_credentials SET firm_id = ? WHERE firm_id = ?').run(toFirmId, fromFirmId);
    db.prepare('UPDATE account_assignments SET firm_id = ? WHERE firm_id = ?').run(toFirmId, fromFirmId);
}

// ── Account type assignments ─────────────────────────────────────────────────

export interface AssignmentRow {
    account_id: number;
    firm_id: string;
    account_type_id: string | null;
    manual: number;   // 0 | 1
    resolved_at: string;
    /** ISO (toISOString). Which of the type's rule sets the account trades
     *  on; null only on a row an older build wrote after the migration —
     *  the current rules until evidence dates it. */
    rules_date: string | null;
    rules_date_manual: number;   // 0 | 1 — set by hand; evidence leaves it alone
}

/** An assignment as a backup carries it: one from a build before rules
 *  dates has neither column. */
export type BackupAssignmentRow = Omit<AssignmentRow, 'rules_date' | 'rules_date_manual'>
    & Partial<Pick<AssignmentRow, 'rules_date' | 'rules_date_manual'>>;

export function getAssignment(accountId: number): AssignmentRow | undefined {
    return db.prepare('SELECT * FROM account_assignments WHERE account_id = ?').get(accountId) as AssignmentRow | undefined;
}

export function listAssignments(firmId: string): AssignmentRow[] {
    return db.prepare('SELECT * FROM account_assignments WHERE firm_id = ?').all(firmId) as AssignmentRow[];
}

/** Every assignment, for the backup pushed to the master. */
export function listAllAssignments(): AssignmentRow[] {
    return db.prepare('SELECT * FROM account_assignments').all() as AssignmentRow[];
}

/** insertRulesDate dates a row this call creates (default now — callers pass
 *  lib/kept-rules.ts stampRulesDate). An existing row keeps its rules date
 *  and how it was set: re-resolving or re-pinning an account never makes it
 *  look new. Only a row with no date at all (an older build's) takes
 *  insertRulesDate. */
export function setAssignment(
    accountId: number,
    firmId: string,
    accountTypeId: string | null,
    manual: boolean,
    insertRulesDate?: string,
): void {
    const now = new Date().toISOString();
    db.prepare(`
        INSERT INTO account_assignments (account_id, firm_id, account_type_id, manual, resolved_at, rules_date)
        VALUES (?, ?, ?, ?, ?, ?)
        ON CONFLICT(account_id) DO UPDATE SET
            firm_id = excluded.firm_id,
            account_type_id = excluded.account_type_id,
            manual = excluded.manual,
            resolved_at = excluded.resolved_at,
            rules_date = COALESCE(account_assignments.rules_date, excluded.rules_date)
    `).run(accountId, firmId, accountTypeId, manual ? 1 : 0, now, insertRulesDate ?? now);
}

/** Writes an auto-resolved assignment, leaving any manual override alone.
 *  The `manual = 0` guard is what makes a user's pick stick across syncs. */
export function setAutoAssignment(
    accountId: number,
    firmId: string,
    accountTypeId: string | null,
    insertRulesDate?: string,
): void {
    const existing = getAssignment(accountId);
    if (existing?.manual === 1) return;
    setAssignment(accountId, firmId, accountTypeId, false, insertRulesDate);
}

/** Drops a manual pin but keeps the row — and with it the rules date, so
 *  unpinning can't make an old account look new. The auto-resolver takes the
 *  account back on its next pass. False when there is no row. */
export function unpinAssignment(accountId: number): boolean {
    return db.prepare('UPDATE account_assignments SET manual = 0, account_type_id = NULL, resolved_at = ? WHERE account_id = ?')
        .run(new Date().toISOString(), accountId).changes > 0;
}

/** Sets an account's rules date (an ISO toISOString() string); manual marks
 *  it set by hand, which broker evidence never moves. False when the account
 *  has no row. */
export function setRulesDate(accountId: number, iso: string, manual: boolean): boolean {
    return db.prepare('UPDATE account_assignments SET rules_date = ?, rules_date_manual = ? WHERE account_id = ?')
        .run(iso, manual ? 1 : 0, accountId).changes > 0;
}

