import { z } from "zod";

import { contractSetSchema } from "./contract-set.ts";

const versionSchema = z.string().regex(/^\d+(?:\.\d+){0,2}$/);

function assertEndpointUrl(
  value: string,
  local: boolean,
  options: Readonly<{ trailingSlashPath?: boolean }> = {},
): void {
  const parsed = new URL(value);
  if (
    (parsed.protocol !== "http:" && parsed.protocol !== "https:") ||
    parsed.username ||
    parsed.password ||
    parsed.hash ||
    parsed.search ||
    (!local && parsed.protocol !== "https:")
  ) {
    throw new TypeError("invalid");
  }
  if (options.trailingSlashPath && !parsed.pathname.endsWith("/")) {
    throw new TypeError("invalid");
  }
}

export function isValidReleaseManifestUrl(value: string): boolean {
  if (!value.startsWith("/") || value.startsWith("//")) return false;
  if (new TextEncoder().encode(value).byteLength > 256) return false;
  if (value.includes("?") || value.includes("#") || value.includes("\\")) {
    return false;
  }
  if (/%2f|%5c/i.test(value)) return false;
  return !value
    .split("/")
    .some((segment) => segment === "." || segment === "..");
}

export const capabilityOverrideArtifactSchema = z
  .object({
    REALTIME: z.enum(["DEFAULT", "DISABLED"]).default("DEFAULT"),
    WEB_WORKER: z.enum(["DEFAULT", "DISABLED"]).default("DEFAULT"),
    SERVICE_WORKER: z.enum(["DEFAULT", "DISABLED"]).default("DEFAULT"),
    OFFLINE_COMMANDS: z.enum(["DEFAULT", "DISABLED"]).default("DEFAULT"),
  })
  .strict()
  .default({
    REALTIME: "DEFAULT",
    WEB_WORKER: "DEFAULT",
    SERVICE_WORKER: "DEFAULT",
    OFFLINE_COMMANDS: "DEFAULT",
  });

/**
 * §3.5 / §6.1. A runtime switch that can take an installed feature out of
 * service without a rebuild.
 *
 * Values are `DEFAULT | DISABLED` for the same reason `CAPABILITY_OVERRIDES`
 * is: a configuration document may subtract from what the build installed and
 * may never add to it. Keys are feature ids; naming a feature this build does
 * not contain is inert rather than an error, so a shared configuration
 * document can cover several builds.
 */
export const featureOverrideArtifactSchema = z
  .record(
    z.string().regex(/^[a-z][a-z0-9-]{0,63}$/u, "feature id is invalid"),
    z.enum(["DEFAULT", "DISABLED"]),
  )
  .default({});

type RuntimeConfigArtifactDraft = Readonly<{
  APP_ENV: "local" | "development" | "staging" | "production";
  API_BASE_URL: string;
  TELEMETRY_ENABLED: boolean;
  TELEMETRY_ENDPOINT?: string;
  AUTH_MODE: "external" | "demo";
  RELEASE_MANIFEST_URL: string;
}>;

function runtimeConfigArtifactInvariants(
  config: RuntimeConfigArtifactDraft,
  context: z.RefinementCtx,
): void {
  const local = config.APP_ENV === "local" || config.APP_ENV === "development";
  if (config.TELEMETRY_ENABLED && !config.TELEMETRY_ENDPOINT) {
    context.addIssue({
      code: "custom",
      path: ["TELEMETRY_ENDPOINT"],
      message: "required when telemetry is enabled",
    });
  }
  if (!local && config.AUTH_MODE === "demo") {
    context.addIssue({
      code: "custom",
      path: ["AUTH_MODE"],
      message: "demo authentication is limited to local environments",
    });
  }
  try {
    assertEndpointUrl(config.API_BASE_URL, local, { trailingSlashPath: true });
  } catch {
    context.addIssue({
      code: "custom",
      path: ["API_BASE_URL"],
      message:
        "absolute credential-free URL ending in / is required; HTTPS outside local",
    });
  }
  if (config.TELEMETRY_ENDPOINT) {
    try {
      assertEndpointUrl(config.TELEMETRY_ENDPOINT, local);
    } catch {
      context.addIssue({
        code: "custom",
        path: ["TELEMETRY_ENDPOINT"],
        message:
          "absolute credential-free URL is required; HTTPS outside local",
      });
    }
  }
  if (!isValidReleaseManifestUrl(config.RELEASE_MANIFEST_URL)) {
    context.addIssue({
      code: "custom",
      path: ["RELEASE_MANIFEST_URL"],
      message: "same-origin absolute path without query, hash or traversal",
    });
  }
}

const runtimeConfigArtifactFields = {
  APP_ENV: z.enum(["local", "development", "staging", "production"]),
  API_BASE_URL: z.url(),
  REQUEST_TIMEOUT_MS: z.int().min(100).max(60_000).default(10_000),
  MAX_RETRY_ATTEMPTS: z.int().min(0).max(2).default(2),
  TELEMETRY_ENABLED: z.boolean(),
  TELEMETRY_ENDPOINT: z.url().optional(),
  AUTH_MODE: z.enum(["external", "demo"]),
  RELEASE_MANIFEST_URL: z.string().min(1).default("/release-manifest.json"),
  RELEASE_ID: z.string().min(1).optional(),
  BUILD_ID: z.string().min(1).optional(),
} as const;

