Files
wz-phone/crates/wzp-proto/src/quality.rs

853 lines
30 KiB
Rust

//! See also: [`crate::dred_tuner`] for continuous DRED tuning within a tier.
use std::collections::VecDeque;
use std::sync::Arc;
use std::time::{Duration, Instant};
use crate::BandwidthEstimator;
use crate::QualityProfile;
use crate::packet::QualityReport;
use crate::traits::QualityController;
/// Network quality tier — drives codec and FEC selection.
///
/// 5-tier range from studio quality down to catastrophic:
/// Studio64k > Studio48k > Studio32k > Good > Degraded > Catastrophic
#[derive(Clone, Copy, Debug, PartialEq, Eq, PartialOrd, Ord)]
pub enum Tier {
/// loss >= 15% OR RTT >= 200ms — Codec2 1.2k
Catastrophic = 0,
/// loss < 15% AND RTT < 200ms — Opus 6k
Degraded = 1,
/// loss < 5% AND RTT < 100ms — Opus 24k
Good = 2,
/// loss < 2% AND RTT < 80ms — Opus 32k
Studio32k = 3,
/// loss < 1% AND RTT < 50ms — Opus 48k
Studio48k = 4,
/// loss < 1% AND RTT < 30ms — Opus 64k
Studio64k = 5,
}
impl Tier {
pub fn profile(self) -> QualityProfile {
match self {
Self::Studio64k => QualityProfile::STUDIO_64K,
Self::Studio48k => QualityProfile::STUDIO_48K,
Self::Studio32k => QualityProfile::STUDIO_32K,
Self::Good => QualityProfile::GOOD,
Self::Degraded => QualityProfile::DEGRADED,
Self::Catastrophic => QualityProfile::CATASTROPHIC,
}
}
/// Determine which tier a quality report belongs to (default/WiFi thresholds).
pub fn classify(report: &QualityReport) -> Self {
Self::classify_with_context(report, NetworkContext::Unknown)
}
/// Classify with network-context-aware thresholds.
pub fn classify_with_context(report: &QualityReport, context: NetworkContext) -> Self {
let loss = report.loss_percent();
let rtt = report.rtt_ms();
match context {
NetworkContext::CellularLte
| NetworkContext::Cellular5g
| NetworkContext::Cellular3g => {
// Tighter thresholds for cellular — no studio tiers
if loss > 25.0 || rtt > 500 {
Self::Catastrophic
} else if loss > 8.0 || rtt > 300 {
Self::Degraded
} else {
Self::Good
}
}
NetworkContext::WiFi | NetworkContext::Unknown => {
if loss >= 15.0 || rtt >= 200 {
Self::Catastrophic
} else if loss >= 5.0 || rtt >= 100 {
Self::Degraded
} else if loss >= 2.0 || rtt >= 80 {
Self::Good
} else if loss >= 1.0 || rtt >= 50 {
Self::Studio32k
} else if rtt >= 30 {
Self::Studio48k
} else {
Self::Studio64k
}
}
}
}
/// Return the next lower (worse) tier, or None if already at the worst.
pub fn downgrade(self) -> Option<Tier> {
match self {
Self::Studio64k => Some(Self::Studio48k),
Self::Studio48k => Some(Self::Studio32k),
Self::Studio32k => Some(Self::Good),
Self::Good => Some(Self::Degraded),
Self::Degraded => Some(Self::Catastrophic),
Self::Catastrophic => None,
}
}
/// Whether this is a studio tier (above Good).
pub fn is_studio(self) -> bool {
matches!(self, Self::Studio64k | Self::Studio48k | Self::Studio32k)
}
}
/// Describes the network transport type for context-aware quality decisions.
#[derive(Clone, Copy, Debug, Default, PartialEq, Eq)]
pub enum NetworkContext {
WiFi,
CellularLte,
Cellular5g,
Cellular3g,
#[default]
Unknown,
}
/// Adaptive quality controller with hysteresis to prevent tier flapping.
