simulator-api 0.22.1

//! What flowed through a venue in a reroute population, on L1 and after the re-quote.
//!
//! Both sides come off the same record, so the comparison needs no control run. The L1 column
//! counts only legs among the re-quoted population, not the venue's whole L1 footprint.
//!
//! Nothing here does I/O.
//!
//! The two figures answer different questions. **Volume** is per-hop, valued by each hop's own
//! `inAmount`, so a leg crossing the venue twice counts at both. **Share** is per-leg
//! normalized, splitting each leg by `percent` across its route's venues, so the shares over a
//! direction sum to 100%.

use std::collections::BTreeMap;

use solana_address::Address;

use super::{LegRecord, Prices, Samples};
use crate::route_plan::{RouteHop, RoutePlan};

fn in_amount(hop: &RouteHop) -> Option<u128> {
    hop.swap_info.in_amount.as_ref()?.parse().ok()
}

/// The selector named a venue the stream never carried — a wrong address or a misspelling.
/// Reporting that as `$0` would be indistinguishable from a venue with no flow.
#[derive(Debug, thiserror::Error)]
pub enum RerouteReportError {
    #[error(
        "{asked} never appears in this stream.\nIt names {} venues; the busiest are {}.",
        .venues.len(),
        busiest(.venues),
    )]
    NothingMatched {
        /// The selector, as the caller gave it.
        asked: String,
        /// Every venue the stream's quotes did name, with its hop count.
        venues: Vec<(String, u64)>,
    },
}

const NAMED_IN_ERROR: usize = 8;

fn busiest(venues: &[(String, u64)]) -> String {
    let mut ranked: Vec<_> = venues.iter().collect();
    ranked.sort_unstable_by(|(a_label, a_hops), (b_label, b_hops)| {
        b_hops.cmp(a_hops).then_with(|| a_label.cmp(b_label))
    });
    ranked
        .iter()
        .take(NAMED_IN_ERROR)
        .map(|(label, hops)| format!("{label} ({hops})"))
        .collect::<Vec<_>>()
        .join(", ")
}

/// The venue under test, as the two sides can each name it.
///
/// Either key alone works; both is strictest. Resolving a program to its metis label is a
/// network lookup and not done here — pass the label you already hold.
#[derive(Clone, Default, Debug)]
pub struct Target {
    label: Option<String>,
    /// Paired with its base58, encoded once rather than per hop.
    program: Option<(Address, String)>,
}

impl Target {
    pub fn new(label: Option<String>, program: Option<Address>) -> Self {
        Self {
            label,
            program: program.map(|program| (program, program.to_string())),
        }
    }

    pub fn label(&self) -> Option<&str> {
        self.label.as_deref()
    }

    pub fn program(&self) -> Option<Address> {
        self.program.as_ref().map(|(program, _)| *program)
    }

    /// The quote plan names no program, so the label is the only key it can be matched on.
    pub fn claims_quoted(&self, hop: &RouteHop) -> bool {
        match &self.label {
            Some(label) => hop.label() == Some(label.as_str()),
            None => false,
        }
    }

    /// The program wins when given; the label fallback is what lets a label-only target measure
    /// this side instead of reporting zero.
    pub fn claims_fill(&self, hop: &RouteHop) -> bool {
        if let Some((_, key)) = &self.program {
            return hop.program.as_deref() == Some(key.as_str());
        }
        self.claims_quoted(hop)
    }

    fn describe(&self) -> String {
        if let Some(label) = &self.label {
            format!("label {label:?}")
        } else if let Some((program, _)) = &self.program {
            format!("program {program}")
        } else {
            "that venue".to_string()
        }
    }
}

/// What crossed the venue in one trade direction, on one side of the comparison.
#[derive(Default, Clone, Copy, Debug)]
pub struct Flow {
    /// A swap crossing the venue twice counts twice.
    pub legs: u64,
    pub usd: f64,
    pub without_amount: u64,
    /// Priced at nothing rather than zero, so the dollar figure never absorbs them silently.
    pub without_price: u64,
    /// The numerator of [`Direction::share`], which is the interface to it.
    share_usd: f64,
}

impl Flow {
    fn merge(&mut self, other: Self) {
        self.legs += other.legs;
        self.usd += other.usd;
        self.without_amount += other.without_amount;
        self.without_price += other.without_price;
        self.share_usd += other.share_usd;
    }
}

