"use client"

/**
 * KeyMetricsProvider — host-app injection point for the design-system
 * `KeyMetrics` component.
 *
 * `KeyMetrics` itself ships as a pure primitive: it knows how to render
 * a KPI strip, an insight rail, and a default insight CTA, but it does
 * NOT know anything about the host app's AI assistant, command palette,
 * or keyboard-shortcut registry.
 *
 * Consumers (e.g. `apps/web`) mount a `KeyMetricsProvider` near the root
 * of the app and supply two optional injection points:
 *
 *  - `defaultInsightAction` — fired when the user clicks the default
 *    "Ask Leo about these metrics" button in the card-variant header,
 *    and the default insight CTA when an individual `MetricInsight` did
 *    not supply its own `onAction`. When omitted, the default button is
 *    hidden entirely so the primitive stays useful in apps without an
 *    AI assistant.
 *
 *  - `shortcutHint` — inline React node rendered inside the tooltip
 *    alongside the action label (typically a keyboard chord such as
 *    `<Kbd>⌘⌥K</Kbd>`). When omitted, the tooltip simply shows the
 *    label.
 *
 *  - `defaultActionLabel` — visible label + accessible name for the
 *    default action button. Defaults to "Ask Leo" so the existing
 *    Exxat-DS layout reads identically without any consumer changes.
 *
 * This is the SAME injection shape used by Adobe Spectrum
 * (`Provider`-based service injection) and Material UI (`Theme`
 * context). It lets the design-system package ship product patterns
 * without taking on a hard dependency on the host app's AI surface.
 */

import * as React from "react"

export interface KeyMetricsContextValue {
  /** Click handler for the default "Ask Leo about these metrics" CTA. */
  defaultInsightAction?: () => void
  /** Inline kbd chord (or any node) rendered next to the action label inside the tooltip. */
  shortcutHint?: React.ReactNode
  /** Label + aria-label for the default insight action button. Defaults to "Ask Leo". */
  defaultActionLabel?: string
}

const KeyMetricsContext = React.createContext<KeyMetricsContextValue>({})

/** Read the active `KeyMetricsProvider` value. Returns an empty object if no provider is mounted. */
export function useKeyMetricsContext(): KeyMetricsContextValue {
  return React.useContext(KeyMetricsContext)
}

export function KeyMetricsProvider({
  value,
  children,
}: {
  value: KeyMetricsContextValue
  children: React.ReactNode
}) {
  // Memoize the wrapper so consumers passing fresh object identities
  // (common in client components) do not invalidate every descendant
  // that reads the context.
  const memo = React.useMemo<KeyMetricsContextValue>(
    () => ({
      defaultInsightAction: value.defaultInsightAction,
      shortcutHint: value.shortcutHint,
      defaultActionLabel: value.defaultActionLabel,
    }),
    [value.defaultInsightAction, value.shortcutHint, value.defaultActionLabel],
  )
  return (
    <KeyMetricsContext.Provider value={memo}>
      {children}
    </KeyMetricsContext.Provider>
  )
}