/** Dates a row that has none (one an older build wrote) at `iso`; a dated
 *  row is left alone. */
export function stampMissingRulesDate(accountId: number, iso: string): void {
    db.prepare('UPDATE account_assignments SET rules_date = ? WHERE account_id = ? AND rules_date IS NULL').run(iso, accountId);
}

/** Moves an auto rules date earlier to `iso` (the broker's evidence of when
 *  the account opened, lib/kept-rules.ts openingEvidence); never later and
 *  never a date set by hand. Compared as strings, which is time order only
 *  because every rules date is a plain four-digit-year UTC toISOString()
 *  string (lib/kept-rules.ts sortableIso) — keep it that way. */
export function lowerAutoRulesDate(accountId: number, iso: string): void {
    db.prepare(`
        UPDATE account_assignments SET rules_date = ?
        WHERE account_id = ? AND rules_date_manual = 0 AND (rules_date IS NULL OR rules_date > ?)
    `).run(iso, accountId, iso);
}

/**
 * One backed-up assignment onto this machine, every column (both restore
 * paths: lib/backup-restore.ts, and scripts/seed-settings.js by hand). The
 * backup's rules date and its manual flag win when the backup has one; a
 * backup from an older build has none, so an existing row keeps its own and
 * a new row is dated now, at the restore.
 */
export function restoreAssignment(row: BackupAssignmentRow): void {
    const now = new Date().toISOString();
    const resolvedAt = typeof row.resolved_at === 'string' ? row.resolved_at : now;
    // Only a date that sorts as a string counts as the backup's (anything
    // else is restored like an older build's undated row).
    const rulesDate = typeof row.rules_date === 'string' ? sortableIso(Date.parse(row.rules_date)) : null;
    if (rulesDate) {
        db.prepare(`
            INSERT INTO account_assignments (account_id, firm_id, account_type_id, manual, resolved_at, rules_date, rules_date_manual)
            VALUES (?, ?, ?, ?, ?, ?, ?)
            ON CONFLICT(account_id) DO UPDATE SET
                firm_id = excluded.firm_id,
                account_type_id = excluded.account_type_id,
                manual = excluded.manual,
                resolved_at = excluded.resolved_at,
                rules_date = excluded.rules_date,
                rules_date_manual = excluded.rules_date_manual
        `).run(row.account_id, row.firm_id, row.account_type_id ?? null, row.manual === 1 ? 1 : 0, resolvedAt,
            rulesDate, row.rules_date_manual === 1 ? 1 : 0);
        return;
    }
    db.prepare(`
        INSERT INTO account_assignments (account_id, firm_id, account_type_id, manual, resolved_at, rules_date)
        VALUES (?, ?, ?, ?, ?, ?)
        ON CONFLICT(account_id) DO UPDATE SET
            firm_id = excluded.firm_id,
            account_type_id = excluded.account_type_id,
            manual = excluded.manual,
            resolved_at = excluded.resolved_at,
            rules_date = COALESCE(account_assignments.rules_date, excluded.rules_date)
    `).run(row.account_id, row.firm_id, row.account_type_id ?? null, row.manual === 1 ? 1 : 0, resolvedAt, now);
}

// ── Settings ─────────────────────────────────────────────────────────────────

db.exec(`
    CREATE TABLE IF NOT EXISTS settings (
        key   TEXT PRIMARY KEY,
        value TEXT NOT NULL
    );
`);