/// One trade direction's before and after.
#[derive(Default, Clone, Copy, Debug)]
pub struct Direction {
    pub l1: Flow,
    pub requoted: Flow,
    /// Every venue's normalized value here — the denominator of [`Direction::share`].
    l1_all: f64,
    requoted_all: f64,
}

impl Direction {
    fn merge(&mut self, other: Self) {
        self.l1.merge(other.l1);
        self.requoted.merge(other.requoted);
        self.l1_all += other.l1_all;
        self.requoted_all += other.requoted_all;
    }

    /// The venue's percentage of all flow here, on each side. `None` when nothing could be
    /// priced, which a `0.0%` would misreport.
    pub fn share(&self) -> Option<(f64, f64)> {
        (self.l1_all > 0.0 && self.requoted_all > 0.0).then(|| {
            (
                self.l1.share_usd / self.l1_all * 100.0,
                self.requoted.share_usd / self.requoted_all * 100.0,
            )
        })
    }

    /// Whether the venue was on either side, which is what makes the direction worth a row.
    pub const fn present(&self) -> bool {
        self.l1.legs > 0 || self.requoted.legs > 0
    }

    pub const fn unpriced(&self) -> bool {
        self.l1.without_price > 0 || self.requoted.without_price > 0
    }

    /// Nothing priceable, so the dollars are dropped: a `$0` row reads as "worth nothing".
    pub fn fully_unpriced(&self) -> bool {
        self.unpriced() && self.l1.usd == 0.0 && self.requoted.usd == 0.0
    }

    /// Dollars, falling back to legs so an unpriceable book still sorts above an empty one.
    pub(super) fn rank(&self) -> (u64, u64) {
        let usd = self.l1.usd.max(self.requoted.usd);
        (usd as u64, self.l1.legs.max(self.requoted.legs))
    }
}

pub(super) fn fold(directions: impl IntoIterator<Item = Direction>) -> Direction {
    directions
        .into_iter()
        .fold(Direction::default(), |mut total, direction| {
            total.merge(direction);
            total
        })
}

/// A trade direction, keyed by the mints it moves between as `(input, output)`.
pub type Pair = (String, String);

#[derive(Clone, Copy)]
enum Side {
    L1,
    Requoted,
}

/// What a stream said about one venue.
#[derive(Debug)]
pub struct Report {
    by_direction: BTreeMap<Pair, Direction>,
    target: Target,
    /// Absent when the stream carried no SOL<->USDC reroutes to anchor from.
    sol_usd: Option<f64>,
}

impl Report {
    /// Build from anything that yields records — a mapped notification stream, a DB read.
    pub fn from_records<'a>(
        target: Target,
        records: impl IntoIterator<Item = &'a LegRecord>,
    ) -> Result<Self, RerouteReportError> {
        let mut builder = ReportBuilder::new(target);
        for record in records {
            builder.push(record);
        }
        builder.finish()
    }

    pub const fn target(&self) -> &Target {
        &self.target
    }

    pub const fn sol_usd(&self) -> Option<f64> {
        self.sol_usd
    }

    /// Every direction the range priced, which includes those the venue never served — filter
    /// on [`Direction::present`] for the venue's own.
    pub fn by_direction(&self) -> impl Iterator<Item = (&Pair, &Direction)> {
        self.by_direction.iter()
    }

    /// The directions summed. Share stays meaningful because both numerator and denominator are
    /// per-leg normalized.
    pub fn total(&self) -> Direction {
        fold(self.by_direction.values().copied())
    }
}