///
/// - Downgrade: 3 consecutive reports in a worse tier (2 on cellular)
/// - Upgrade: 10 consecutive reports in a better tier
pub struct AdaptiveQualityController {
current_tier: Tier,
current_profile: QualityProfile,
/// Count of consecutive reports suggesting a higher (better) tier.
consecutive_up: u32,
/// Count of consecutive reports suggesting a lower (worse) tier.
consecutive_down: u32,
/// Sliding window of recent reports for smoothing.
history: VecDeque<QualityReport>,
/// Whether the profile was manually forced (disables adaptive logic).
forced: bool,
/// Current network context for threshold selection.
network_context: NetworkContext,
/// FEC boost expiry time (set during network handoff).
fec_boost_until: Option<Instant>,
/// FEC boost amount to add during handoff recovery window.
fec_boost_amount: f32,
/// Probing state: when Some, we're actively testing a higher tier.
probe: Option<ProbeState>,
/// Time spent stable at the current tier (for probe trigger).
stable_since: Option<Instant>,
/// Optional bandwidth estimator for BWE-guarded upgrades.
bwe: Option<Arc<BandwidthEstimator>>,
}
/// Threshold for downgrading (fast reaction to degradation).
const DOWNGRADE_THRESHOLD: u32 = 3;
/// Threshold for downgrading on cellular networks (even faster).
const CELLULAR_DOWNGRADE_THRESHOLD: u32 = 2;
/// Threshold for upgrading from Catastrophic/Degraded to Good.
const UPGRADE_THRESHOLD: u32 = 5;
/// Threshold for upgrading into studio tiers (very conservative).
const STUDIO_UPGRADE_THRESHOLD: u32 = 10;
/// Maximum history window size.
const HISTORY_SIZE: usize = 20;
/// Default FEC boost amount during handoff recovery.
const DEFAULT_FEC_BOOST: f32 = 0.2;
/// Duration of FEC boost after a network handoff.
const FEC_BOOST_DURATION_SECS: u64 = 10;
/// Minimum time stable at current tier before probing upward (30 seconds).
const PROBE_STABLE_SECS: u64 = 30;
/// Duration of a probe window (5 seconds — ~25 quality reports at 1/s).
const PROBE_DURATION_SECS: u64 = 5;
/// Maximum bad reports during probe before aborting (1 out of ~5 = 20%).
const PROBE_MAX_BAD: u32 = 1;
/// Cooldown after a failed probe before trying again (60 seconds).
const PROBE_COOLDOWN_SECS: u64 = 60;
/// Active bandwidth probe state.
struct ProbeState {
/// The tier we're probing (one step above current).
target_tier: Tier,
/// Profile to apply during probe.
target_profile: QualityProfile,
/// When the probe started.
started: Instant,
/// Reports observed during probe.
probe_reports: u32,
/// Bad reports during probe (loss/RTT exceeded target tier thresholds).
bad_reports: u32,
}
impl AdaptiveQualityController {
pub fn new() -> Self {
Self {
current_tier: Tier::Good,
current_profile: QualityProfile::GOOD,
consecutive_up: 0,
consecutive_down: 0,
history: VecDeque::with_capacity(HISTORY_SIZE),
forced: false,
network_context: NetworkContext::default(),
fec_boost_until: None,
fec_boost_amount: DEFAULT_FEC_BOOST,
probe: None,
stable_since: None,
bwe: None,
}
}
/// Get the current tier.
pub fn tier(&self) -> Tier {
self.current_tier
}
/// Get the current network context.
pub fn network_context(&self) -> NetworkContext {
self.network_context
}
/// Signal a network transport change (e.g., WiFi to cellular handoff).