// Seed defaults if missing
const seedSetting = db.prepare(`INSERT OR IGNORE INTO settings (key, value) VALUES (?, ?)`);
seedSetting.run('max_concurrent_accounts', '5');
seedSetting.run('tick_interval_seconds', '60');
seedSetting.run('master_dashboard_url', 'https://master.juicerroom.com');
seedSetting.run('instance_name', '');
// The person uuid the master issues in its welcome. Stored, then presented on
// every hello/report — it is what lets a renamed instance_name stay the same
// person on the master. Never edited by hand.
seedSetting.run('instance_id', '');
seedSetting.run('trading_hours', 'full_cme');
// Solves the captchas the AutoBuyer runs into. Blank uses the key hardcoded in
// app/api/autobuyer/captcha; set this (or TWOCAPTCHA_API_KEY) to bill another
// account.
seedSetting.run('twocaptcha_api_key', '');
// Blank falls back to the proxy hardcoded in app/api/autobuyer/captcha; `none`
// solves without one.
seedSetting.run('twocaptcha_proxy', '');
// Bearer for PULLING an encrypted settings+credentials backup back from the
// master (its INSTANCE_BACKUP_TOKEN) — pushing needs no token and happens
// automatically. Blank = restore unavailable from this machine's UI.
seedSetting.run('master_backup_token', '');
// Routes broker traffic (TopstepX, Tradovate, Yahoo quotes) through a proxy:
// http(s):// or socks5(h)://, user:pass ok. The master link stays direct on
// purpose. Blank = direct. Takes effect on restart.
seedSetting.run('proxy_url', '');
// Mirrors the in-memory scheduler state so a restart can resume it.
seedSetting.run('scheduler_running', '0');
seedSetting.run('scheduler_action', 'Buy');
seedSetting.run('scheduler_symbol', 'NQ');
seedSetting.run('scheduler_stop_after_all', '0');

/** Wraps several writes in one transaction (used by the backup restore, so a
 *  half-applied backup cannot survive a crash). */
export function runInTransaction<T>(fn: () => T): T {
    return db.transaction(fn)();
}

/** The whole table, for the backup pushed to the master. */
export function listSettings(): Record<string, string> {
    const rows = db.prepare('SELECT key, value FROM settings').all() as { key: string; value: string }[];
    return Object.fromEntries(rows.map((r) => [r.key, r.value]));
}

export function getSetting(key: string): string | null {
    const row = db.prepare('SELECT value FROM settings WHERE key = ?').get(key) as { value: string } | undefined;
    return row?.value ?? null;
}

export function setSetting(key: string, value: string): void {
    db.prepare(`INSERT INTO settings (key, value) VALUES (?, ?) ON CONFLICT(key) DO UPDATE SET value = excluded.value`).run(key, value);
}

/** Seed a generated setting once, including across simultaneous server workers.
 *  Acquire the write lock before reading so they cannot choose different values. */
export function getOrCreateSetting(key: string, create: () => string): string {
    return db.transaction(() => {
        const saved = getSetting(key);
        if (saved?.trim()) return saved;
        const value = create();
        setSetting(key, value);
        return value;
    }).immediate();
}

// ── Instruments ──────────────────────────────────────────────────────────────

const SYMBOLS = ['NQ','MNQ','ES','MES','YM','MYM','RTY','M2K','GC','MGC','SI','CL','MCL','NG','ZB','ZN','ZF','6E','6J','6B'];

// Enabled on a fresh install. The rest still seed, so they can be switched on
// from the Instruments page, they just start off.
const DEFAULT_ENABLED = new Set(['NQ', 'GC', 'CL']);

// Seed instruments table if empty. Check and insert share one IMMEDIATE
// transaction: `next build` imports this module from several workers at once,
// and on a fresh machine they all saw an empty table and raced to insert the
// same symbols (UNIQUE constraint failed: instruments.symbol). OR IGNORE is
// the backstop if the lock is ever skipped.
db.transaction(() => {
    const instrCount = (db.prepare('SELECT COUNT(*) as count FROM instruments').get() as { count: number }).count;
    if (instrCount > 0) return;
    const ins = db.prepare('INSERT OR IGNORE INTO instruments (symbol, enabled) VALUES (?, ?)');
    for (const s of SYMBOLS) ins.run(s, DEFAULT_ENABLED.has(s) ? 1 : 0);
}).immediate();

export interface InstrumentRow {
    symbol: string;
    enabled: boolean;
}

export function getInstruments(): InstrumentRow[] {
    return (db.prepare('SELECT symbol, enabled FROM instruments ORDER BY symbol').all() as { symbol: string; enabled: number }[])
        .map((r) => ({ symbol: r.symbol, enabled: r.enabled === 1 }));
}

export function setInstrumentEnabled(symbol: string, enabled: boolean): boolean {
    const result = db.prepare('UPDATE instruments SET enabled = ? WHERE symbol = ?').run(enabled ? 1 : 0, symbol);
    return result.changes > 0;
}