/// Accumulates a [`Report`] one record at a time, holding pricing samples, one accumulator per
/// trade direction, and the venue labels seen — never the records.
///
/// Every price is a median over the whole stream, so amounts accumulate raw and convert once in
/// [`ReportBuilder::finish`]. [`Prices::usd`] is linear in the amount, which is what makes that
/// identical to converting each hop as it arrives.
pub struct ReportBuilder {
    target: Target,
    samples: Samples,
    by_direction: Directions,
    /// Venue labels the quotes named, for the error a selector that matches nothing raises.
    labels: BTreeMap<String, u64>,
}

impl ReportBuilder {
    pub fn new(target: Target) -> Self {
        Self {
            target,
            samples: Samples::default(),
            by_direction: Directions::default(),
            labels: BTreeMap::new(),
        }
    }

    /// Take one record's contribution. Cheap and order-independent.
    pub fn push(&mut self, record: &LegRecord) {
        self.samples.push(record);

        // Neither column counts flow that never landed, so the two are filtered alike.
        if record.failed || record.original_failed {
            return;
        }
        let Self {
            target,
            by_direction,
            labels,
            ..
        } = self;
        fn hops_of(plan: &Option<RoutePlan>) -> Option<&[RouteHop]> {
            plan.as_ref().map(RoutePlan::hops)
        }
        // Used twice: the census below, and the fallback when there is no fill plan.
        let quoted = hops_of(&record.route_plan);
        for label in quoted.iter().copied().flatten().filter_map(RouteHop::label) {
            match labels.get_mut(label) {
                Some(hops) => *hops += 1,
                None => {
                    labels.insert(label.to_string(), 1);
                }
            }
        }

        // The fill, so both columns compare a fill against a fill; the quote is the fallback.
        let (requoted, from_quote) = match hops_of(&record.realized_route_plan) {
            Some(filled) => (filled, false),
            None => (quoted.unwrap_or_default(), true),
        };
        let claimed = |hop: &RouteHop| match from_quote {
            true => target.claims_quoted(hop),
            false => target.claims_fill(hop),
        };
        for hop in requoted.iter().filter(|hop| claimed(hop)) {
            by_direction.record(Side::Requoted, hop);
        }

        let l1 = hops_of(&record.original_route_plan);
        for hop in l1
            .iter()
            .copied()
            .flatten()
            .filter(|hop| target.claims_fill(hop))
        {
            by_direction.record(Side::L1, hop);
        }

        // The leg's own value, counted once whichever routes it took, so the shares are over
        // the population rather than over the hops the venue served.
        let leg_amount = u128::from(record.amount) as f64;
        by_direction.accumulate_share(
            Side::Requoted,
            requoted,
            record.input_mint,
            leg_amount,
            claimed,
        );
        if let Some(l1) = l1 {
            by_direction.accumulate_share(Side::L1, l1, record.input_mint, leg_amount, |hop| {
                target.claims_fill(hop)
            });
        }
    }

    /// Nothing matched on either side means the selector named something the stream never saw.
    pub fn finish(self) -> Result<Report, RerouteReportError> {
        let prices = self.samples.prices();
        let report = Report {
            sol_usd: prices.as_ref().map(Prices::sol_usd),
            by_direction: self.by_direction.price(prices.as_ref()),
            target: self.target,
        };
        let total = report.total();
        if total.l1.legs == 0 && total.requoted.legs == 0 {
            return Err(RerouteReportError::NothingMatched {
                asked: report.target.describe(),
                venues: self.labels.into_iter().collect(),
            });
        }
        Ok(report)
    }
}

/// In its own type so `record` and `accumulate_share` borrow only the map, leaving the rest of
/// the builder free.
#[derive(Default)]
struct Directions(BTreeMap<Pair, DirectionAccum>);

impl Directions {
    /// The hop's notional. Its input mint is the direction's, so raw amounts sum unpriced.
    fn record(&mut self, side: Side, hop: &RouteHop) {
        let Some(key) = key_of(hop) else {
            return;
        };
        let flow = &mut self.0.entry(key).or_default().side_mut(side).flow;
        flow.legs += 1;
        match in_amount(hop) {
            Some(amount) => flow.raw += amount,
            None => flow.without_amount += 1,
        }
    }

