import { NAMZU } from '../constants/telemetry/index.js'
import { SCOPE_ATTRIBUTE } from '../utils/log/types.js'
import { type Logger, resolveLogger } from '../utils/logger.js'
import { BaseRegistry } from './BaseRegistry.js'

export interface ManagedRegistryConfig<TDefinition> {
	componentName: string
	idField?: keyof TDefinition & string
	/**
	 * Extract id from a full item. Takes precedence over `idField` when provided.
	 * Required when the id field is nested (e.g. `def.info.id`).
	 */
	computeId?: (item: TDefinition) => string
	logger?: Logger
}

export class ManagedRegistry<TDefinition> extends BaseRegistry<TDefinition> {
	protected log: Logger
	private idField?: keyof TDefinition & string
	private computeId?: (item: TDefinition) => string

	constructor(config: ManagedRegistryConfig<TDefinition>) {
		super()
		this.idField = config.idField
		this.computeId = config.computeId
		this.log = resolveLogger(config.logger).child({
			[SCOPE_ATTRIBUTE]: 'registry',
			[NAMZU.REGISTRY_NAME]: config.componentName,
		})
	}

	override register(id: string, item: TDefinition): void
	override register(item: TDefinition): void
	override register(items: TDefinition[]): void
	override register(idOrItem: string | TDefinition | TDefinition[], maybeItem?: TDefinition): void {
		if (Array.isArray(idOrItem)) {
			for (const item of idOrItem) {
				this.register(item)
			}
			return
		}

		if (typeof idOrItem === 'string') {
			if (!maybeItem) {
				throw new Error('register(id, item) requires an item argument')
			}
			const id = idOrItem
			const item = maybeItem
			if (this.has(id)) {
				this.log.warn('Already registered, overwriting', { 'namzu.registry.item_id': id })
			}
			super.register(id, item)
			this.log.debug('Registered', { 'namzu.registry.item_id': id })
			return
		}

		const item = idOrItem
		const id = this.computeId
			? this.computeId(item)
			: this.idField
				? String(item[this.idField])
				: undefined
		if (id === undefined) {
			throw new Error('register(item) requires idField or computeId to be configured')
		}

		if (this.has(id)) {
			this.log.warn('Already registered, overwriting', { 'namzu.registry.item_id': id })
		}
		super.register(id, item)
		// `debug`, not `info`. Registration is the startup path doing exactly
		// what it is supposed to do, once per item, and there are dozens: a
		// default-level run opened with twenty `Registered` lines, one per
		// tool, before anything an operator could act on. That is the same
		// failure as silence with the sign flipped — the interesting lines are
		// there, and nobody can find them.
		//
		// The overwrite case above stays at `warn`, because a second
		// registration under a live id IS news.
		//
		// Found by running the CLI against a real provider rather than a mock.
		// Every unit test here asserts on a logger stub, so the LEVEL was
		// invisible to all of them: what a start actually reads like is not a
		// property any of them measure.
		this.log.debug('Registered', { 'namzu.registry.item_id': id })
	}

	getOrThrow(id: string): TDefinition {
		const item = this.get(id)
		if (!item) {
			throw new Error(`Not found: "${id}". Available: ${this.listIds().join(', ')}`)
		}
		return item
	}
}