// ── Daily P&L Cache ──────────────────────────────────────────────────────────

db.exec(`
    CREATE TABLE IF NOT EXISTS daily_pnl (
        account_id   INTEGER NOT NULL,
        account_name TEXT    NOT NULL,
        date         TEXT    NOT NULL,
        pnl          REAL    NOT NULL,
        PRIMARY KEY (account_id, date)
    );
`);

// Migration: the day's reported fees (TopstepX). The MLL reconstruction
// distributes off-book fee drift across days proportionally to these; rows
// from before the migration read 0 until the next fetch overwrites them.
try {
    db.exec('ALTER TABLE daily_pnl ADD COLUMN fees REAL NOT NULL DEFAULT 0');
} catch {
    // Column already exists
}

export function saveDailyPnL(accountId: number, accountName: string, entries: { date: string; pnl: number; fees?: number }[]): void {
    const ins = db.prepare('INSERT OR REPLACE INTO daily_pnl (account_id, account_name, date, pnl, fees) VALUES (?, ?, ?, ?, ?)');
    const txn = db.transaction(() => {
        for (const e of entries) {
            ins.run(accountId, accountName, e.date, e.pnl, e.fees ?? 0);
        }
    });
    txn();
}

export function loadDailyPnL(accountId: number): { date: string; pnl: number; fees: number }[] {
    return (db.prepare('SELECT date, pnl, fees FROM daily_pnl WHERE account_id = ? ORDER BY date').all(accountId) as { date: string; pnl: number; fees: number }[]);
}

// ── Fund Transactions Cache ───────────────────────────────────────────────────

db.exec(`
    CREATE TABLE IF NOT EXISTS fund_transactions (
        account_id   INTEGER NOT NULL,
        account_name TEXT    NOT NULL,
        date         TEXT    NOT NULL,
        amount       REAL    NOT NULL,
        PRIMARY KEY (account_id, date)
    );
`);

export function saveFundTransactions(accountId: number, accountName: string, entries: { date: string; amount: number }[]): void {
    const ins = db.prepare('INSERT OR REPLACE INTO fund_transactions (account_id, account_name, date, amount) VALUES (?, ?, ?, ?)');
    const txn = db.transaction(() => {
        for (const e of entries) ins.run(accountId, accountName, e.date, e.amount);
    });
    txn();
}

export function loadFundTransactions(accountId: number): { date: string; amount: number }[] {
    return db.prepare('SELECT date, amount FROM fund_transactions WHERE account_id = ? ORDER BY date').all(accountId) as { date: string; amount: number }[];
}

/** Deletes one day's fund transaction and sets account meta keys back in the
 *  same transaction (null deletes the key), so no reader sees the row gone
 *  with the cycle it started still in place. TopstepX's reconcile uses it to
 *  take back a day whose bookings netted to fee noise. */
export function dropFundTransaction(accountId: number, date: string, meta: { [key: string]: string | null }): void {
    const del = db.prepare('DELETE FROM account_meta WHERE account_id = ? AND key = ?');
    const txn = db.transaction(() => {
        db.prepare('DELETE FROM fund_transactions WHERE account_id = ? AND date = ?').run(accountId, date);
        for (const [key, value] of Object.entries(meta)) {
            if (value === null) del.run(accountId, key);
            else saveAccountMeta(accountId, key, value);
        }
    });
    txn();
}

