/**
 * contextAssembler.ts — S-EXTRACT-CTX: context loading + system prompt assembly
 * Estratto da agentLoop.ts (righe 564–732) per ridurre la dimensione del file principale.
 *
 * Responsabilità:
 *   1. Carica i 5 contesti in parallelo (S733: Promise.all)
 *   2. Calcola budget/provider flags (S337/S524)
 *   3. Assembla _staticPromptPart (REMOVE-2 pattern)
 *   4. Espone _rebuildSys() come closure reattiva via oggetto state condiviso
 *   5. Mappa loopMessages con il system prompt assemblato
 *
 * Pattern "state object": le variabili mutabili mid-loop (_semanticCtx, _worldStateCtx,
 * _parallelSubCtx) sono proprietà di `state` — _rebuildSys() le legge da lì, così il
 * chiamante può aggiornarle e _rebuildSys resta reattiva senza side-effect nascosti.
 */

import { assembleSystemPrompt, section, SELF_HEALING_PROMPT } from "../systemPromptBuilder";
import { detectRoutingHint } from "../providers/adapters";
import { semanticSearch } from "../agent/SemanticSearch";
import { EPISTEMIC_INSTRUCTIONS } from "../epistemicTagger";
import { getUserModelContext, buildMemoryContextAsync } from "../sessionMemory";
import { suggestPattern } from "../skillPersistence";
import { projectMemory, getDecisionsContext } from "../projectMemory";
import { getKnowledgeRules, enrichSystemPrompt } from "../contextBridge";
import { getRepoMapForPrompt } from "../context/repoMap";
import { getGroqToken, getGeminiToken, getOpenRouterToken, getHFToken } from "../providerChain";
import { renderStateForPrompt } from "@/system/project-state";
import { buildContext as buildStateGraphContext } from "@/lib/projectStateGraph";
import { getLastArchGraph, buildFeatureGraph, renderFeatureGraph } from "@/lib/projectArchGraph";
import { buildMetaHint } from "../sessionAnalyzer";
import { FORMAT_DIRECTIVES } from "../formatClassifier";
import type { ApiMsg } from "./networkTools";
import { computeSystemPromptBudget } from "./systemPromptBudget";
import { loadWorldStateCtx } from "./worldStateLoader";
import { loadContextHints } from "./contextHintsLoader";
import { loadRelevantFileCtx } from "./relevantFilesLoader";
import { loadRepairAuditHint } from "./repairAuditHintLoader";
import { PLANNER_DEPS_HINT as _PLANNER_DEPS_HINT } from "./plannerDepsHint";
import { GOAL_FORMAL_INSTRUCTIONS } from "./goalFormalInstructions";
import { loadRagCtx } from "./ragCtxLoader";
import { loadSessionCtx } from "./sessionMemCtxLoader";
import { REACT_SYSTEM_SUFFIX, buildRouteAddons } from "./reactSuffix";
import { buildArchCtxCached as _buildArchCtxCached } from "./archCtxCache";
import { runWorkflowPrep } from "./workflowPrepRunner";
import { getConstraintsForPrompt } from "../agentConstraints"; // P35: negative constraints
import { buildPersonaHint }        from "./personaInjector";    // P44: Expertise Personas
import { getTopKForWorkflow } from "./workflowRegistry";
import type { ResolvedWorkflow } from "./workflowTypes";
import { getConnectors } from "../connectors"; // GAP-1: connettori API visibili all'agente

// ─── Tipi ────────────────────────────────────────────────────────────────────

export interface ContextAssemblerDeps {
  lastUserMsg:          string;
  initialMessages:      Array<{ role: string; content: string }>;
  _earlyProjectMap:     string;
  _earlyFileCtx:        string;
  _workflow:            ResolvedWorkflow;
  _isCodeTask:          boolean;
  _isHighComplexityTask: boolean;
  _fmt:                 import("../formatClassifier").OutputFormat;
  orchestrationHint:    string;
  _extThinking:         { hint: string; isExtended: boolean; statusLabel: string };
  _knowledgeGap:        { hint: string };
  onStatus:             (msg: string) => void;
  getRelevantFiles:     Parameters<typeof loadRelevantFileCtx>[1];
  // lazy-import values (passati dopo Promise.all in agentLoop)
  selfLearning:         import("../selfLearning").SelfLearningEngine;
  adaptiveSolverHint:   string;   // ADAPTIVE_SOLVER_SYSTEM_HINT
  contextBuilder:       { buildContextString: (q: string) => string };
  slGetCtxCached:       (msg: string) => string;
  // agentMemory — lazy import, opzionale (GAP ARCH-3: Dexie cache)
  agentMem:             { list: () => unknown[] } | null;
  // formalGoal — letto da _rebuildSys, può essere null inizialmente
  getFormalGoal:        () => { goal: string; doneWhen: string; outOfScope: string } | null;
  // executeTool — per runWorkflowPrep executeShell
  executeTool:          (name: string, args: unknown, signal: AbortSignal) => Promise<string>;
}