    /// A leg's value split across its route's venues, filed under each hop's own direction, so
    /// every leg counts once and the shares over a direction sum to 100%.
    ///
    /// Credited in the *leg's* input mint, which is not the direction's on a multi-hop route —
    /// hence a bucket per mint.
    fn accumulate_share(
        &mut self,
        side: Side,
        hops: &[RouteHop],
        leg_mint: Address,
        leg_amount: f64,
        claimed: impl Fn(&RouteHop) -> bool,
    ) {
        let total: u64 = hops.iter().map(|hop| hop.percent).sum();
        if total == 0 {
            return;
        }
        for hop in hops {
            let Some(key) = key_of(hop) else {
                continue;
            };
            let value = leg_amount * hop.percent as f64 / total as f64;
            let share = &mut self.0.entry(key).or_default().side_mut(side).share;
            credit(&mut share.all, leg_mint, value);
            if claimed(hop) {
                credit(&mut share.claimed, leg_mint, value);
            }
        }
    }

    /// A direction with nothing priceable and no venue legs carries no measurement — its bucket
    /// was opened before its mint was known to be unpriceable — so it is dropped, not zeroed.
    fn price(self, prices: Option<&Prices>) -> BTreeMap<Pair, Direction> {
        self.0
            .into_iter()
            .map(|(pair, accum)| {
                let direction = accum.price(&pair.0, prices);
                (pair, direction)
            })
            .filter(|(_, direction)| {
                direction.present() || direction.l1_all > 0.0 || direction.requoted_all > 0.0
            })
            .collect()
    }
}

/// `None` for a hop whose pair the plan never named: keying it on a default address would pool
/// unrelated unnamed trades into one priced bucket, so such a hop opens no direction at all.
fn key_of(hop: &RouteHop) -> Option<Pair> {
    Some((
        hop.input_mint()?.to_string(),
        hop.output_mint()?.to_string(),
    ))
}

/// Nearly every direction sees a single leg mint, so a scan beats a map; a hub pair terminating
/// routes out of many exotics is the exception.
fn credit(bucket: &mut Vec<(Address, f64)>, mint: Address, value: f64) {
    match bucket.iter_mut().find(|(held, _)| *held == mint) {
        Some((_, total)) => *total += value,
        None => bucket.push((mint, value)),
    }
}

/// Raw amounts for one side of one direction, awaiting a price.
#[derive(Default)]
struct FlowAccum {
    legs: u64,
    /// In the direction's input mint, shared by every hop filed here.
    raw: u128,
    without_amount: u64,
}

impl FlowAccum {
    fn price(self, mint: &str, prices: Option<&Prices>, share_usd: f64) -> Flow {
        let usd = prices.and_then(|prices| prices.usd_str(mint, self.raw as f64));
        Flow {
            legs: self.legs,
            usd: usd.unwrap_or_default(),
            without_amount: self.without_amount,
            // Every hop here shares one mint, so the range prices all of them or none.
            without_price: match usd {
                Some(_) => 0,
                None => self.legs - self.without_amount,
            },
            share_usd,
        }
    }
}

/// Weighted leg value for one side of one direction, per the leg's own input mint.
#[derive(Default)]
struct ShareAccum {
    all: Vec<(Address, f64)>,
    claimed: Vec<(Address, f64)>,
}

impl ShareAccum {
    /// `(all, claimed)`. An unpriceable mint contributes to neither, keeping the ratio honest.
    fn price(&self, prices: Option<&Prices>) -> (f64, f64) {
        let sum = |bucket: &[(Address, f64)]| {
            bucket
                .iter()
                .filter_map(|(mint, raw)| prices?.usd(mint, *raw))
                // Not `sum`: `Sum` for floats starts at `-0.0`, so an empty bucket would
                // render as `-0.0%`.
                .fold(0.0, |total, usd| total + usd)
        };
        (sum(&self.all), sum(&self.claimed))
    }
}

/// Paired so a hop's notional and its share cannot be filed against different sides.
#[derive(Default)]
struct SideAccum {
    flow: FlowAccum,
    share: ShareAccum,
}