// ── Account Meta ─────────────────────────────────────────────────────────────

db.exec(`
    CREATE TABLE IF NOT EXISTS account_meta (
        account_id INTEGER NOT NULL,
        key        TEXT    NOT NULL,
        value      TEXT    NOT NULL,
        PRIMARY KEY (account_id, key)
    );
`);

export function saveAccountMeta(accountId: number, key: string, value: string): void {
    db.prepare('INSERT OR REPLACE INTO account_meta (account_id, key, value) VALUES (?, ?, ?)').run(accountId, key, value);
}

export function loadAccountMeta(accountId: number, key: string): string | null {
    const row = db.prepare('SELECT value FROM account_meta WHERE account_id = ? AND key = ?').get(accountId, key) as { value: string } | undefined;
    return row?.value ?? null;
}

/** Where the cycle the latest fund transaction ended began, saved by the
 *  platform client as it moves last_fund_date forward — and only from a cycle
 *  start this instance saw, so the reporter's catch-up never judges a cycle
 *  whose older rows it lacks. fundDate = that cycle's fund date ('' for the
 *  account's first cycle); includesDay = whether that date's own trades were
 *  the cycle's (a deposit's are; a Tradovate withdrawal's only when it came
 *  before the day's first trade, which the reporter can't work out again). */
export function saveEndedCycleStart(accountId: number, start: { fundDate: string; includesDay: boolean }): void {
    saveAccountMeta(accountId, 'ended_cycle_start', JSON.stringify(start));
}

/** null when this instance never saw the ended cycle start: a new instance
 *  or a wipe (which clears it with the rest of the meta), or TopstepX's
 *  first-check lump. */
export function loadEndedCycleStart(accountId: number): { fundDate: string; includesDay: boolean } | null {
    const raw = loadAccountMeta(accountId, 'ended_cycle_start');
    if (raw === null) return null;
    try {
        const { fundDate, includesDay } = JSON.parse(raw) as { fundDate?: unknown; includesDay?: unknown };
        return typeof fundDate === 'string' && typeof includesDay === 'boolean' ? { fundDate, includesDay } : null;
    } catch {
        return null;
    }
}

/** Deletes every cached row for an account — daily P&L, fund transactions and
 *  meta — so the next report fetch rebuilds it from scratch. Rows older than
 *  the report's 28-day window are gone for good; that is the point (stale
 *  pre-roll dates), but it is why callers confirm first. */
/** account_meta keys a wipe leaves in place (see wipeAccountData). */
const WIPE_KEEPS = ['cash_baseline', 'roll_base', 'history_hold', 'wipe_fund_sig', 'inferred_account_size'];

export function wipeAccountData(accountId: number): void {
    const txn = db.transaction(() => {
        db.prepare('DELETE FROM daily_pnl WHERE account_id = ?').run(accountId);
        db.prepare('DELETE FROM fund_transactions WHERE account_id = ?').run(accountId);
        // History goes; what guards the rebuild stays — the balance baseline
        // and roll base a Cash History vouched for, the wipe's own hold and
        // pre-wipe fund signature — and the resolver's inferred size, which
        // nothing in the rebuilt history can infer again.
        db.prepare(`DELETE FROM account_meta WHERE account_id = ? AND key NOT IN (${WIPE_KEEPS.map(() => '?').join(', ')})`)
            .run(accountId, ...WIPE_KEEPS);
    });
    txn();
}

// ── AutoBuyer captures ───────────────────────────────────────────────────────

db.exec(`
    CREATE TABLE IF NOT EXISTS autobuyer_captures (
        id          INTEGER PRIMARY KEY AUTOINCREMENT,
        url         TEXT    NOT NULL,
        title       TEXT    NOT NULL DEFAULT '',
        html        TEXT    NOT NULL,
        viewport    TEXT    NOT NULL DEFAULT '{}',
        elements    TEXT    NOT NULL DEFAULT '[]',
        captured_at INTEGER NOT NULL
    );
`);

export interface CaptureRow {
    id: number;
    url: string;
    title: string;
    html: string;
    viewport: string;   // JSON ViewportMetrics
    elements: string;   // JSON ElementPosition[]
    captured_at: number;
}

