import type { IncomingMessage, ServerResponse } from "node:http";

import { createMoltbotTools } from "../agents/moltbot-tools.js";
import {
  filterToolsByPolicy,
  resolveEffectiveToolPolicy,
  resolveGroupToolPolicy,
  resolveSubagentToolPolicy,
} from "../agents/pi-tools.policy.js";
import {
  buildPluginToolGroups,
  collectExplicitAllowlist,
  expandPolicyWithPluginGroups,
  normalizeToolName,
  resolveToolProfilePolicy,
  stripPluginOnlyAllowlist,
} from "../agents/tool-policy.js";
import { loadConfig } from "../config/config.js";
import { resolveMainSessionKey } from "../config/sessions.js";
import { logWarn } from "../logger.js";
import { getPluginToolMeta } from "../plugins/tools.js";
import { isSubagentSessionKey } from "../routing/session-key.js";
import { normalizeMessageChannel } from "../utils/message-channel.js";

import { authorizeGatewayConnect, type ResolvedGatewayAuth } from "./auth.js";
import { getBearerToken, getHeader } from "./http-utils.js";
import {
  readJsonBodyOrError,
  sendInvalidRequest,
  sendJson,
  sendMethodNotAllowed,
  sendUnauthorized,
} from "./http-common.js";

const DEFAULT_BODY_BYTES = 2 * 1024 * 1024;

type ToolsInvokeBody = {
  tool?: unknown;
  action?: unknown;
  args?: unknown;
  sessionKey?: unknown;
  dryRun?: unknown;
};

function resolveSessionKeyFromBody(body: ToolsInvokeBody): string | undefined {
  if (typeof body.sessionKey === "string" && body.sessionKey.trim()) return body.sessionKey.trim();
  return undefined;
}

function mergeActionIntoArgsIfSupported(params: {
  toolSchema: unknown;
  action: string | undefined;
  args: Record<string, unknown>;
}): Record<string, unknown> {
  const { toolSchema, action, args } = params;
  if (!action) return args;
  if (args.action !== undefined) return args;
  // TypeBox schemas are plain objects; many tools define an `action` property.
  const schemaObj = toolSchema as { properties?: Record<string, unknown> } | null;
  const hasAction = Boolean(
    schemaObj &&
    typeof schemaObj === "object" &&
    schemaObj.properties &&
    "action" in schemaObj.properties,
  );
  if (!hasAction) return args;
  return { ...args, action };
}

export async function handleToolsInvokeHttpRequest(
  req: IncomingMessage,
  res: ServerResponse,
  opts: { auth: ResolvedGatewayAuth; maxBodyBytes?: number; trustedProxies?: string[] },
): Promise<boolean> {
  const url = new URL(req.url ?? "/", `http://${req.headers.host ?? "localhost"}`);
  if (url.pathname !== "/tools/invoke") return false;

  if (req.method !== "POST") {
    sendMethodNotAllowed(res, "POST");
    return true;
  }

  const cfg = loadConfig();
  const token = getBearerToken(req);
  const authResult = await authorizeGatewayConnect({
    auth: opts.auth,
    connectAuth: token ? { token, password: token } : null,
    req,
    trustedProxies: opts.trustedProxies ?? cfg.gateway?.trustedProxies,
  });
  if (!authResult.ok) {
    sendUnauthorized(res);
    return true;
  }

  const bodyUnknown = await readJsonBodyOrError(req, res, opts.maxBodyBytes ?? DEFAULT_BODY_BYTES);
  if (bodyUnknown === undefined) return true;
  const body = (bodyUnknown ?? {}) as ToolsInvokeBody;

  const toolName = typeof body.tool === "string" ? body.tool.trim() : "";
  if (!toolName) {
    sendInvalidRequest(res, "tools.invoke requires body.tool");
    return true;
  }

  const action = typeof body.action === "string" ? body.action.trim() : undefined;

  const argsRaw = body.args;
  const args = (
    argsRaw && typeof argsRaw === "object" && !Array.isArray(argsRaw)
      ? (argsRaw as Record<string, unknown>)
      : {}
  ) as Record<string, unknown>;

  const rawSessionKey = resolveSessionKeyFromBody(body);
  const sessionKey =
    !rawSessionKey || rawSessionKey === "main" ? resolveMainSessionKey(cfg) : rawSessionKey;

  // Resolve message channel/account hints (optional headers) for policy inheritance.
  const messageChannel = normalizeMessageChannel(getHeader(req, "x-moltbot-message-channel") ?? "");
  const accountId = getHeader(req, "x-moltbot-account-id")?.trim() || undefined;

  const {
    agentId,
    globalPolicy,
    globalProviderPolicy,
    agentPolicy,
    agentProviderPolicy,
    profile,
    providerProfile,
    profileAlsoAllow,
    providerProfileAlsoAllow,
  } = resolveEffectiveToolPolicy({ config: cfg, sessionKey });
  const profilePolicy = resolveToolProfilePolicy(profile);
  const providerProfilePolicy = resolveToolProfilePolicy(providerProfile);

  const mergeAlsoAllow = (policy: typeof profilePolicy, alsoAllow?: string[]) => {
    if (!policy?.allow || !Array.isArray(alsoAllow) || alsoAllow.length === 0) return policy;
    return { ...policy, allow: Array.from(new Set([...policy.allow, ...alsoAllow])) };
  };

  const profilePolicyWithAlsoAllow = mergeAlsoAllow(profilePolicy, profileAlsoAllow);
  const providerProfilePolicyWithAlsoAllow = mergeAlsoAllow(
    providerProfilePolicy,
    providerProfileAlsoAllow,
  );
  const groupPolicy = resolveGroupToolPolicy({
    config: cfg,
    sessionKey,
    messageProvider: messageChannel ?? undefined,
    accountId: accountId ?? null,
  });
  const subagentPolicy = isSubagentSessionKey(sessionKey)
    ? resolveSubagentToolPolicy(cfg)
    : undefined;