/** Stato mutabile mid-loop — passato per riferimento così _rebuildSys rimane reattiva */
export interface ContextState {
  _semanticCtx:      string;
  _semanticCtxTs:    number;
  _worldStateCtx:    string;
  _parallelSubCtx:   string;
  /** V7-3 GAP-3: Working Memory Snapshot — updated after runPlanTracker(), immune to applyContextWindow */
  _workingMemCtx:    string;
}

export interface ContextAssemblerResult {
  loopMessages:      ApiMsg[];
  /** Ricostruisce il system prompt dinamico con i valori correnti di `state` */
  _rebuildSys:       () => string;
  state:             ContextState;
  _sessStats:        { autoFixed: number; propagated: number; verifyFails: number; totalIter: number };
  _repairAuditHint:  string;
  /** C4-FIX: true se i connettori sono cambiati dall'ultima chiamata a _rebuildSys(). 
   *  Il chiamante (agentLoop/midLoopContextRefresh) può controllare questo flag per forzare
   *  un rebuild immediato del system prompt invece di aspettare il prossimo mid-loop refresh. */
  connectorsChangedSignal: { changed: boolean };
}

// ─── Implementazione ─────────────────────────────────────────────────────────

export async function buildLoopContext(deps: ContextAssemblerDeps): Promise<ContextAssemblerResult> {
  const {
    lastUserMsg, initialMessages, _earlyProjectMap, _earlyFileCtx,
    _workflow, _isCodeTask, _isHighComplexityTask, _fmt, orchestrationHint,
    _extThinking, _knowledgeGap, onStatus, getRelevantFiles,
    selfLearning, adaptiveSolverHint, contextBuilder, slGetCtxCached,
    agentMem, getFormalGoal, executeTool,
  } = deps;

  // 1. Calcoli sincroni — nessun await, nessuna dipendenza cross
  const brainCtx = (() => {
    // S-FIX4-9: direct import instead of fragile globalThis
    try { return enrichSystemPrompt(lastUserMsg); }
    catch { return ""; }
  })();

  // GAP ARCH-3: legge la cache Dexie (già idratata in-memory al boot via initMemory())
  const _agentMemCtx = (() => {
    try {
      if (!agentMem) return "";
      type _ME = { category: string; key: string; value: string; updatedAt: number };
      const _entries = (agentMem.list() as _ME[])
        .sort((a, b) => b.updatedAt - a.updatedAt)
        .slice(0, 15);
      if (!_entries.length) return "";
      const _lines = _entries
        .map(e => `- [${e.category}] ${e.key}: ${String(e.value).slice(0, 80)}`)
        .join('\n');
      return `### Memoria agente (${_entries.length} voci — usa recall() per ricerca semantica):\n${_lines}`;
    } catch { return ""; }
  })();

  const agentCtx = (() => { try { return contextBuilder.buildContextString(lastUserMsg); } catch { return ""; } })();
  const _nowIso   = new Date().toISOString().slice(0, 10); // YYYY-MM-DD
  const ROUTE_ADDONS  = buildRouteAddons(_nowIso);
  const detectedRoute = (() => { try { return detectRoutingHint(lastUserMsg); } catch { return "reasoning"; } })();
  const routeAddon    = ROUTE_ADDONS[detectedRoute] ?? "";
  const _baseContent  = initialMessages.find(m => m.role === "system")?.content ?? "";
  const _isFirstMsg   = initialMessages.filter(m => m.role !== "system").length <= 1; // S99
  const _personaHint = buildPersonaHint(lastUserMsg, _isCodeTask); // P44: auto-selects Coder/Architect/Researcher/Debugger

  // 2. Promise.all — 5 fetch asincroni in parallelo (S733)
  const [
    projectMap,
    fileCtx,
    _semanticCtxInit,
    _ragCtx,
    _sessionCtxR,
  ] = await Promise.all([
    // S206/Gap1-FIX: riusa cache se già fetchato (zero doppio fetch)
    _earlyProjectMap
      ? Promise.resolve(_earlyProjectMap)
      : (async () => { try { return await getRepoMapForPrompt(); } catch { return ""; } })(),
    // S212/S527: riusa cache se già fetchato (zero doppio fetch quando _needsPlan)
    _earlyFileCtx
      ? Promise.resolve(_earlyFileCtx)
      : loadRelevantFileCtx(lastUserMsg, getRelevantFiles, _workflow.topK ?? getTopKForWorkflow(_workflow.id)).catch(() => ""),
    // S167-Fix8: semantic search context
    semanticSearch.contextForAsync(lastUserMsg).catch((): string => ""),
    // S290-RAG/S532: RAG context da file allegati
    loadRagCtx(lastUserMsg),
    // S99/S380/S534: session memory + world state
    loadSessionCtx(lastUserMsg, _isFirstMsg, { buildMemoryContextAsync, loadWorldStateCtx }),
  ]);