#[derive(Default)]
struct DirectionAccum {
    l1: SideAccum,
    requoted: SideAccum,
}

impl DirectionAccum {
    fn side_mut(&mut self, side: Side) -> &mut SideAccum {
        match side {
            Side::L1 => &mut self.l1,
            Side::Requoted => &mut self.requoted,
        }
    }

    fn price(self, mint: &str, prices: Option<&Prices>) -> Direction {
        let (l1_all, l1_claimed) = self.l1.share.price(prices);
        let (requoted_all, requoted_claimed) = self.requoted.share.price(prices);
        Direction {
            l1: self.l1.flow.price(mint, prices, l1_claimed),
            requoted: self.requoted.flow.price(mint, prices, requoted_claimed),
            l1_all,
            requoted_all,
        }
    }
}

#[cfg(test)]
mod tests {
    use super::*;
    use crate::{
        mints,
        reroute_report::testing::{hop, plan, record_of},
    };

    const SOL: &str = "So11111111111111111111111111111111111111112";
    const USDC: &str = "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v";
    const VENUE_PROGRAM: &str = "BiSoNHVpsVZW2F7rx2eQ59yQwKxzU5NvBcmKshCSUypi";
    const OTHER_PROGRAM: &str = "whirLbMiicVdio4qvUfM5KAg6Ct8VwpYzGff3uctyCc";

    /// Fixes SOL at $100 from the stream's own swaps. Carries no route plan, so it prices the
    /// range without contributing a hop to anything.
    fn anchors() -> Vec<LegRecord> {
        (1..=3)
            .map(|n| LegRecord {
                original_realized_output_amount: Some(n * 100_000_000),
                ..record_of(mints::SOL, mints::USDC, n * 1_000_000_000, None, None, None)
            })
            .collect()
    }

    fn venue() -> Target {
        Target::new(
            Some("BisonFi".to_string()),
            Some(VENUE_PROGRAM.parse().expect("a venue program")),
        )
    }

    fn fill(
        program: &str,
        label: &str,
        input: &str,
        output: &str,
        amount: u64,
    ) -> Option<RoutePlan> {
        plan(vec![hop(Some(program), label, input, output, amount)])
    }

    fn report_of(records: &[LegRecord]) -> Report {
        Report::from_records(venue(), records).expect("the venue appears")
    }

    /// The anchors, plus whatever the test is actually about.
    fn priced(extra: impl IntoIterator<Item = LegRecord>) -> Vec<LegRecord> {
        let mut records = anchors();
        records.extend(extra);
        records
    }

    /// A leg the venue won: the re-quote routed it through the venue, L1 had it elsewhere.
    fn won_leg(amount: u64) -> LegRecord {
        let realized = fill(VENUE_PROGRAM, "BisonFi", SOL, USDC, amount);
        let l1 = fill(OTHER_PROGRAM, "Whirlpool", SOL, USDC, amount);
        record_of(mints::SOL, mints::USDC, amount, None, l1, realized)
    }

    /// A hop whose pair the plan never named opens no direction: keyed on a default address it
    /// would pool unrelated unnamed trades into one priced bucket. Its named sibling still
    /// counts alone.
    #[test]
    fn a_hop_with_an_unnamed_mint_opens_no_direction() {
        let mut unnamed = hop(Some(VENUE_PROGRAM), "BisonFi", USDC, SOL, 1_000_000);
        unnamed.swap_info.output_mint = None;
        let l1 = plan(vec![
            hop(Some(VENUE_PROGRAM), "BisonFi", SOL, USDC, 2_000_000_000),
            unnamed,
        ]);
        let report = report_of(&priced([record_of(
            mints::SOL,
            mints::USDC,
            2_000_000_000,
            None,
            l1,
            None,
        )]));

        let pairs: Vec<&Pair> = report.by_direction().map(|(pair, _)| pair).collect();
        assert_eq!(pairs, [&(SOL.to_string(), USDC.to_string())]);
        assert_eq!(report.total().l1.legs, 1, "only the named hop counts");
    }

