/**
 * earth-now.co
 * Author:  Simon-Pierre Boucher
 * Contact: contact@spboucher.ai
 * File:    packages/registry/src/schema.ts
 * Purpose: Zod schemas for the metric registry YAML and the data fixtures — a metric does not exist until it validates here
 */

import { z } from "zod";

export const sourceSchema = z.object({
  id: z.string().min(1),
  name: z.string().min(1),
  url: z.string().url(),
  license: z.string().min(1),
  /** Set when the license needs a human re-check before public launch. */
  licenseNote: z.string().optional(),
  cadence: z.string().min(1),
  variants: z.array(z.string()).optional(),
});

export const displaySchema = z.object({
  decimals: z.number().int().min(0).max(6),
  sigFigs: z.number().int().min(1).max(15).optional(),
  /** Display conversion factor (t → Gt = 1e-9). NEVER applied in the pipeline. */
  scale: z.number().positive().optional(),
  unit: z.object({ fr: z.string(), en: z.string() }),
});

export const derivedSchema = z.object({
  op: z.enum(["linear-combination", "window", "rate-of", "depletion-countdown"]),
  inputs: z.array(z.object({ id: z.string(), weight: z.number().default(1) })).min(1),
  constant: z.number().optional(),
  /** For op=window: which window is this metric's primary reading. */
  window: z.enum(["today", "ytd", "session"]).optional(),
});

export const metricSchema = z.object({
  id: z.string().regex(/^[a-z0-9_]+$/),
  name: z.object({ fr: z.string().min(1), en: z.string().min(1) }),
  domain: z.enum([
    "population",
    "climate",
    "emissions",
    "forest",
    "ocean",
    "energy",
    "society",
    "health",
    "economy",
    "tech",
    "realtime",
    "space",
  ]),
  priority: z.enum(["mvp", "v1", "v2"]),
  kind: z.enum(["stock", "cumulative", "event", "derived"]),
  /** Model level from the catalog: 0/1/2 statistical, "rt" true event-driven, "derived". */
  level: z.union([z.literal(0), z.literal(1), z.literal(2), z.literal("rt"), z.literal("derived")]),
  /** Model family (must match a builder in packages/models), or "derived"/"rt". */
  model: z.string().min(1),
  /** Data-layer unit (SI or domain standard); display conversions live in display. */
  unit: z.string().min(1),
  sources: z.array(sourceSchema).min(1),
  refresh: z.string().min(1),
  display: displaySchema,
  constraints: z
    .object({
      maxAbsRatePerSec: z.number().positive().optional(),
      maxJumpOnRefit: z.number().positive().optional(),
    })
    .default({}),
  windows: z.array(z.enum(["total", "today", "ytd", "session"])).default(["total"]),
  derived: derivedSchema.optional(),
  /** Relative 90 % CI to surface in the UI ("estimation" label mandatory when set). */
  uncertaintyFraction: z.number().positive().max(1).optional(),
  editorialNote: z.object({ fr: z.string(), en: z.string() }).optional(),
});

export const metricsFileSchema = z.object({ metrics: z.array(metricSchema).min(1) });

export type MetricEntry = z.infer<typeof metricSchema>;
export type SourceEntry = z.infer<typeof sourceSchema>;

const timeValueSchema = z.object({ time: z.string(), value: z.number() });

export const fixtureSchema = z.discriminatedUnion("family", [
  z.object({
    family: z.literal("seasonal-spline-v2"),
    observations: z.array(timeValueSchema).min(1),
    forecasts: z.array(timeValueSchema).min(1),
    uncertainty: z.object({ low: z.number(), high: z.number() }).optional(),
    observedAt: z.string(),
  }),
  z.object({
    family: z.literal("keeling-fusion-v1"),
    observations: z.array(timeValueSchema).min(6),
    observedAt: z.string(),
  }),
  z.object({
    family: z.literal("seasonal-ytd-v1"),
    year: z.number().int(),
    annualTotal: z.number().nonnegative(),
    shape: z.array(
      z.object({
        period: z.enum(["year", "week", "day"]),
        order: z.number().int().min(1),
        relativeAmplitude: z.number(),
        phase: z.number(),
      }),
    ),
    observedAt: z.string(),
  }),
  z.object({
    family: z.literal("linear-ytd-v1"),
    year: z.number().int(),
    annualTotal: z.number().nonnegative(),
    observedAt: z.string(),
  }),
  z.object({
    family: z.literal("linear-stock-v1"),
    at: z.string(),
    value: z.number(),
    perSecond: z.number(),
    observedAt: z.string(),
  }),
  z.object({
    family: z.literal("static-rt-v1"),
    at: z.string(),
    value: z.number(),
    observedAt: z.string(),
  }),
]);

export type MetricFixture = z.infer<typeof fixtureSchema>;

export const fixturesFileSchema = z.record(z.string(), fixtureSchema);