/**
 * End-to-end proof: a recall block produced by the REAL injection shape reaches
 * the SYSTEM prompt and does NOT reach any user/message content.
 *
 * Why this file exists next to `loop.test.js`
 * -------------------------------------------
 * `loop.test.js` asserts the pure decision rewrite (`promoteSnapshotSections`).
 * That is necessary but not sufficient: the bug it fixes was that the rewrite
 * never fired on the real injection shape, and a unit test can only catch that
 * if it also encodes the real shape. This file closes the loop the other way —
 * it mounts the actual `HologramAgentLoop` on real dsh services (`SessionStore`,
 * `AgentRegistry`, `LlmRuntime`, `SystemPrompt`, `ToolRuntime`,
 * `SessionProjectionRegistry`), drives one real turn (pre-step → request build →
 * LLM call), and asserts against **the request object the adapter actually
 * received**, not an intermediate decision.
 *
 * Two directions, both required:
 *   E1  positive — the recall text appears in the system prompt the adapter got.
 *   E2  negative — the recall text appears in NO message body the adapter got
 *       (every message, every block; not just the last one).
 *
 * Only E1 fails on the broken commit; E2 is already true there because the old
 * code left recall in history. E2 is what this fix is *for*: it must stay true
 * after the move, otherwise the promotion would duplicate recall rather than
 * relocate it.
 *
 * No network: the "adapter" is a local `LlmAdapter` subclass that records the
 * request and yields one text chunk.
 *
 * @module dsh-memory/test/loop-system-e2e
 */

import assert from 'node:assert/strict'
import { createRequire } from 'node:module'
import { pathToFileURL } from 'node:url'
import test from 'node:test'
import { Context } from '@deepseek-ai/cordis'
import { AgentRegistry } from '@deepseek-ai/dsh-agent'
import { LlmAdapter, LlmRuntime, createUserMessage } from '@deepseek-ai/dsh-llm'
import { SessionStore } from '@deepseek-ai/dsh-session'
import { SystemPrompt } from '@deepseek-ai/dsh-system-prompt'
import { ToolRuntime } from '@deepseek-ai/dsh-tools'
import { HologramAgentLoop } from '../lib/loop.js'

/**
 * Load `SessionProjectionRegistry` the way the harness does.
 *
 * It is a peer of `dsh-agent-loop`, not of this package, so a bare specifier
 * only resolves when the repo's `node_modules` happens to link it. Resolving
 * from `dsh-agent-loop`'s own location is exactly what a real dsh process does;
 * if neither route works there is no harness to run against, and the test skips
 * loudly instead of asserting on a half-mounted app.
 * @returns {Promise<Function|null>}
 */
async function loadProjectionRegistry() {
  try {
    return (await import('@deepseek-ai/dsh-session-projection')).SessionProjectionRegistry
  } catch {
    try {
      const peerRequire = createRequire(import.meta.resolve('@deepseek-ai/dsh-agent-loop'))
      return (await import(pathToFileURL(peerRequire.resolve('@deepseek-ai/dsh-session-projection')).href))
        .SessionProjectionRegistry
    } catch {
      return null
    }
  }
}

/** Every text the model would read out of a message body. */
function bodyText(message) {
  if (!Array.isArray(message?.content)) return ''
  return message.content.map((block) => (typeof block?.text === 'string' ? block.text : '')).join('')
}

/** The system prompt text as the adapter received it. */
function systemText(request) {
  return request.messages
    .filter((message) => message.role === 'system')
    .map((message) => bodyText(message))
    .join('\n')
}

/** Every non-system message body, flattened, for the negative direction. */
function historyBlocks(request) {
  return request.messages
    .filter((message) => message.role !== 'system')
    .map((message, index) => ({ index, role: message.role, kind: message.source?.kind, text: bodyText(message) }))
}

test('E1/E2: recall reaches the system prompt and no message body', async (t) => {
  const SessionProjectionRegistry = await loadProjectionRegistry()
  if (SessionProjectionRegistry === null) {
    t.skip('@deepseek-ai/dsh-session-projection not resolvable from this install (no harness to mount)')
    return
  }

  const RECALL = 'RECALLED-NOTE-4471: user prefers evidence over summaries.'