/** Number of captures kept on disk — the extension overwrites constantly, so only
 *  a short tail is useful and an unbounded table would grow by megabytes a minute. */
const CAPTURE_HISTORY = 5;

export function saveCapture(c: Omit<CaptureRow, 'id'>): void {
    db.prepare(
        'INSERT INTO autobuyer_captures (url, title, html, viewport, elements, captured_at) VALUES (?, ?, ?, ?, ?, ?)'
    ).run(c.url, c.title, c.html, c.viewport, c.elements, c.captured_at);

    db.prepare(`
        DELETE FROM autobuyer_captures
        WHERE id NOT IN (SELECT id FROM autobuyer_captures ORDER BY id DESC LIMIT ?)
    `).run(CAPTURE_HISTORY);
}

export function getLatestCapture(): CaptureRow | undefined {
    return db.prepare('SELECT * FROM autobuyer_captures ORDER BY id DESC LIMIT 1').get() as CaptureRow | undefined;
}

export function clearCaptures(): void {
    db.prepare('DELETE FROM autobuyer_captures').run();
}

// ── AutoBuyer locate/click requests ──────────────────────────────────────────
//
// The Python clicker can't see inside Chrome, and the extension can't move the
// mouse. So they meet here: Python enqueues "where is <selector>?", the extension
// focuses the tab, measures the element and writes back desktop coordinates.

db.exec(`
    CREATE TABLE IF NOT EXISTS autobuyer_locate (
        id          INTEGER PRIMARY KEY AUTOINCREMENT,
        selector    TEXT    NOT NULL,
        match_index INTEGER NOT NULL DEFAULT 0,
        url_pattern TEXT    NOT NULL DEFAULT '',
        status      TEXT    NOT NULL DEFAULT 'pending',
        result      TEXT,
        error       TEXT,
        created_at  INTEGER NOT NULL,
        resolved_at INTEGER
    );
`);

export interface LocateRow {
    id: number;
    selector: string;
    match_index: number;
    url_pattern: string;
    open_url: string;
    navigate_url: string;
    options: string;      // JSON, per-request extras (scroll parameters, ...)
    status: 'pending' | 'claimed' | 'done' | 'error';
    result: string | null;
    error: string | null;
    created_at: number;
    resolved_at: number | null;
}

const LOCATE_HISTORY = 20;

export function createLocateRequest(selector: string, matchIndex: number, urlPattern: string, openUrl = '', navigateUrl = '', options = '{}'): LocateRow {
    const res = db.prepare(
        'INSERT INTO autobuyer_locate (selector, match_index, url_pattern, open_url, navigate_url, options, created_at) VALUES (?, ?, ?, ?, ?, ?, ?)'
    ).run(selector, matchIndex, urlPattern, openUrl, navigateUrl, options, Date.now());

    db.prepare(`
        DELETE FROM autobuyer_locate
        WHERE id NOT IN (SELECT id FROM autobuyer_locate ORDER BY id DESC LIMIT ?)
    `).run(LOCATE_HISTORY);

    return db.prepare('SELECT * FROM autobuyer_locate WHERE id = ?').get(res.lastInsertRowid) as LocateRow;
}

export function getLocateRequest(id: number): LocateRow | undefined {
    return db.prepare('SELECT * FROM autobuyer_locate WHERE id = ?').get(id) as LocateRow | undefined;
}

export function countPendingLocate(): number {
    const row = db.prepare("SELECT COUNT(*) AS n FROM autobuyer_locate WHERE status = 'pending'").get() as { n: number };
    return row.n;
}

/** Hand the oldest pending request to the extension, marking it claimed so a
 *  slow round-trip doesn't cause the same click to be served twice. */
export function claimLocateRequest(): LocateRow | undefined {
    const row = db.prepare("SELECT * FROM autobuyer_locate WHERE status = 'pending' ORDER BY id LIMIT 1").get() as LocateRow | undefined;
    if (!row) return undefined;
    db.prepare("UPDATE autobuyer_locate SET status = 'claimed' WHERE id = ?").run(row.id);
    return { ...row, status: 'claimed' };
}

export function resolveLocateRequest(id: number, result: unknown | null, error: string | null): void {
    db.prepare('UPDATE autobuyer_locate SET status = ?, result = ?, error = ?, resolved_at = ? WHERE id = ?')
        .run(error ? 'error' : 'done', result ? JSON.stringify(result) : null, error, Date.now(), id);
}

