// Integration-registry API client (operator surface).
//
// Talks to arcadia-llm-gateway's `/api/v1/integrations*` endpoints — the
// platform operator manages pooled/platform credentials at ANY scope and
// inspects cross-tenant usage *metadata* (never secrets; reads return
// `has_secret`, never a value).
//
// The tenant mirror (`/api/v1/me/integrations*`, scoped to the caller) lives
// in arcadia-console. Pure functions over an injected gateway `ArcadiaClient`
// (see `~/lib/gateway`); no app coupling, so this lifts into a shared lib once
// both apps exist.

import type { ArcadiaClient } from "@crema/arcadia-client"

export type Scope = "platform" | "tenant" | "app" | "user" | "agent"
export type AuthKind = "bearer_static" | "basic" | "api_key_header" | "oauth2"
export type CredentialSource = "byo" | "pooled"
export type CredentialStatus = "active" | "expired" | "revoked"

export interface CostModel {
  unit?: "call" | "search" | "1k_tokens"
  price_usd?: string | number
  currency?: string
}

export interface Constraints {
  rate_per_min?: number
  monthly_budget_usd?: string | number
  monthly_call_cap?: number
}

export interface Credential {
  id: string
  integration_id: string
  secret_name: string
  auth_kind: AuthKind
  meta: Record<string, unknown>
  /** Presence, not value — the secret is write-only. */
  has_secret: boolean
  expires_at: string | null
  last_rotated_at: string | null
  source: CredentialSource
  status: CredentialStatus
}

export interface Integration {
  id: string
  scope: Scope
  scope_id: string | null
  provider: string
  capability: string | null
  display_name: string | null
  description: string | null
  docs_url: string | null
  base_url: string | null
  enabled: boolean
  cost_model: CostModel
  constraints: Constraints
  created_by: string | null
  credentials: Credential[]
}

export interface UsageEntry {
  integration_id: string
  scope: Scope
  scope_id: string | null
  provider: string
  capability: string | null
  units: number
  cost_usd: string
  calls: number
}

export interface IntegrationInput {
  scope?: Scope
  scope_id?: string | null
  provider: string
  capability?: string | null
  display_name?: string | null
  description?: string | null
  docs_url?: string | null
  base_url?: string | null
  enabled?: boolean
  cost_model?: CostModel
  constraints?: Constraints
}

export interface CredentialInput {
  secret_name: string
  auth_kind: AuthKind
  /** Plaintext, write-only — sent on create/rotate, never returned. */
  secret?: string
  source?: CredentialSource
  expires_at?: string | null
  meta?: Record<string, unknown>
}

export interface TestVerdict {
  status: string
  auth_kind?: AuthKind
  policy?: {
    within_budget: boolean
    within_rate: boolean
    remaining_budget_usd: string | null
  }
}

export interface ScopeFilter {
  scope?: Scope
  scope_id?: string
}

const BASE = "/api/v1/integrations"

export async function listIntegrations(
  c: ArcadiaClient,
  filter: ScopeFilter = {},
): Promise<Integration[]> {
  const res = await c.GET<{ integrations: Integration[] }>(BASE, {
    params: { scope: filter.scope, scope_id: filter.scope_id },
  })
  return res.integrations
}

export async function createIntegration(
  c: ArcadiaClient,
  input: IntegrationInput,
): Promise<Integration> {
  const res = await c.POST<{ integration: Integration }>(BASE, { body: input })
  return res.integration
}

export async function updateIntegration(
  c: ArcadiaClient,
  id: string,
  input: Partial<IntegrationInput>,
): Promise<Integration> {
  const res = await c.PATCH<{ integration: Integration }>(`${BASE}/${id}`, { body: input })
  return res.integration
}

export async function deleteIntegration(c: ArcadiaClient, id: string): Promise<void> {
  await c.DELETE(`${BASE}/${id}`)
}

export async function addCredential(
  c: ArcadiaClient,
  integrationId: string,
  input: CredentialInput,
): Promise<Credential> {
  const res = await c.POST<{ credential: Credential }>(`${BASE}/${integrationId}/credentials`, {
    body: input,
  })
  return res.credential
}

export async function updateCredential(
  c: ArcadiaClient,
  credentialId: string,
  input: Partial<CredentialInput>,
): Promise<Credential> {
  const res = await c.PATCH<{ credential: Credential }>(`/api/v1/credentials/${credentialId}`, {
    body: input,
  })
  return res.credential
}

export async function deleteCredential(c: ArcadiaClient, credentialId: string): Promise<void> {
  await c.DELETE(`/api/v1/credentials/${credentialId}`)
}

/**
 * Run the registry's policy gate against an integration's credential. 200 with
 * a verdict; 4xx (409 expired / 429 over-budget / 404 no credential) is thrown
 * by `ArcadiaClient` as an `ArcadiaError` — inspect `err.status`.
 */
export async function testIntegration(c: ArcadiaClient, id: string): Promise<TestVerdict> {
  return c.POST<TestVerdict>(`${BASE}/${id}/test`)
}

export async function usageSummary(
  c: ArcadiaClient,
  filter: ScopeFilter = {},
): Promise<UsageEntry[]> {
  const res = await c.GET<{ usage: UsageEntry[] }>(`${BASE}/usage`, {
    params: { scope: filter.scope, scope_id: filter.scope_id },
  })
  return res.usage
}

// ── display helpers ────────────────────────────────────────────────────

export function formatUsd(value: string | number | null | undefined): string {
  if (value === null || value === undefined) return "—"
  const n = typeof value === "string" ? Number(value) : value
  if (Number.isNaN(n)) return "—"
  return `$${n.toFixed(n < 0.01 && n > 0 ? 4 : 2)}`
}

export function credentialHealth(cred: Credential): "ok" | "expired" | "revoked" | "missing" {
  if (cred.status === "revoked") return "revoked"
  if (!cred.has_secret) return "missing"
  if (cred.expires_at && new Date(cred.expires_at).getTime() < Date.now()) return "expired"
  return "ok"
}