// Curated tool surface the assistant can call. The LLM emits a fenced
// ```tool block with one JSON object per line; we parse, execute via
// arcadia-client, and feed results back as the next user turn.
//
// Each tool is a named function with documented args. The LLM never sees
// raw HTTP — only the menu below.

import type { ArcadiaClient } from "@crema/arcadia-client"
import type { Tool, ToolCall as LLMToolCall } from "@crema/llm-ui"

import { getTenant, listTenants, type Tenant } from "~/lib/arcadia/tenants"

export type ToolCall = {
  name: string
  args: Record<string, unknown>
}

export type ToolResult = {
  name: string
  args: Record<string, unknown>
  ok: boolean
  data?: unknown
  error?: string
}

type ToolDef = {
  name: string
  description: string
  parameters: Record<string, unknown> // JSON Schema for OpenAI tool calling
  isWrite: boolean
  run: (args: Record<string, unknown>, ctx: ToolCtx) => Promise<unknown>
}

type ToolCtx = { arcadia: ArcadiaClient }

const TOOLS: ToolDef[] = [
  {
    name: "list_tenants",
    description:
      "List every tenant on this arcadia deployment. Returns id, slug, name, status, plan, inserted_at. Call this for any question about tenant counts, statuses, or which tenants exist.",
    parameters: {
      type: "object",
      properties: {},
      additionalProperties: false,
    },
    isWrite: false,
    run: async (_args, { arcadia }) => {
      const tenants = await listTenants(arcadia)
      return tenants.map(summarize)
    },
  },
  {
    name: "get_tenant",
    description:
      "Fetch a single tenant by slug (preferred) or id. Returns the tenant summary or null if not found.",
    parameters: {
      type: "object",
      properties: {
        slug: { type: "string", description: "The tenant's slug (e.g. 'acme', 'platform-admin')." },
        id: { type: "string", description: "The tenant's UUID. Use only when the slug is unknown." },
      },
      additionalProperties: false,
    },
    isWrite: false,
    run: async (args, { arcadia }) => {
      const slug = typeof args.slug === "string" ? args.slug : null
      const id = typeof args.id === "string" ? args.id : null
      if (!slug && !id) throw new Error("get_tenant requires { slug } or { id }")
      if (id) {
        try {
          return summarize(await getTenant(arcadia, id))
        } catch {
          return null
        }
      }
      const tenants = await listTenants(arcadia)
      const found = tenants.find((t) => t.slug === slug)
      return found ? summarize(found) : null
    },
  },
]

/** OpenAI-format tool list to pass into ChatRequest.tools. */
export function getOpenAITools(): Tool[] {
  return TOOLS.map((t) => ({
    name: t.name,
    description: t.description,
    parameters: t.parameters,
  }))
}

function summarize(t: Tenant) {
  return {
    id: t.id,
    slug: t.slug,
    name: t.name,
    status: t.status,
    plan: t.plan?.name ?? null,
    inserted_at: t.inserted_at,
  }
}

const TOOL_BY_NAME = new Map(TOOLS.map((t) => [t.name, t]))

function safeJson(value: unknown): string {
  try {
    const text = JSON.stringify(value, null, 2)
    if (text.length > 6000) return text.slice(0, 6000) + "\n…(truncated)"
    return text
  } catch {
    return "(unserializable)"
  }
}

/** Run a list of provider-native tool calls and return `tool` role messages
 *  ready to push back into useChat history. */
export async function runLLMToolCalls(
  calls: LLMToolCall[],
  ctx: ToolCtx,
  opts: { allowWrites?: boolean } = {},
): Promise<{
  results: ToolResult[]
  toolMessages: { role: "tool"; content: string; toolCallId: string; name: string }[]
}> {
  const results: ToolResult[] = []
  const toolMessages: { role: "tool"; content: string; toolCallId: string; name: string }[] = []
  for (const call of calls) {
    const def = TOOL_BY_NAME.get(call.name)
    let parsed: Record<string, unknown> = {}
    try {
      parsed = call.arguments ? (JSON.parse(call.arguments) as Record<string, unknown>) : {}
    } catch {
      const err = `Could not parse arguments JSON: ${call.arguments}`
      results.push({ name: call.name, args: {}, ok: false, error: err })
      toolMessages.push({ role: "tool", content: JSON.stringify({ error: err }), toolCallId: call.id, name: call.name })
      continue
    }
    if (!def) {
      const err = `Unknown tool: ${call.name}`
      results.push({ name: call.name, args: parsed, ok: false, error: err })
      toolMessages.push({ role: "tool", content: JSON.stringify({ error: err }), toolCallId: call.id, name: call.name })
      continue
    }
    if (def.isWrite && !opts.allowWrites) {
      const err = "Write tools require user confirmation."
      results.push({ name: call.name, args: parsed, ok: false, error: err })
      toolMessages.push({ role: "tool", content: JSON.stringify({ error: err }), toolCallId: call.id, name: call.name })
      continue
    }
    try {
      const data = await def.run(parsed, ctx)
      results.push({ name: call.name, args: parsed, ok: true, data })
      toolMessages.push({ role: "tool", content: safeJson(data), toolCallId: call.id, name: call.name })
    } catch (err) {
      const msg = err instanceof Error ? err.message : String(err)
      results.push({ name: call.name, args: parsed, ok: false, error: msg })
      toolMessages.push({ role: "tool", content: JSON.stringify({ error: msg }), toolCallId: call.id, name: call.name })
    }
  }
  return { results, toolMessages }
}