// Per-kind presentation, shared by the tree, the overview, and anywhere else
// a note's kind needs to be shown at a glance.
//
// Kind is encoded by **icon shape**, not colour. Three categories would be a
// categorical palette, and at the 12px mark size the tree uses, colour alone
// is the least reliable channel there is — it fails for colour-vision
// deficiency, and small low-chroma marks on a dark surface are hard for
// anyone to tell apart. Distinct silhouettes are legible at any size, in any
// theme, for every reader. Colour is left to carry state (selection, the
// agent badge), where it isn't the only thing distinguishing two items.
//
// It also fixes a plain redundancy: the tree previously stamped a literal
// "document" text badge on every row, which in a folder of 20 documents is
// 20 repetitions of the same word and no information at all.
import FileTextIcon from '@lucide/svelte/icons/file-text'
import MicroscopeIcon from '@lucide/svelte/icons/microscope'
import ListChecksIcon from '@lucide/svelte/icons/list-checks'
import type { Component } from 'svelte'

export type NoteKind = 'document' | 'investigation' | 'runbook'

export interface KindMeta {
  icon: Component
  label: string
  /** Plural, for counts and section headings. */
  plural: string
}

const FALLBACK: KindMeta = { icon: FileTextIcon, label: 'note', plural: 'notes' }

const KIND_META: Record<NoteKind, KindMeta> = {
  document: { icon: FileTextIcon, label: 'document', plural: 'documents' },
  investigation: { icon: MicroscopeIcon, label: 'investigation', plural: 'investigations' },
  runbook: { icon: ListChecksIcon, label: 'runbook', plural: 'runbooks' }
}

// Tolerates an unknown kind rather than throwing — `kind` comes from the
// entity's type column, which the ontology could grow a fourth value for
// without this file knowing.
export function kindMeta(kind: string): KindMeta {
  return KIND_META[kind as NoteKind] ?? FALLBACK
}

// True for notes last written by the agent rather than a human. Two spellings
// exist in the live data: 'nomos-agent' (written via the MCP upsert_knowledge
// tool) and 'agent:mcp' (the actor label the HTTP API records when the same
// agent calls in over REST with the MCP bearer token).
export function isAgentAuthored(editedBy: string): boolean {
  return editedBy === 'nomos-agent' || editedBy === 'agent:mcp'
}