// ── AutoBuyer automation runs ────────────────────────────────────────────────
//
// The dashboard queues a run; the Python runner claims it and works through the
// steps, reporting progress back so the page can show what is happening.

db.exec(`
    CREATE TABLE IF NOT EXISTS autobuyer_runs (
        id            INTEGER PRIMARY KEY AUTOINCREMENT,
        automation_id TEXT    NOT NULL,
        status        TEXT    NOT NULL DEFAULT 'queued',
        step_index    INTEGER NOT NULL DEFAULT 0,
        total_steps   INTEGER NOT NULL DEFAULT 0,
        log           TEXT    NOT NULL DEFAULT '[]',
        inputs        TEXT    NOT NULL DEFAULT '{}',
        error         TEXT,
        created_at    INTEGER NOT NULL,
        updated_at    INTEGER NOT NULL
    );
`);

// Migration: free-form per-request options, so a new kind of request doesn't
// need a new column each time.
try {
    db.exec("ALTER TABLE autobuyer_locate ADD COLUMN options TEXT NOT NULL DEFAULT '{}'");
} catch {
    // Column already exists
}

// Migration: the page to send the tab to before locating.
try {
    db.exec("ALTER TABLE autobuyer_locate ADD COLUMN navigate_url TEXT NOT NULL DEFAULT ''");
} catch {
    // Column already exists
}

// Migration: the page to open when no tab matches the pattern.
try {
    db.exec("ALTER TABLE autobuyer_locate ADD COLUMN open_url TEXT NOT NULL DEFAULT ''");
} catch {
    // Column already exists
}

// Migration: per-run inputs the user set on the dashboard.
try {
    db.exec("ALTER TABLE autobuyer_runs ADD COLUMN inputs TEXT NOT NULL DEFAULT '{}'");
} catch {
    // Column already exists
}

export type RunStatus = 'queued' | 'running' | 'done' | 'error' | 'cancelled';

export interface RunRow {
    id: number;
    automation_id: string;
    status: RunStatus;
    step_index: number;
    total_steps: number;
    log: string;      // JSON { at: number; step: string; ok: boolean; detail?: string }[]
    inputs: string;   // JSON Record<string, number>
    error: string | null;
    created_at: number;
    updated_at: number;
}

const RUN_HISTORY = 30;

export function createRun(automationId: string, totalSteps: number, inputs: Record<string, number> = {}): RunRow {
    const now = Date.now();
    const res = db.prepare(
        'INSERT INTO autobuyer_runs (automation_id, total_steps, inputs, created_at, updated_at) VALUES (?, ?, ?, ?, ?)'
    ).run(automationId, totalSteps, JSON.stringify(inputs), now, now);

    db.prepare(`
        DELETE FROM autobuyer_runs
        WHERE id NOT IN (SELECT id FROM autobuyer_runs ORDER BY id DESC LIMIT ?)
    `).run(RUN_HISTORY);

    return db.prepare('SELECT * FROM autobuyer_runs WHERE id = ?').get(res.lastInsertRowid) as RunRow;
}

export function getRun(id: number): RunRow | undefined {
    return db.prepare('SELECT * FROM autobuyer_runs WHERE id = ?').get(id) as RunRow | undefined;
}

export function getRecentRuns(limit = 5): RunRow[] {
    return db.prepare('SELECT * FROM autobuyer_runs ORDER BY id DESC LIMIT ?').all(limit) as RunRow[];
}

export function countActiveRuns(): number {
    const row = db.prepare("SELECT COUNT(*) AS n FROM autobuyer_runs WHERE status IN ('queued','running')").get() as { n: number };
    return row.n;
}

/** Grace period before a 'running' run with nobody behind it is written off.
 *  Long enough to cover the gap between the runner claiming a run and its next
 *  heartbeat reporting busy. */
const ORPHAN_GRACE_MS = 30_000;

