# Knowledge Graph Data Model — D-041
# Per-entity bevy_ecs Component with BTreeMap storage.
# Confidence hierarchy, knowledge state, knowledge source, event-driven updates.

vars: {
  color-bg: "#2a3040"
  color-stroke: "#333340"
  color-text: "#c8d0e0"
  color-accent: "#c8d8f0"
  color-dim: "#1a1e24"
}

KnowledgeGraph: KnowledgeGraph {
  shape: sql_table
  entity_knowledge: BTreeMap<StableId, EntityKnowledge>
  fact_knowledge: BTreeMap<FactId, FactKnowledge>
}

EntityKnowledge: EntityKnowledge {
  shape: sql_table
  stable_id: StableId(u64) {constraint: foreign_key}
  confidence: KnowledgeConfidence
  state: KnowledgeState
  source: KnowledgeSource
  last_observed_tick: u64
}

FactKnowledge: FactKnowledge {
  shape: sql_table
  fact_id: FactId {constraint: primary_key}
  confidence: KnowledgeConfidence
  state: KnowledgeState
  source: KnowledgeSource
  last_observed_tick: u64
}

KnowledgeConfidence: KnowledgeConfidence {
  shape: sql_table
  direct: Direct — currently in LOS
  knows_details: KnowsDetails — actionable (secret tier)
  knows_of: KnowsOf — involved in Y (real tier)
  suspects: Suspects — something off (surface tier)
}

KnowledgeState: KnowledgeState {
  shape: sql_table
  active: Active — believed true
  contradicted: Contradicted — conflict detected (Sprint 3+)
  stale: Stale — aged beyond threshold (Sprint 3+)
}

KnowledgeSource: KnowledgeSource {
  shape: sql_table
  direct_observation: DirectObservation
  heard: Heard
  told_by: ToldBy (Sprint 3+)
  inferred: Inferred (Sprint 3+)
  background: Background
}

EntityRegistry: EntityRegistry {
  shape: sql_table
  stable_to_entity: BTreeMap<StableId, Entity>
  entity_to_stable: BTreeMap<Entity, StableId>
}

KnowledgeEventQueue: KnowledgeEventQueue\n(bevy_ecs Resource) {
  shape: queue
  style.fill: ${color-dim}
  style.stroke: ${color-accent}
  style.font-color: ${color-text}
}

KnowledgeGraph -> EntityKnowledge: "contains many"
KnowledgeGraph -> FactKnowledge: "contains many"
EntityKnowledge -> KnowledgeConfidence: "uses"
EntityKnowledge -> KnowledgeState: "uses"
EntityKnowledge -> KnowledgeSource: "uses"
FactKnowledge -> KnowledgeConfidence: "uses"
FactKnowledge -> KnowledgeState: "uses"
FactKnowledge -> KnowledgeSource: "uses"
EntityKnowledge -> EntityRegistry: "StableId lookup" {
  style.stroke: ${color-accent}
  style.stroke-dash: 4
}
KnowledgeEventQueue -> KnowledgeGraph: "drained each tick\n→ writes components" {
  style.stroke: ${color-accent}
}