/**
 * Config -- unified project configuration hub.
 *
 * Config.make() produces a frozen, FNV-1a content-addressed Config.Shape.
 * Projection functions are pure — no side effects, no I/O.
 */

import type { ContentAddress } from './brands.js';
import type { Boundary } from './boundary.js';
import type { Token } from './token.js';
import type { Theme } from './theme.js';
import type { Style } from './style.js';
import { fnv1aBytes } from './fnv.js';
import { CanonicalCbor } from './cbor.js';

// ─────────────────────────────────────────────────────────────────────────────
// Public types
// ─────────────────────────────────────────────────────────────────────────────

/** Top-level discriminator for czap primitives: which bucket a declaration belongs to. */
export type PrimitiveKind = 'boundary' | 'token' | 'theme' | 'style';

/**
 * Vite-plugin slice of a czap {@link Config.Shape}: source directories per
 * primitive kind, HMR opt-in, environment targeting, and optional WASM hints.
 */
export interface PluginConfig {
  readonly dirs?: Partial<Record<PrimitiveKind, string>>;
  readonly hmr?: boolean;
  readonly environments?: readonly ('browser' | 'server' | 'shader')[];
  readonly wasm?: boolean | { readonly enabled?: boolean; readonly path?: string };
}

/** Astro-integration slice of a czap {@link Config.Shape}. */
export interface AstroConfig {
  readonly satellite?: boolean;
  readonly edgeRuntime?: boolean;
}

// ─────────────────────────────────────────────────────────────────────────────
// Config namespace + value object (declaration merging — same pattern as Boundary)
// ─────────────────────────────────────────────────────────────────────────────

/**
 * Config namespace — the single hub that every czap adapter (Vite, Astro, test
 * runners, edge runtime) projects from. {@link Config.make} produces a frozen,
 * FNV-1a content-addressed {@link Config.Shape}; every projection function
 * (`toViteConfig`, `toAstroConfig`, `toTestAliases`) is pure.
 */
export const Config = {
  /** Build a frozen, content-addressed {@link Config.Shape} from raw input. */
  make(input: Config.Input): Config.Shape {
    // CUT B5a — mint the internal identity through the CanonicalCbor doctrine
    // (RFC 8949 §4.2.1, recursive key sort, always-float64), the same path as
    // every other `fnv1a:` content address. This replaces the old top-level-only
    // `JSON.stringify` sort, which left nested non-`id` fields insertion-order
    // dependent. CanonicalCbor sorts keys recursively, so no manual sort is needed.
    const id = fnv1aBytes(
      CanonicalCbor.encode({
        boundaries: input.boundaries ?? {},
        tokens: input.tokens ?? {},
        themes: input.themes ?? {},
        styles: input.styles ?? {},
        vite: input.vite,
        astro: input.astro,
      }),
    );
    return Object.freeze({
      _tag: 'ConfigDef' as const,
      id,
      boundaries: input.boundaries ?? {},
      tokens: input.tokens ?? {},
      themes: input.themes ?? {},
      styles: input.styles ?? {},
      vite: input.vite,
      astro: input.astro,
    });
  },

  /** Project the Vite-plugin slice of a config for `@czap/vite`. */
  toViteConfig(cfg: Config.Shape): PluginConfig {
    return {
      ...(cfg.vite?.dirs !== undefined && { dirs: cfg.vite.dirs }),
      ...(cfg.vite?.hmr !== undefined && { hmr: cfg.vite.hmr }),
      ...(cfg.vite?.environments !== undefined && { environments: cfg.vite.environments }),
      ...(cfg.vite?.wasm !== undefined && { wasm: cfg.vite.wasm }),
    };
  },

  /** Project the Astro-integration slice of a config for `@czap/astro`. */
  toAstroConfig(cfg: Config.Shape): AstroConfig {
    return {
      ...(cfg.astro?.satellite !== undefined && { satellite: cfg.astro.satellite }),
      ...(cfg.astro?.edgeRuntime !== undefined && { edgeRuntime: cfg.astro.edgeRuntime }),
    };
  },