///
/// When switching from WiFi to any cellular type, this preemptively
/// downgrades one quality tier and activates a temporary FEC boost.
pub fn signal_network_change(&mut self, new_context: NetworkContext) {
let old = self.network_context;
self.network_context = new_context;
let new_is_cellular = matches!(
new_context,
NetworkContext::CellularLte | NetworkContext::Cellular5g | NetworkContext::Cellular3g
);
// If switching from WiFi to cellular, preemptively downgrade one tier
if old == NetworkContext::WiFi && new_is_cellular {
if let Some(lower_tier) = self.current_tier.downgrade() {
self.current_tier = lower_tier;
self.current_profile = lower_tier.profile();
}
// Reset counters to avoid stale hysteresis state
self.consecutive_up = 0;
self.consecutive_down = 0;
// Un-force so adaptive logic resumes
self.forced = false;
}
// Cancel any active probe
self.probe = None;
self.stable_since = None;
// Activate FEC boost for any network change
self.fec_boost_until = Some(Instant::now() + Duration::from_secs(FEC_BOOST_DURATION_SECS));
}
/// Returns the FEC boost amount if within the handoff recovery window, 0.0 otherwise.
///
/// Callers should add this to their base FEC ratio during the boost window.
pub fn fec_boost(&self) -> f32 {
if let Some(until) = self.fec_boost_until {
if Instant::now() < until {
return self.fec_boost_amount;
}
}
0.0
}
/// Reset the hysteresis counters.
pub fn reset_counters(&mut self) {
self.consecutive_up = 0;
self.consecutive_down = 0;
self.probe = None;
self.stable_since = None;
}
/// Attach a bandwidth estimator for BWE-guarded tier transitions.
pub fn set_bandwidth_estimator(&mut self, bwe: Arc<BandwidthEstimator>) {
self.bwe = Some(bwe);
}
/// Return the bitrate ceiling (in bps) for a given tier, including FEC overhead.
fn tier_ceiling_bps(tier: Tier) -> u64 {
let kbps = tier.profile().total_bitrate_kbps();
(kbps * 1000.0) as u64
}
/// Get the effective downgrade threshold based on network context.
fn downgrade_threshold(&self) -> u32 {
match self.network_context {
NetworkContext::CellularLte
| NetworkContext::Cellular5g
| NetworkContext::Cellular3g => CELLULAR_DOWNGRADE_THRESHOLD,
_ => DOWNGRADE_THRESHOLD,
}
}
fn try_transition(&mut self, observed_tier: Tier) -> Option<QualityProfile> {
if observed_tier == self.current_tier {
self.consecutive_up = 0;
self.consecutive_down = 0;
return None;
}
let is_worse = observed_tier < self.current_tier;
if is_worse {
self.consecutive_up = 0;
self.consecutive_down += 1;
if self.consecutive_down >= self.downgrade_threshold() {
// Jump directly to the observed tier (don't step one-at-a-time on downgrade)
self.current_tier = observed_tier;
self.current_profile = observed_tier.profile();
self.consecutive_down = 0;
return Some(self.current_profile);
}
} else {
// Better conditions
self.consecutive_down = 0;
self.consecutive_up += 1;
// Studio tiers require more consecutive good reports
let threshold = if self.current_tier >= Tier::Good {
STUDIO_UPGRADE_THRESHOLD
} else {
UPGRADE_THRESHOLD
};
if self.consecutive_up >= threshold {
// Only upgrade one step at a time
if let Some(next_tier) = self.upgrade_one_step() {
// BWE guard: require 130% headroom over target tier bitrate
if let Some(ref bwe) = self.bwe {
let required = (Self::tier_ceiling_bps(next_tier) * 130) / 100;
if bwe.target_send_bps() < required {
// Insufficient bandwidth — reset counter to prevent flapping
self.consecutive_up = 0;
return None;
}
}
self.current_tier = next_tier;
self.current_profile = next_tier.profile();
self.consecutive_up = 0;
return Some(self.current_profile);
}
}
}
None
}
/// Check whether to start, continue, or conclude a bandwidth probe.