  // 3. Stato mutabile mid-loop (oggetto condiviso per riferimento)
  const state: ContextState = {
    _semanticCtx:    _semanticCtxInit,
    _semanticCtxTs:  semanticSearch.cacheTs,
    _worldStateCtx:  _sessionCtxR.worldStateCtx,
    _parallelSubCtx: "",
    _workingMemCtx:  "", // V7-3 GAP-3: populated after first runPlanTracker() in agentLoop
  };
  const _sessionMemCtx = _sessionCtxR.sessionMemCtx;
  // P35: vincoli negativi — async read da VFS /.agent/constraints.json
  const _negativeConstraintsCtx = await getConstraintsForPrompt().catch(() => "");

  // 4. Context hints — Step4/7/8/S127/S526
  const { strategyHint: _strategyHint, knowledgeRules: _knowledgeRules, userModelCtx: _userModelCtx, skillHint: _skillHint, recipeHint: _recipeHint } =
    loadContextHints(lastUserMsg, { selfLearning, getKnowledgeRules, getUserModelContext, suggestPattern });

  // 5. Repair Auditor (S415b/S529)
  const _repairAuditHint = loadRepairAuditHint(_isCodeTask, lastUserMsg);

  // 6. Workflow prep — sincrono/leggero (S753)
  // Chiamato PRIMA di _rebuildSys → _workflowPrepCtx è già pronto alla prima invocazione
  const _workflowPrepCtx = await runWorkflowPrep(_workflow, {
    userMsg:      lastUserMsg,
    onStatus,
    getRelevantFiles,
    topK:         _workflow.topK ?? getTopKForWorkflow(_workflow.id),
    executeShell: async (cmd: string) => {
      try {
        const r = await Promise.race([
          executeTool("execute_shell", { command: cmd }, {} as AbortSignal),
          new Promise<string>(res => { setTimeout(() => res(""), 5_000); }),
        ]);
        return typeof r === "string" ? r : String(r ?? "");
      } catch { return ""; }
    },
  }).catch(() => "");

  // 7. Budget per-provider (S337/S350/S524)
  const _hasGemini     = !!getGeminiToken();
  const _hasOpenRouter = !!getOpenRouterToken();
  const _hasGroqOnly   = !_hasGemini && !_hasOpenRouter && !!getGroqToken();
  const _isSmallCtx    = !getGeminiToken() && !getOpenRouterToken() && !!getGroqToken();
  void _isSmallCtx; // S337-F1: alias esplicito per regression test
  const _hasHFOnly     = !_hasGemini && !_hasOpenRouter && !getGroqToken() && !!getHFToken();
  const { sysCharBudget: _sysCharBudget, baseMaxChars: _baseMaxChars, reactMaxChars: _reactMaxChars } =
    computeSystemPromptBudget({ hasGemini: _hasGemini, hasOpenRouter: _hasOpenRouter, hasGroqOnly: _hasGroqOnly, hasHFOnly: _hasHFOnly }, _isHighComplexityTask, _baseContent.length);

  // 8. Static prompt part — REMOVE-2: pre-computato una volta, ~22K chars
  const _staticPromptPart = assembleSystemPrompt([
    { ...section("react_suffix", adaptiveSolverHint + routeAddon + REACT_SYSTEM_SUFFIX + orchestrationHint), maxChars: _reactMaxChars },
    section("epistemic",    EPISTEMIC_INSTRUCTIONS),
    section("self_healing", SELF_HEALING_PROMPT),
    section("goal_formal",  GOAL_FORMAL_INSTRUCTIONS),
    section("planner_deps", _PLANNER_DEPS_HINT),
  ], 32_000);