  /** Materialize the `@czap/*` → source-path alias map used by the vitest runner. */
  toTestAliases(cfg: Config.Shape, repoRoot: string): Record<string, string> {
    void cfg; // cfg reserved for future per-project customisation
    // Distinct op (NOT repo-path normalization, CUT B5b): a vitest-alias URL join.
    // Kept inline on purpose — @czap/core is product runtime and must NOT import the
    // devops-layer @czap/audit normalizeRepoPath. Forward-slash join for portability.
    const r = (sub: string) => `${repoRoot.replace(/\\/g, '/')}/${sub}`;
    // NOTE: longer prefixes MUST come before shorter ones — vitest's alias
    // resolver matches the first prefix in iteration order, so e.g.
    // `@czap/core/testing` would be intercepted by `@czap/core` if listed first.
    return {
      '@czap/canonical': r('packages/canonical/src/index.ts'),
      '@czap/genui': r('packages/genui/src/index.ts'),
      '@czap/core/testing': r('packages/core/src/testing.ts'),
      '@czap/core/harness': r('packages/core/src/harness/index.ts'),
      '@czap/core/simulation': r('packages/core/src/simulation/index.ts'),
      '@czap/core': r('packages/core/src/index.ts'),
      '@czap/quantizer/testing': r('packages/quantizer/src/testing.ts'),
      '@czap/quantizer': r('packages/quantizer/src/index.ts'),
      '@czap/compiler': r('packages/compiler/src/index.ts'),
      '@czap/web/lite': r('packages/web/src/lite.ts'),
      '@czap/web': r('packages/web/src/index.ts'),
      '@czap/detect': r('packages/detect/src/index.ts'),
      '@czap/vite/html-transform': r('packages/vite/src/html-transform.ts'),
      '@czap/vite': r('packages/vite/src/index.ts'),
      '@czap/astro/runtime': r('packages/astro/src/runtime/index.ts'),
      '@czap/astro': r('packages/astro/src/index.ts'),
      '@czap/stage/ffmpeg': r('packages/stage/src/ffmpeg.ts'),
      '@czap/stage': r('packages/stage/src/index.ts'),
      '@czap/remotion': r('packages/remotion/src/index.ts'),
      '@czap/scene/dev': r('packages/scene/src/dev/server.ts'),
      '@czap/scene': r('packages/scene/src/index.ts'),
      '@czap/assets': r('packages/assets/src/index.ts'),
      '@czap/audit': r('packages/audit/src/index.ts'),
      '@czap/cli': r('packages/cli/src/index.ts'),
      '@czap/mcp-server': r('packages/mcp-server/src/index.ts'),
      '@czap/edge': r('packages/edge/src/index.ts'),
      '@czap/cloudflare/testing': r('packages/cloudflare/src/testing.ts'),
      '@czap/cloudflare': r('packages/cloudflare/src/index.ts'),
      '@czap/worker': r('packages/worker/src/index.ts'),
      '@czap/_spine': r('packages/_spine'),
    };
  },
};

export declare namespace Config {
  /** Raw user-facing input to {@link Config.make} — every field is optional. */
  interface Input {
    readonly boundaries?: Record<string, Boundary.Shape>;
    readonly tokens?: Record<string, Token.Shape>;
    readonly themes?: Record<string, Theme.Shape>;
    readonly styles?: Record<string, Style.Shape>;
    readonly vite?: Partial<PluginConfig>;
    readonly astro?: Partial<AstroConfig>;
  }

  /** Frozen, content-addressed result of {@link Config.make}. */
  interface Shape {
    readonly _tag: 'ConfigDef';
    readonly id: ContentAddress;
    readonly boundaries: Record<string, Boundary.Shape>;
    readonly tokens: Record<string, Token.Shape>;
    readonly themes: Record<string, Theme.Shape>;
    readonly styles: Record<string, Style.Shape>;
    readonly vite?: Partial<PluginConfig>;
    readonly astro?: Partial<AstroConfig>;
  }
}

/** Thin alias for {@link Config.make} — matches the `defineConfig(...)` ergonomics other tools use. */
export function defineConfig(input: Config.Input): Config.Shape {
  return Config.make(input);
}