services

Reactive Data & State Services (apps/wiki-graph/src/app/services)

This directory contains the core services responsible for fetching static wiki manifests, parsing raw markdown documents and [[wikilink]] references, and maintaining centralized reactive state using Angular Signals.

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🏛️ Data Pipeline & Reactive State Architecture

1. Document Parsing & Pipeline (WikiParserService)

• Parallel Manifest Fetching: Asynchronously retrieves wiki/manifest.json and loads individual markdown page files concurrently.
• Wikilink & Frontmatter Extraction: Parses YAML metadata headers and extracts [[wikilink]] target strings to construct directed reference edges.
• Graph Transformation: Transforms raw markdown payloads into fully resolved GraphData, calculating incoming/outgoing degree counts, identifying ghost nodes, and aggregating unique tags.

2. Centralized Signal State Store (GraphStateService)

• Single Source of Truth: Manages application state using Angular Signals (graphData, selectedNode, activeTypeFilters, searchQuery, activeTagFilter).
• Computed Subsets: Derives reactive computed signals for filtered node subsets, top connected hub pages, and isolated orphan pages (degree 0) in real time.
• State Actions: Exposes reactive action handlers for search input changes, node selection, tag filter toggling, and reset triggers.

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💡 Functional Capabilities

• Automated Ghost Node Synthesis: Detects uncreated wikilink targets and synthesizes placeholder ghost nodes with dashed encodings.
• Real-Time Reactive Filtering: Combines title search queries, multi-select node type filters (entity, concept, source), and tag selections seamlessly into a computed node view.
• Hub & Orphan Analytics: Identifies highly connected central knowledge hubs and isolated unlinked documents for targeted maintenance.

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📁 File Index

File	Conceptual & Functional Purpose
./wiki-parser.service.ts	HTTP client service fetching manifests, parsing markdown frontmatter, and extracting wikilinks.
./graph-state.service.ts	Centralized Signal state store managing graph selection, filtering, computed views, and analytics.
./wiki-parser.service.spec.ts	Unit test suite validating wikilink extraction, frontmatter parsing, and error handling.
./graph-state.service.spec.ts	Unit test suite verifying signal state reactivity, multi-criteria filtering, and computed signals.