///
/// Called from `observe()` when no hysteresis transition fired.
fn check_probe(&mut self, observed_tier: Tier) -> Option<QualityProfile> {
// Don't probe if forced, or if already at highest tier, or on cellular
if self.forced || self.current_tier == Tier::Studio64k {
return None;
}
if matches!(
self.network_context,
NetworkContext::CellularLte | NetworkContext::Cellular5g | NetworkContext::Cellular3g
) {
return None;
}
// If we have an active probe, evaluate it
if let Some(ref mut probe) = self.probe {
probe.probe_reports += 1;
// Check if the observed tier meets the probe target
if observed_tier < probe.target_tier {
probe.bad_reports += 1;
}
// Probe failed: too many bad reports
if probe.bad_reports > PROBE_MAX_BAD {
let _failed_probe = self.probe.take();
// Reset stable_since to trigger cooldown
self.stable_since = Some(Instant::now() + Duration::from_secs(PROBE_COOLDOWN_SECS));
return None; // stay at current tier
}
// Probe succeeded: enough good reports within the window
if probe.started.elapsed() >= Duration::from_secs(PROBE_DURATION_SECS) {
let target = probe.target_tier;
let profile = probe.target_profile;
self.probe.take();
self.current_tier = target;
self.current_profile = profile;
self.consecutive_up = 0;
self.stable_since = Some(Instant::now());
return Some(profile);
}
return None; // probe still running
}
// No active probe — check if we should start one
if observed_tier >= self.current_tier {
// Track stability
if self.stable_since.is_none() {
self.stable_since = Some(Instant::now());
}
if let Some(stable_since) = self.stable_since {
if stable_since.elapsed() >= Duration::from_secs(PROBE_STABLE_SECS) {
// Stable long enough — start probing
if let Some(next) = self.upgrade_one_step() {
self.probe = Some(ProbeState {
target_tier: next,
target_profile: next.profile(),
started: Instant::now(),
probe_reports: 0,
bad_reports: 0,
});
// Return the probe profile so the encoder switches
return Some(next.profile());
}
}
}
} else {
// Conditions degraded — reset stability timer
self.stable_since = None;
}
None
}
fn upgrade_one_step(&self) -> Option<Tier> {
match self.current_tier {
Tier::Catastrophic => Some(Tier::Degraded),
Tier::Degraded => Some(Tier::Good),
Tier::Good => Some(Tier::Studio32k),
Tier::Studio32k => Some(Tier::Studio48k),
Tier::Studio48k => Some(Tier::Studio64k),
Tier::Studio64k => None,
}
}
}
impl Default for AdaptiveQualityController {
fn default() -> Self {
Self::new()
}
}
impl QualityController for AdaptiveQualityController {
fn observe(&mut self, report: &QualityReport) -> Option<QualityProfile> {
// Store in history
if self.history.len() >= HISTORY_SIZE {
self.history.pop_front();
}
self.history.push_back(*report);
if self.forced {
return None;
}
let observed = Tier::classify_with_context(report, self.network_context);
// First check for downgrades/upgrades via hysteresis
if let Some(profile) = self.try_transition(observed) {
// Cancel any active probe on tier change
self.probe.take();
self.stable_since = None;
return Some(profile);
}
// Then check probing
self.check_probe(observed)
}
fn force_profile(&mut self, profile: QualityProfile) {
self.current_profile = profile;
self.forced = true;
self.consecutive_up = 0;
self.consecutive_down = 0;
}
fn current_profile(&self) -> QualityProfile {
self.current_profile
}
}
#[cfg(test)]
mod tests {
use super::*;
fn make_report(loss_pct_f: f32, rtt_ms: u16) -> QualityReport {
QualityReport {
loss_pct: (loss_pct_f / 100.0 * 255.0) as u8,
rtt_4ms: (rtt_ms / 4) as u8,
jitter_ms: 10,
bitrate_cap_kbps: 200,
}
}
#[test]
fn starts_at_good() {
let ctrl = AdaptiveQualityController::new();
assert_eq!(ctrl.tier(), Tier::Good);
assert_eq!(ctrl.current_profile().codec, crate::CodecId::Opus24k);
}
#[test]
fn downgrades_after_threshold() {
let mut ctrl = AdaptiveQualityController::new();
// 2 bad reports — not enough