    /// Prices are medians over the whole stream, so no dollar figure exists until it ends. The
    /// builder holds raw amounts and converts once — which only works because the conversion is
    /// linear, and this is the test of that.
    #[test]
    fn deferring_the_conversion_matches_pricing_each_hop_as_it_arrives() {
        let report = report_of(&priced([won_leg(2_000_000_000), won_leg(3_000_000_000)]));
        let total = report.total();

        assert_eq!(report.sol_usd(), Some(100.0));
        assert_eq!(total.requoted.legs, 2);
        // 2 SOL and 3 SOL at $100, whether summed raw and converted once or converted twice.
        assert_eq!(total.requoted.usd, 500.0);
        assert_eq!(total.l1.legs, 0, "L1 had these legs at another venue");
    }

    /// The order records arrive in is the order the session produced them, which is not a
    /// property of the venue. Every figure must be a fold, not a sequence.
    #[test]
    fn the_result_does_not_depend_on_arrival_order() {
        let forward = priced([won_leg(2_000_000_000), won_leg(3_000_000_000)]);
        let mut backward = forward.clone();
        backward.reverse();

        let (forward, backward) = (report_of(&forward), report_of(&backward));
        assert_eq!(forward.sol_usd(), backward.sol_usd());
        assert_eq!(forward.total().requoted.usd, backward.total().requoted.usd);
        assert_eq!(forward.render(None), backward.render(None));
    }

    /// Neither column counts flow that never landed, and the two must be filtered alike — a
    /// reverted simulation is not a leg the venue won, and a failed original is not one it held.
    #[test]
    fn neither_side_counts_flow_that_never_landed() {
        let records = priced([
            won_leg(2_000_000_000),
            LegRecord {
                failed: true,
                ..won_leg(9_000_000_000)
            },
            LegRecord {
                original_failed: true,
                ..won_leg(9_000_000_000)
            },
        ]);

        let total = report_of(&records).total();
        assert_eq!(total.requoted.legs, 1, "only the landed leg counts");
        assert_eq!(total.requoted.usd, 200.0);
    }

    /// Volume share needs every leg counted once, so a two-hop route gives each half — where
    /// per-hop notional credits both in full. The two answer different questions.
    #[test]
    fn a_share_splits_a_leg_where_notional_counts_it_twice() {
        let two_hops = plan(vec![
            hop(Some(VENUE_PROGRAM), "BisonFi", SOL, USDC, 1_000_000_000),
            hop(Some(OTHER_PROGRAM), "Whirlpool", USDC, "BONK", 100_000_000),
        ]);
        let l1 = fill(VENUE_PROGRAM, "BisonFi", SOL, USDC, 1_000_000_000);
        let record = record_of(mints::SOL, mints::USDC, 1_000_000_000, None, l1, two_hops);
        let report = report_of(&priced([record]));

        let total = report.total();
        // The leg is one SOL, $100. Per-hop notional credits the venue the whole of its own hop.
        assert_eq!(total.requoted.usd, 100.0);
        // Share splits that $100 across the two hops on the route, and the venue holds one.
        assert_eq!(total.requoted_all, 100.0, "the leg is counted once");
        assert_eq!(
            total.requoted.share_usd, 50.0,
            "half the route was the venue's"
        );
        // On L1 it held the leg outright.
        assert_eq!(total.share(), Some((100.0, 50.0)));

        // Each hop is filed under its own direction, so the rows decompose the same measure.
        let (_, first) = report
            .by_direction()
            .find(|((input, output), _)| input == SOL && output == USDC)
            .expect("the venue's direction");
        assert_eq!(first.requoted.share_usd, 50.0);
        assert_eq!(first.requoted_all, 50.0, "that direction held half the leg");
    }