/** Fail runs that were left mid-flight when their runner went away.
 *
 *  Only one run executes at a time, so a stale 'running' row blocks every future
 *  run — kill the daemon during a run (or restart it, which is the same thing)
 *  and nothing would ever be claimed again. The heartbeat says whether anything
 *  is actually executing: a runner that is gone, or up and idle, is not driving
 *  this run no matter what its status column claims.
 */
export function reapOrphanedRuns(): number {
    const hb = getRunnerHeartbeat();
    const alive = hb !== null && Date.now() - hb.at < RUNNER_TIMEOUT_MS;
    if (alive && hb!.busy) return 0;

    const now = Date.now();
    return db.prepare(`
        UPDATE autobuyer_runs
        SET status = 'error',
            error = 'the runner stopped while this run was in progress',
            updated_at = ?
        WHERE status = 'running' AND updated_at < ?
    `).run(now, now - ORPHAN_GRACE_MS).changes;
}

/** The runner takes the oldest queued run. Only one runs at a time — two
 *  processes driving the same physical mouse would interleave clicks. */
export function claimRun(): RunRow | undefined {
    reapOrphanedRuns();

    const running = db.prepare("SELECT 1 FROM autobuyer_runs WHERE status = 'running'").get();
    if (running) return undefined;

    const row = db.prepare("SELECT * FROM autobuyer_runs WHERE status = 'queued' ORDER BY id LIMIT 1").get() as RunRow | undefined;
    if (!row) return undefined;

    db.prepare("UPDATE autobuyer_runs SET status = 'running', updated_at = ? WHERE id = ?").run(Date.now(), row.id);
    return { ...row, status: 'running' };
}

export function appendRunLog(id: number, entry: unknown, stepIndex: number): void {
    const row = getRun(id);
    if (!row) return;
    let log: unknown[];
    try { log = JSON.parse(row.log); } catch { log = []; }
    log.push(entry);
    db.prepare('UPDATE autobuyer_runs SET log = ?, step_index = ?, updated_at = ? WHERE id = ?')
        .run(JSON.stringify(log), stepIndex, Date.now(), id);
}

export function finishRun(id: number, status: RunStatus, error: string | null): void {
    db.prepare('UPDATE autobuyer_runs SET status = ?, error = ?, updated_at = ? WHERE id = ?')
        .run(status, error, Date.now(), id);
}

/** Cancelling a queued run stops it starting; cancelling a running one is seen
 *  by the runner between steps. */
export function cancelRun(id: number): boolean {
    const row = getRun(id);
    if (!row || row.status === 'done' || row.status === 'error' || row.status === 'cancelled') return false;
    finishRun(id, 'cancelled', null);
    return true;
}

// ── Runner heartbeat ─────────────────────────────────────────────────────────
//
// The runner is a desktop process, so the server can't tell whether it's alive.
// It reports in every couple of seconds; if the beats stop, the dashboard greys
// out the buttons rather than queueing runs nobody will execute.

/** Three missed beats. Long enough to ride out a slow tick, short enough that a
 *  killed runner shows as offline before you press anything. */
export const RUNNER_TIMEOUT_MS = 7000;

/** The runner version this server's step vocabulary requires. A running process
 *  doesn't reload when the source changes, so an older one silently fails on
 *  steps it predates — the dashboard warns instead. */
export const RUNNER_EXPECTED_VERSION = '0.20.0';

export interface RunnerHeartbeat {
    at: number;
    host?: string;
    pid?: number;
    dryRun?: boolean;
    busy?: boolean;
    version?: string;
}

export function setRunnerHeartbeat(info: Omit<RunnerHeartbeat, 'at'>): void {
    setSetting('runner_heartbeat', JSON.stringify({ ...info, at: Date.now() }));
}

export function getRunnerHeartbeat(): RunnerHeartbeat | null {
    const raw = getSetting('runner_heartbeat');
    if (!raw) return null;
    try { return JSON.parse(raw) as RunnerHeartbeat; } catch { return null; }
}