constants.mjs

// studio/constants.mjs
//
// The studio's display vocabulary — the fixed taxonomy and grading scale
// the UI is built around. Pure data and pure functions only: nothing here
// touches `state` or the DOM, so it is safe to import from anywhere in the
// client (and to unit-test in isolation). The semantics are the spec's, not
// the UI's — see vendor/observability-pack-spec for the source of truth.

// The seven canonical layers. `name` is what the studio shows: the layer
// named by the artefacts on it, the wording users asked for (2026-09: the
// spec's abstract names and the "What should we measure?" questions were
// disliked). `spec` is the layer's name in the ObservabilityPack spec, kept
// for tooltips and for reading the spec side by side. Never invent layer
// semantics; the spec is the source of truth for what belongs on a layer.
export const LAYER_DEFS = [
  { id: 'L1',  num: 'L1',  name: 'SLI/SLO',                    spec: 'Contract'   },
  { id: 'L2',  num: 'L2',  name: 'Metrics/Logs/Traces',        spec: 'Telemetry'  },
  { id: 'L2X', num: 'L2X', name: 'Extended',                   spec: 'Extended'   },
  { id: 'L3',  num: 'L3',  name: 'Dashboards/Recording Rules', spec: 'Insight'    },
  { id: 'L4',  num: 'L4',  name: 'Alerts/Policy/Self-healing', spec: 'Action'     },
  { id: 'L5',  num: 'L5',  name: 'Self-check',                 spec: 'Validation' },
  { id: 'GOV', num: 'GOV', name: 'Governance',                 spec: 'Governance' },
];
// { L1: 'SLI/SLO', … } — the one map every view reads a layer's name from.
export const LAYER_NAMES = Object.fromEntries(LAYER_DEFS.map(d => [d.id, d.name]));
export const LAYER_SPEC_NAMES = Object.fromEntries(LAYER_DEFS.map(d => [d.id, d.spec]));

// NOTE: diagnostic-grade.mjs inlines its own private copy of this array so
// it can stay zero-dependency for downstream vendoring — keep the two in sync.
export const L4_SUBGROUPS = [
  { key: 'policy',   label: 'Policy' },
  { key: 'alerting', label: 'Alerting' },
  { key: 'healing',  label: 'Self-healing' },
];

// DOMAIN facet — a fixed four-bucket taxonomy that cuts ACROSS the layers,
// answering "which slice of the stack does this artefact belong to?" The
// layer (L1…GOV) says WHAT KIND of artefact it is; the domain says WHICH
// PART OF THE SYSTEM it observes. Classification is deterministic (see
// artefactDomain) and falls back to Application.
export const DOMAIN_DEFS = [
  { id: 'infrastructure', label: 'Infrastructure' },
  { id: 'platform',       label: 'Platform' },
  { id: 'application',    label: 'Application' },
  { id: 'ux',             label: 'User Experience' },
];

// Slab accents only — the layer NAMES come from LAYER_DEFS above. Never
// invent layer semantics; the spec is the source of truth.
export const DISCO_SLAB_ACCENT = {
  L1: '#3b82f6', L2: '#06b6d4', L2X: '#0ea5e9', L3: '#10b981',
  L4: '#f59e0b', L5: '#a855f7', GOV: '#64748b',
};

// Conformance-percentage → letter grade / one-word verdict. The scale is
// the conventional US academic banding; both are pure of any UI state.
export function discoGradeLetter(pct) {
  if (pct >= 97) return 'A+'; if (pct >= 93) return 'A'; if (pct >= 90) return 'A-';
  if (pct >= 87) return 'B+'; if (pct >= 83) return 'B'; if (pct >= 80) return 'B-';
  if (pct >= 77) return 'C+'; if (pct >= 73) return 'C'; if (pct >= 70) return 'C-';
  if (pct >= 60) return 'D';  return 'F';
}
export function discoGradeWord(pct) {
  if (pct >= 90) return 'Excellent'; if (pct >= 80) return 'Good';
  if (pct >= 70) return 'Fair';      if (pct >= 60) return 'Weak';
  return 'Failing';
}