let bad = make_report(50.0, 300);
assert!(ctrl.observe(&bad).is_none());
assert!(ctrl.observe(&bad).is_none());
assert_eq!(ctrl.tier(), Tier::Good);
// 3rd bad report triggers downgrade
let result = ctrl.observe(&bad);
assert!(result.is_some());
assert_eq!(ctrl.tier(), Tier::Catastrophic);
}
#[test]
fn upgrades_slowly() {
let mut ctrl = AdaptiveQualityController::new();
// Force to catastrophic
let bad = make_report(50.0, 300);
for _ in 0..3 {
ctrl.observe(&bad);
}
assert_eq!(ctrl.tier(), Tier::Catastrophic);
// 4 good reports — not enough (threshold is 5)
let good = make_report(0.5, 20); // studio-quality report
for _ in 0..4 {
assert!(ctrl.observe(&good).is_none());
}
assert_eq!(ctrl.tier(), Tier::Catastrophic);
// 5th good report triggers upgrade (one step: Catastrophic → Degraded)
let result = ctrl.observe(&good);
assert!(result.is_some());
assert_eq!(ctrl.tier(), Tier::Degraded);
// Another 5 to go from Degraded → Good
for _ in 0..4 {
assert!(ctrl.observe(&good).is_none());
}
let result = ctrl.observe(&good);
assert!(result.is_some());
assert_eq!(ctrl.tier(), Tier::Good);
// Studio upgrades need 10 consecutive — Good → Studio32k
for _ in 0..9 {
assert!(ctrl.observe(&good).is_none());
}
let result = ctrl.observe(&good);
assert!(result.is_some());
assert_eq!(ctrl.tier(), Tier::Studio32k);
}
#[test]
fn forced_profile_disables_adaptive() {
let mut ctrl = AdaptiveQualityController::new();
ctrl.force_profile(QualityProfile::CATASTROPHIC);
// Bad reports don't trigger transitions when forced
let bad = make_report(50.0, 300);
for _ in 0..10 {
assert!(ctrl.observe(&bad).is_none());
}
}
#[test]
fn bwe_guard_blocks_upgrade_when_bandwidth_insufficient() {
let mut ctrl = AdaptiveQualityController::new();
// Force to catastrophic
let bad = make_report(50.0, 300);
for _ in 0..3 {
ctrl.observe(&bad);
}
assert_eq!(ctrl.tier(), Tier::Catastrophic);
// Attach a BWE with very low headroom.
// Degraded tier needs 6kbps * 1.5 FEC = 9kbps → 130% = 11.7kbps.
// Set target_send_bps ≈ 9_000 (below 11_700 threshold).
let bwe = Arc::new(BandwidthEstimator::new(1000.0, 1.0, 100_000.0));
bwe.update_from_path(1_000_000, 0, 10); // high cwnd
bwe.update_from_peer(10_000); // low remb → target = 9_000
ctrl.set_bandwidth_estimator(bwe.clone());
let good = make_report(0.5, 20);
for _ in 0..5 {
assert!(
ctrl.observe(&good).is_none(),
"upgrade should be blocked by low BWE"
);
}
assert_eq!(
ctrl.tier(),
Tier::Catastrophic,
"should remain at Catastrophic"
);
// Raise BWE well above the 130% threshold
bwe.update_from_peer(100_000); // target ≈ 90_000 bps
// Counter was reset, need another 5 good reports
for _ in 0..4 {
assert!(ctrl.observe(&good).is_none());
}
let result = ctrl.observe(&good);
assert!(
result.is_some(),
"upgrade should proceed with sufficient BWE"
);
assert_eq!(ctrl.tier(), Tier::Degraded);
}
#[test]
fn tier_classification() {
// Studio tiers
assert_eq!(Tier::classify(&make_report(0.5, 20)), Tier::Studio64k);
assert_eq!(Tier::classify(&make_report(0.5, 40)), Tier::Studio48k);
assert_eq!(Tier::classify(&make_report(1.5, 60)), Tier::Studio32k);
// Good/Degraded/Catastrophic
assert_eq!(Tier::classify(&make_report(3.0, 90)), Tier::Good);
assert_eq!(Tier::classify(&make_report(6.0, 120)), Tier::Degraded);
assert_eq!(Tier::classify(&make_report(16.0, 120)), Tier::Catastrophic);
assert_eq!(Tier::classify(&make_report(5.0, 200)), Tier::Catastrophic);
}
#[test]
fn studio_tier_boundaries() {
// loss < 1% AND RTT < 30ms → Studio64k
assert_eq!(Tier::classify(&make_report(0.9, 28)), Tier::Studio64k);
// loss < 1% AND RTT 30-49ms → Studio48k
assert_eq!(Tier::classify(&make_report(0.9, 32)), Tier::Studio48k);
// loss < 2% AND RTT < 80ms → Studio32k (but loss >= 1%)
assert_eq!(Tier::classify(&make_report(1.5, 40)), Tier::Studio32k);
// loss >= 2% → Good (use 2.5 to survive u8 quantization)
assert_eq!(Tier::classify(&make_report(2.5, 40)), Tier::Good);