    /// The program wins when given; the label is the fallback, so naming only a label still
    /// measures the fill columns rather than reporting a silent zero on them.
    #[test]
    fn a_fill_prefers_the_program_and_falls_back_to_the_label() {
        let filled = fill(VENUE_PROGRAM, "BisonFi", SOL, USDC, 1_000);
        let record = record_of(mints::SOL, mints::USDC, 1_000, None, filled.clone(), filled);
        let hop = &record.original_route_plan.as_ref().expect("a plan").hops()[0];

        let by_label = Target::new(Some("BisonFi".to_string()), None);
        assert!(by_label.claims_fill(hop));
        assert!(by_label.claims_quoted(hop));

        // A program that was given and does not match is not rescued by a matching label.
        let other = Target::new(Some("BisonFi".to_string()), Some(Address::new_unique()));
        assert!(!other.claims_fill(hop));

        let by_program = Target::new(None, Some(VENUE_PROGRAM.parse().expect("a program")));
        assert!(by_program.claims_fill(hop));
        // The quote names no program, so this key cannot match there.
        assert!(!by_program.claims_quoted(hop));
    }

    /// Dollars cross mints; a raw amount does not. Summing each direction's own input mint added
    /// lamports to stablecoin units and produced a figure that looked precise and meant nothing,
    /// so no amount is reported in mint units anywhere — only legs and dollars.
    #[test]
    fn the_report_is_swaps_and_dollars_only() {
        let sell = fill(VENUE_PROGRAM, "BisonFi", SOL, USDC, 1_000_000_000);
        let buy = fill(VENUE_PROGRAM, "BisonFi", USDC, SOL, 100_000_000);
        let report = report_of(&priced([
            record_of(mints::SOL, mints::USDC, 1_000_000_000, None, None, sell),
            record_of(mints::USDC, mints::SOL, 100_000_000, None, None, buy),
        ]));

        // Lamports in one direction, stablecoin units in the other; dollars survive the sum.
        let json = report.to_json();
        assert_eq!(json["total"]["l1"]["swaps"], 0);
        assert_eq!(json["total"]["requoted"]["swaps"], 2);
        assert_eq!(json["total"]["requoted"]["usd"], 200.0);

        // And the rendered table carries the two rows, and no third.
        let table = report.render(None);
        let totals = table.split('→').next().expect("a totals block");
        assert!(totals.contains("swaps") && totals.contains("volume"));
        assert!(!totals.contains("raw in"), "a raw amount reached the table");
        // "re-quoted" is a column heading; a *quoted fill* line is what must not appear.
        assert!(!table.contains("quoted fill"));
    }

    /// A range with nothing to anchor on prices nothing. Reporting those legs at $0 would read
    /// as "worth nothing" rather than "not valued".
    #[test]
    fn a_range_that_cannot_be_priced_reports_no_dollars() {
        let report = report_of(&[won_leg(2_000_000_000)]);
        let total = report.total();

        assert_eq!(report.sol_usd(), None);
        assert_eq!(total.requoted.legs, 1);
        assert_eq!(total.requoted.without_price, 1);
        assert!(total.fully_unpriced());

        let table = report.render(None);
        assert!(!table.contains("volume"), "a dollar row without a price");
        assert!(table.contains("could not price"));
    }

    /// A selector that matches nothing is a wrong address or a misspelling, not a venue with no
    /// flow. Reporting it as $0 was indistinguishable from the real thing.
    #[test]
    fn a_selector_that_matches_nothing_says_so() {
        let quote = plan(vec![hop(None, "Whirlpool", SOL, USDC, 1_000)]);
        let records = vec![record_of(mints::SOL, mints::USDC, 1_000, quote, None, None)];

        let target = Target::new(Some("Nope".to_string()), None);
        let error = Report::from_records(target, &records).expect_err("the venue never appears");

        let message = error.to_string();
        assert!(message.contains("Nope"), "names what was asked for");
        // And what the stream does name, so the misspelling is visible.
        assert!(message.contains("Whirlpool (1)"));
    }

    /// The subtitle is the caller's, since this module cannot know a slot range.
    #[test]
    fn the_subtitle_is_the_callers() {
        let report = report_of(&[won_leg(2_000_000_000)]);
        assert!(report.render(Some("slots 1–100")).contains("slots 1–100"));
        assert!(!report.render(None).contains("slots"));
    }
}