export const runtimeConfigV1ArtifactSchema = z
  .object({
    ...runtimeConfigArtifactFields,
    CONFIG_SCHEMA_VERSION: z.literal("1"),
    API_CONTRACT_VERSION: versionSchema,
  })
  .strict()
  .superRefine(runtimeConfigArtifactInvariants);

export const runtimeConfigV2ArtifactSchema = z
  .object({
    ...runtimeConfigArtifactFields,
    CONFIG_SCHEMA_VERSION: z.literal("2.0"),
    CAPABILITY_OVERRIDES: capabilityOverrideArtifactSchema,
    FEATURE_OVERRIDES: featureOverrideArtifactSchema,
  })
  .strict()
  .superRefine(runtimeConfigArtifactInvariants);

export const runtimeConfigArtifactSchema = z.discriminatedUnion(
  "CONFIG_SCHEMA_VERSION",
  [
  runtimeConfigV1ArtifactSchema,
  runtimeConfigV2ArtifactSchema,
  ],
);

const releaseManifestArtifactFields = {
  appVersion: z.string().min(1),
  buildId: z.string().min(1),
  commitSha: z.string().min(1),
  assetManifestHash: z.string().min(1),
  releaseId: z.string().min(1),
  builtAt: z.string().min(1),
  routeChunks: z.record(z.string().min(1), z.string().min(1)),
} as const;

export const releaseManifestV1ArtifactSchema = z
  .object({
    schemaVersion: z.literal(1),
    ...releaseManifestArtifactFields,
    configSchemaVersion: versionSchema,
    apiContractVersion: versionSchema,
  })
  .strict();

export const releaseManifestV2ArtifactSchema = z
  .object({
    schemaVersion: z.literal(2),
    ...releaseManifestArtifactFields,
    configSchemaVersion: z.literal("2.0"),
    contractSet: contractSetSchema,
  })
  .strict();

export const releaseManifestArtifactSchema = z.discriminatedUnion(
  "schemaVersion",
  [releaseManifestV1ArtifactSchema, releaseManifestV2ArtifactSchema],
);

export const buildManifestArtifactSchema = z
  .object({
    schemaVersion: z.literal(1),
    buildId: z.string().min(1),
    commitSha: z.string().min(1),
    releaseId: z.string().min(1),
    moduleInventoryHash: z.string().min(1),
    generatedAt: z.string().min(1),
    buildContext: z
      .object({
        nodeVersion: z.string().min(1),
        packageManagerVersion: z.string().min(1),
        runnerImage: z.string().min(1),
        sourceDateEpoch: z.string().min(1).nullable(),
      })
      .strict(),
    outputs: z
      .object({
        directory: z.string().min(1),
        viteManifest: z.string().min(1),
        moduleInventory: z.string().min(1),
        routeChunks: z.record(z.string().min(1), z.string().min(1)),
        runtimeConfigSchema: z.string().min(1),
      })
      .strict(),
  })
  .strict();

export type RuntimeConfigV1Artifact = z.output<
  typeof runtimeConfigV1ArtifactSchema
>;
export type RuntimeConfigV2Artifact = z.output<
  typeof runtimeConfigV2ArtifactSchema
>;
export type CapabilityOverrideArtifact = z.output<
  typeof capabilityOverrideArtifactSchema
>;
export type RuntimeConfigArtifact = z.output<typeof runtimeConfigArtifactSchema>;
export type ReleaseManifestV1Artifact = z.output<
  typeof releaseManifestV1ArtifactSchema
>;
export type ReleaseManifestV2Artifact = z.output<
  typeof releaseManifestV2ArtifactSchema
>;
export type ReleaseArtifact = z.output<typeof releaseManifestArtifactSchema>;
export type BuildManifestArtifact = z.output<typeof buildManifestArtifactSchema>;

export function parseReleaseArtifact(value: unknown): ReleaseArtifact {
  return releaseManifestArtifactSchema.parse(value);
}

export function parseRuntimeConfigArtifact(value: unknown): RuntimeConfigArtifact {
  return runtimeConfigArtifactSchema.parse(value);
}

export function parseBuildManifestArtifact(value: unknown): BuildManifestArtifact {
  return buildManifestArtifactSchema.parse(value);
}

export function projectReleaseTokens(release: ReleaseArtifact) {
  const common = {
    schemaVersion: release.schemaVersion,
    appVersion: release.appVersion,
    buildId: release.buildId,
    commitSha: release.commitSha,
    configSchemaVersion: release.configSchemaVersion,
    assetManifestHash: release.assetManifestHash,
    releaseId: release.releaseId,
    builtAt: release.builtAt,
  } as const;

  return release.schemaVersion === 1
    ? Object.freeze({
        ...common,
        schemaVersion: 1 as const,
        apiContractVersion: release.apiContractVersion,
      })
    : Object.freeze({
        ...common,
        schemaVersion: 2 as const,
        contractSetDigest: release.contractSet.setDigest,
      });
}