// RTT 80ms → Good
assert_eq!(Tier::classify(&make_report(0.5, 80)), Tier::Good);
}
// ---------------------------------------------------------------
// Network context tests
// ---------------------------------------------------------------
#[test]
fn cellular_tighter_thresholds() {
// 9% loss: Degraded on both WiFi (>=5%) and cellular (>=8%)
let report = make_report(9.0, 80);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::WiFi),
Tier::Degraded
);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::CellularLte),
Tier::Degraded
);
// 6% loss, low RTT: Degraded on WiFi (>=5%), Good on cellular (<8%)
let report = make_report(6.0, 80);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::WiFi),
Tier::Degraded
);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::CellularLte),
Tier::Good
);
// 30% loss: Catastrophic on WiFi (>=15%), Catastrophic on cellular (>=25%)
let report = make_report(30.0, 80);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::WiFi),
Tier::Catastrophic
);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::Cellular3g),
Tier::Catastrophic
);
}
#[test]
fn cellular_rtt_thresholds() {
// RTT 150ms: Degraded on WiFi (>=100ms), Good on cellular (<300ms and loss<8%)
let report = make_report(2.0, 148);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::WiFi),
Tier::Degraded
);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::CellularLte),
Tier::Good
);
}
#[test]
fn cellular_no_studio_tiers() {
// Even with perfect network, cellular stays at Good (no studio)
let report = make_report(0.0, 10);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::CellularLte),
Tier::Good
);
assert_eq!(
Tier::classify_with_context(&report, NetworkContext::WiFi),
Tier::Studio64k
);
}
#[test]
fn cellular_faster_downgrade() {
let mut ctrl = AdaptiveQualityController::new();
ctrl.signal_network_change(NetworkContext::CellularLte);
// Reset tier back to Good for testing downgrade threshold
ctrl.current_tier = Tier::Good;
ctrl.current_profile = Tier::Good.profile();
// On cellular, downgrade threshold is 2 instead of 3
let bad = make_report(50.0, 200);
assert!(ctrl.observe(&bad).is_none()); // 1st bad
let result = ctrl.observe(&bad); // 2nd bad — should trigger on cellular
assert!(result.is_some());
}
#[test]
fn signal_network_change_preemptive_downgrade() {
let mut ctrl = AdaptiveQualityController::new();
assert_eq!(ctrl.tier(), Tier::Good);
// Switch from WiFi to cellular
ctrl.network_context = NetworkContext::WiFi;
ctrl.signal_network_change(NetworkContext::CellularLte);
// Should have downgraded one tier: Good -> Degraded
assert_eq!(ctrl.tier(), Tier::Degraded);
}
#[test]
fn signal_network_change_fec_boost() {
let mut ctrl = AdaptiveQualityController::new();
assert_eq!(ctrl.fec_boost(), 0.0);
ctrl.signal_network_change(NetworkContext::CellularLte);
// FEC boost should be active
assert!(ctrl.fec_boost() > 0.0);
assert_eq!(ctrl.fec_boost(), DEFAULT_FEC_BOOST);
}
#[test]
fn tier_downgrade() {
assert_eq!(Tier::Studio64k.downgrade(), Some(Tier::Studio48k));
assert_eq!(Tier::Studio48k.downgrade(), Some(Tier::Studio32k));
assert_eq!(Tier::Studio32k.downgrade(), Some(Tier::Good));
assert_eq!(Tier::Good.downgrade(), Some(Tier::Degraded));
assert_eq!(Tier::Degraded.downgrade(), Some(Tier::Catastrophic));
assert_eq!(Tier::Catastrophic.downgrade(), None);
}
#[test]
fn network_context_default() {
assert_eq!(NetworkContext::default(), NetworkContext::Unknown);
}
// ---------------------------------------------------------------
// Bandwidth probing tests
// ---------------------------------------------------------------
#[test]
fn probe_triggers_after_stable_period() {
let mut ctrl = AdaptiveQualityController::new();
let excellent = make_report(0.3, 20); // would classify as Studio64k
// Starts at Good. Fast-forward stability by setting stable_since directly.
