// lib/activePointer.js
// Active-pointer write: persist -> re-register -> propagate -> refresh assets (ARCHITECTURE.md 5.5)
const Plugin   = require("@saltcorn/data/models/plugin");
const { getState } = require("@saltcorn/data/db/state");
const db       = require("@saltcorn/data/db");
const { PLUGIN_NAME } = require("./constants");

// Resolve the install-name row defensively: _sc_plugins.name is the INSTALL name, which
// is NOT guaranteed to equal plugin_name. Try the canonical name, then fall back to scanning
// for the row whose module resolves to plugin_name. (folded review fix: read/write name-space split)
async function findPluginRow() {
  let p = await Plugin.findOne({ name: PLUGIN_NAME });
  if (p) return p;
  const all = await Plugin.find({});
  return all.find((r) => {
    const mod = getState().plugins[PLUGIN_NAME];
    return mod && (getState().plugin_module_names[r.name] === PLUGIN_NAME || r.name === PLUGIN_NAME);
  }) || null;
}


async function setActivePointer(patch /* {activeThemeId?|activeByRole?|activeHash?} */) {
  const plugin = await findPluginRow();
  if (!plugin) throw new Error("theme-builder plugin row not found");
  plugin.configuration = { ...(plugin.configuration || {}), ...patch };
  await plugin.upsert();                                   // _sc_plugins (plugin.ts:104-119)
  await Plugin.loadPlugin(plugin);                          // re-register -> re-run headers(cfg)
  await getState().refresh_views();                        // REBUILD assets_by_role (Fix 1)
  getState().processSend({ refresh_plugin_cfg: PLUGIN_NAME, tenant: db.getTenantSchema() });
  return plugin.configuration;
}


// READ: live merged cfg, no DB hit.
function getActivePointer() {
  const cfg = getState().plugin_cfgs[PLUGIN_NAME] || {};
  return { activeThemeId: cfg.activeThemeId || null, activeByRole: cfg.activeByRole || {},
           activeHash: cfg.activeHash || "0" };
}


// Remove every activeByRole entry whose value === id, then persist the scrubbed map.
async function dropRoleRefs(id) {
  const { activeByRole } = getActivePointer();
  const scrubbed = {};
  for (const role of Object.keys(activeByRole)) {
    if (activeByRole[role] !== id) scrubbed[role] = activeByRole[role];
  }
  return setActivePointer({ activeByRole: scrubbed });
}


module.exports = { setActivePointer, getActivePointer, findPluginRow, dropRoleRefs };