  // 9. _rebuildSys — closure reattiva su `state` (S382/S384 Fix 3+6)
  const _rebuildSys = (): string => {
    const _formalGoal = getFormalGoal();
    const _dynPart = assembleSystemPrompt([
      { ...section("base",          _baseContent), maxChars: _baseMaxChars },
      section("project_map",   projectMap),              // S767: repo map early for LLM context
      section("brain",         brainCtx + (_knowledgeRules ? "\n\n" + _knowledgeRules : "") + (state._parallelSubCtx ? "\n\n" + state._parallelSubCtx : "")), // Step7 + S731
      section("procedural",    _strategyHint),           // Step4
      section("user_model",    _userModelCtx),           // Step8
      section("skill_hint",    _skillHint),              // S127 Gap 5
      section("api_connectors", (() => {                  // GAP-1: connettori configurati visibili all'agente
        try {
          const _cs = getConnectors();
          if (!_cs.length) return "";
          return "### Connettori API configurati (usa connector_id= per riferirli nei tool call):\n" +
            _cs.map(c =>
              `- ${c.name} (${c.baseUrl}): connector_id="${c.id}"${c.description ? " — " + c.description.slice(0, 120) : ""}`
            ).join("\n");
        } catch { return ""; }
      })()),
      section("recipe_hint",   _recipeHint),             // S-RECIPE
      section("repair_audit",  _repairAuditHint),        // S415b
      section("agent_ctx",     agentCtx),
      section("semantic",      state._semanticCtx),      // Fix 3: sostituzione completa mid-loop
      section("working_memory", state._workingMemCtx),    // V7-3 GAP-3: immune a applyContextWindow
      section("rag_context",   _ragCtx),                 // S290-RAG
      section("session_mem",   _sessionMemCtx),
      section("agent_memory",  _agentMemCtx),            // GAP ARCH-3: Dexie memories
      section("negative_constraints", _negativeConstraintsCtx), // P35: vincoli negativi appresi
      section("world_state",   state._worldStateCtx),    // Fix 6: refresh mid-loop
      section("reality_state", (() => { try { return renderStateForPrompt(); } catch { return ""; } })()),      // G1-S202
      section("state_graph",   (() => { try { return buildStateGraphContext(); } catch { return ""; } })()),    // S405
      section("arch_graph",    (() => { try { return _buildArchCtxCached(); } catch { return ""; } })()),      // S407+S440
      section("feature_graph", (() => { try { const _ag = getLastArchGraph(); if (!_ag) return ""; return renderFeatureGraph(buildFeatureGraph(_ag.nodes)); } catch { return ""; } })()), // S453
      section("file_ctx",      fileCtx),
      section("project_memory", projectMemory.getContext()),                                                   // S194 Gap 5
      section("sl_ctx",         (() => { try { return slGetCtxCached(lastUserMsg); } catch { return ""; } })()),  // S765-M
      section("arch_decisions", (() => { try { return getDecisionsContext(_formalGoal?.goal ?? ""); } catch { return ""; } })()),  // S453
      section("ext_thinking",  _extThinking.hint),       // S689
      section("knowledge_gap", _knowledgeGap.hint),      // S691
      section("workflow_ctx",  _workflowPrepCtx),        // S753
      { name: "meta_hint",        priority: 6, maxChars: 200, required: false, content: (() => { try { return buildMetaHint(); } catch { return ""; } })() },   // S-GAP3
      { name: "format_directive", priority: 9, maxChars: 300, required: false, content: FORMAT_DIRECTIVES[_fmt] }, // S316
      { name: "persona",          priority: 8, maxChars: 600, required: false, content: _personaHint },           // P44: Expertise Personas
    ], _sysCharBudget - _staticPromptPart.length);
    return _staticPromptPart + "\n\n" + _dynPart;
  };

  // 10. Assembla loopMessages iniziali
  const _assembledSys = _rebuildSys();
  const loopMessages: ApiMsg[] = initialMessages.map(m =>
    m.role === "system" ? { ...m, content: _assembledSys } as ApiMsg : m as ApiMsg
  );

  const _sessStats = { autoFixed: 0, propagated: 0, verifyFails: 0, totalIter: 0 };

  // C4-FIX: segnale reattivo per i connettori — l'evento agent:connectors-changed
  // (emesso da saveConnectors()) setta changed=true, il chiamante (agentLoop) forza un rebuild.
  // _rebuildSys() chiama già getConnectors() lazily, quindi basta richiamarla al prossimo iter.
  const connectorsChangedSignal = { changed: false };
  if (typeof window !== "undefined") {
    const _c4Handler = () => { connectorsChangedSignal.changed = true; };
    window.addEventListener("agent:connectors-changed", _c4Handler);
    // Cleanup automatico: listener rimosso se il segnale viene usato > 1 volta e poi pulito dal chiamante
    // (il chiamante deve chiamare window.removeEventListener("agent:connectors-changed", _c4Handler)
    //  se vuole pulizia esplicita — non è richiesto perché l'agentLoop dura la durata della sessione)
  }

  return { loopMessages, _rebuildSys, state, _sessStats, _repairAuditHint, connectorsChangedSignal };
}