ctrl.stable_since = Some(Instant::now() - Duration::from_secs(31));
// One excellent report should trigger a probe (Good → Studio32k)
let result = ctrl.observe(&excellent);
assert!(result.is_some(), "should start probe after 30s stable");
assert!(ctrl.probe.is_some(), "probe should be active");
assert_eq!(ctrl.probe.as_ref().unwrap().target_tier, Tier::Studio32k);
}
#[test]
fn probe_succeeds_after_window() {
let mut ctrl = AdaptiveQualityController::new();
ctrl.stable_since = Some(Instant::now() - Duration::from_secs(31));
let excellent = make_report(0.3, 20);
// Trigger probe start
let result = ctrl.observe(&excellent);
assert!(result.is_some());
// Simulate probe window elapsed by backdating started
ctrl.probe.as_mut().unwrap().started =
Instant::now() - Duration::from_secs(PROBE_DURATION_SECS);
// Next good report should finalize the probe
let result = ctrl.observe(&excellent);
assert!(result.is_some(), "probe should succeed");
assert_eq!(ctrl.current_tier, Tier::Studio32k);
assert!(ctrl.probe.is_none(), "probe should be cleared");
}
#[test]
fn probe_fails_on_bad_reports() {
let mut ctrl = AdaptiveQualityController::new();
// Put controller at Studio32k, pretend we've been stable
ctrl.current_tier = Tier::Studio32k;
ctrl.current_profile = Tier::Studio32k.profile();
ctrl.stable_since = Some(Instant::now() - Duration::from_secs(31));
// Start a probe to Studio48k
let excellent = make_report(0.3, 20);
let result = ctrl.observe(&excellent);
assert!(result.is_some()); // probe started
assert_eq!(ctrl.probe.as_ref().unwrap().target_tier, Tier::Studio48k);
// Feed bad reports (loss too high for Studio48k)
let degraded = make_report(3.0, 100);
ctrl.observe(&degraded); // first bad
ctrl.observe(&degraded); // second bad — exceeds PROBE_MAX_BAD (1)
// Probe should be cancelled
assert!(
ctrl.probe.is_none(),
"probe should be cancelled after bad reports"
);
// Should still be at Studio32k (not upgraded)
assert_eq!(ctrl.current_tier, Tier::Studio32k);
}
#[test]
fn no_probe_on_cellular() {
let mut ctrl = AdaptiveQualityController::new();
ctrl.signal_network_change(NetworkContext::CellularLte);
ctrl.current_tier = Tier::Good;
ctrl.current_profile = Tier::Good.profile();
ctrl.stable_since = Some(Instant::now() - Duration::from_secs(60));
let good = make_report(0.5, 40);
let result = ctrl.observe(&good);
// Should NOT probe on cellular
assert!(ctrl.probe.is_none(), "should not probe on cellular");
assert!(result.is_none() || ctrl.current_tier == Tier::Good);
}
#[test]
fn no_probe_at_highest_tier() {
let mut ctrl = AdaptiveQualityController::new();
ctrl.current_tier = Tier::Studio64k;
ctrl.current_profile = Tier::Studio64k.profile();
ctrl.stable_since = Some(Instant::now() - Duration::from_secs(60));
let excellent = make_report(0.1, 10);
let result = ctrl.observe(&excellent);
assert!(
result.is_none(),
"should not probe when already at Studio64k"
);
}
}