  // Build tool list (core + plugin tools).
  const allTools = createMoltbotTools({
    agentSessionKey: sessionKey,
    agentChannel: messageChannel ?? undefined,
    agentAccountId: accountId,
    config: cfg,
    pluginToolAllowlist: collectExplicitAllowlist([
      profilePolicy,
      providerProfilePolicy,
      globalPolicy,
      globalProviderPolicy,
      agentPolicy,
      agentProviderPolicy,
      groupPolicy,
      subagentPolicy,
    ]),
  });

  const coreToolNames = new Set(
    allTools
      .filter((tool) => !getPluginToolMeta(tool as any))
      .map((tool) => normalizeToolName(tool.name))
      .filter(Boolean),
  );
  const pluginGroups = buildPluginToolGroups({
    tools: allTools,
    toolMeta: (tool) => getPluginToolMeta(tool as any),
  });
  const resolvePolicy = (policy: typeof profilePolicy, label: string) => {
    const resolved = stripPluginOnlyAllowlist(policy, pluginGroups, coreToolNames);
    if (resolved.unknownAllowlist.length > 0) {
      const entries = resolved.unknownAllowlist.join(", ");
      const suffix = resolved.strippedAllowlist
        ? "Ignoring allowlist so core tools remain available. Use tools.alsoAllow for additive plugin tool enablement."
        : "These entries won't match any tool unless the plugin is enabled.";
      logWarn(`tools: ${label} allowlist contains unknown entries (${entries}). ${suffix}`);
    }
    return expandPolicyWithPluginGroups(resolved.policy, pluginGroups);
  };
  const profilePolicyExpanded = resolvePolicy(
    profilePolicyWithAlsoAllow,
    profile ? `tools.profile (${profile})` : "tools.profile",
  );
  const providerProfileExpanded = resolvePolicy(
    providerProfilePolicyWithAlsoAllow,
    providerProfile ? `tools.byProvider.profile (${providerProfile})` : "tools.byProvider.profile",
  );
  const globalPolicyExpanded = resolvePolicy(globalPolicy, "tools.allow");
  const globalProviderExpanded = resolvePolicy(globalProviderPolicy, "tools.byProvider.allow");
  const agentPolicyExpanded = resolvePolicy(
    agentPolicy,
    agentId ? `agents.${agentId}.tools.allow` : "agent tools.allow",
  );
  const agentProviderExpanded = resolvePolicy(
    agentProviderPolicy,
    agentId ? `agents.${agentId}.tools.byProvider.allow` : "agent tools.byProvider.allow",
  );
  const groupPolicyExpanded = resolvePolicy(groupPolicy, "group tools.allow");
  const subagentPolicyExpanded = expandPolicyWithPluginGroups(subagentPolicy, pluginGroups);

  const toolsFiltered = profilePolicyExpanded
    ? filterToolsByPolicy(allTools, profilePolicyExpanded)
    : allTools;
  const providerProfileFiltered = providerProfileExpanded
    ? filterToolsByPolicy(toolsFiltered, providerProfileExpanded)
    : toolsFiltered;
  const globalFiltered = globalPolicyExpanded
    ? filterToolsByPolicy(providerProfileFiltered, globalPolicyExpanded)
    : providerProfileFiltered;
  const globalProviderFiltered = globalProviderExpanded
    ? filterToolsByPolicy(globalFiltered, globalProviderExpanded)
    : globalFiltered;
  const agentFiltered = agentPolicyExpanded
    ? filterToolsByPolicy(globalProviderFiltered, agentPolicyExpanded)
    : globalProviderFiltered;
  const agentProviderFiltered = agentProviderExpanded
    ? filterToolsByPolicy(agentFiltered, agentProviderExpanded)
    : agentFiltered;
  const groupFiltered = groupPolicyExpanded
    ? filterToolsByPolicy(agentProviderFiltered, groupPolicyExpanded)
    : agentProviderFiltered;
  const subagentFiltered = subagentPolicyExpanded
    ? filterToolsByPolicy(groupFiltered, subagentPolicyExpanded)
    : groupFiltered;

  const tool = subagentFiltered.find((t) => t.name === toolName);
  if (!tool) {
    sendJson(res, 404, {
      ok: false,
      error: { type: "not_found", message: `Tool not available: ${toolName}` },
    });
    return true;
  }

  try {
    const toolArgs = mergeActionIntoArgsIfSupported({
      toolSchema: (tool as any).parameters,
      action,
      args,
    });
    const result = await (tool as any).execute?.(`http-${Date.now()}`, toolArgs);
    sendJson(res, 200, { ok: true, result });
  } catch (err) {
    sendJson(res, 400, {
      ok: false,
      error: { type: "tool_error", message: err instanceof Error ? err.message : String(err) },
    });
  }

  return true;
}