  /** Records the request it is called with; yields one stop-finish text chunk. */
  const captured = []
  class CaptureAdapter extends LlmAdapter {
    async *stream(request) {
      captured.push(request)
      yield { type: 'block-start', index: 0, blockType: 'text' }
      yield { type: 'text-delta', index: 0, text: 'acknowledged' }
      yield { type: 'block-end', index: 0, block: { type: 'text', text: 'acknowledged' } }
      yield { type: 'finish', reason: 'stop' }
    }
  }

  const ctx = new Context()
  try {
    // Cordis defers service publication by a microtask; each `new` below needs
    // the previous one visible, so yield between mounts.
    new SessionStore(ctx)
    await new Promise((resolve) => setTimeout(resolve, 0))
    new AgentRegistry(ctx)
    new SystemPrompt(ctx, {})
    new ToolRuntime(ctx)
    new LlmRuntime(ctx)
    new SessionProjectionRegistry(ctx)
    await new Promise((resolve) => setTimeout(resolve, 0))

    // The loop under test. Mount before any agent exists: `setFactory` runs in
    // the constructor and the class refuses a second registration.
    new HologramAgentLoop(ctx, { maxParallelToolCalls: 4, agents: [] })
    await new Promise((resolve) => setTimeout(resolve, 0))
    ctx.llm.registerAdapter(['capture'], new CaptureAdapter())

    // The REAL injection shape, reproduced byte for byte from `lib/index.js:932`:
    // one text block whose text IS the section text, `form: 'snapshot'`.
    ctx.on(
      'agent/pre-step',
      async (payload, next) => {
        const decision = await next()
        if (decision.kind === 'reject' || payload.signal.aborted) return decision
        return {
          ...decision,
          messages: [
            ...decision.messages,
            createUserMessage({
              content: [{ type: 'text', text: RECALL }],
              source: { kind: 'memory', form: 'snapshot', sections: [{ name: 'memory', text: RECALL }] },
            }),
          ],
        }
      },
      { prepend: true },
    )

    const handle = await ctx.agents.create({
      sessionId: 'loop-system-e2e',
      agentOptions: { provider: 'capture', model: 'capture-1' },
    })
    const agent = handle.agent
    agent.followup(
      createUserMessage({ content: [{ type: 'text', text: 'what did we decide?' }], source: { kind: 'user' } }),
    )
    await agent.whenIdle()

    assert.equal(captured.length, 1, `the adapter must be called exactly once; got ${captured.length} call(s)`)
    const request = captured[0]

    // ── E1 · positive: the recall is in the system prompt ────────────────
    const system = systemText(request)
    assert.ok(
      system.includes(RECALL),
      `E1: recall must appear in the system prompt the adapter received. system prompt was ${JSON.stringify(system)}`,
    )

    // ── E2 · negative: the recall is in NO message body ──────────────────
    const history = historyBlocks(request)
    const leaking = history.filter((entry) => entry.text.includes(RECALL))
    assert.deepEqual(
      leaking,
      [],
      `E2: recall must not appear in ANY non-system message; leaking messages: ${JSON.stringify(leaking)}`,
    )

    // E2b · the loop must not duplicate it either: exactly one system message
    // may carry it, so a "promote but keep" bug cannot hide behind E1.
    const carriers = request.messages.filter((message) => bodyText(message).includes(RECALL))
    assert.equal(
      carriers.length,
      1,
      `E2b: exactly one message may carry the recall (a move, not a copy); got ${carriers.length}: ${JSON.stringify(
        carriers.map((message) => message.role),
      )}`,
    )
    assert.equal(carriers[0].role, 'system', `E2b: the sole carrier must be the system message; got ${carriers[0].role}`)
  } finally {
    await ctx.fiber.dispose()
  }
})