Ad some CRUD methods to manage units table

com/Unit/Create.lua

@@ -0,0 +1,77 @@
+-- File com/Unit/Create.lua
+--
+-- Created at 2025-05-10 18:23
+--
+-- Updated at - 
+-- Description:
+--- Creates a record in the unit.db database without 
+--- requiring additional permissions. Requires username, 
+--- password (hashing occurs at the server level), and email fields.
+
+local log = require("internal.log")
+local db = require("internal.database.sqlite").connect("db/unit.db", {log = true})
+local session = require("internal.session")
+local crypt = require("internal.crypt.bcrypt")
+local sha256 = require("internal.crypt.sha256")
+
+local common = require("com/Unit/_common")
+
+-- Preparing for first db query
+local function close_db()
+  if db then
+    log.debug("Closing DB connection")
+    db:close()
+    db = nil
+  end
+end
+
+local params = session.request.params.get()
+
+local ok, mp = common.CheckMissingElement({"username", "password", "email"}, params)
+if not ok then
+  close_db()
+  session.response.send_error(-32602, "Missing params", mp)
+end
+
+local hashPass = crypt.generate(params.password, crypt.DefaultCost)
+local unitID = string.sub(sha256.hash(session.__seed), 1, 16)
+
+-- First db query: check if username or email already exists
+local existing, err = db:query("SELECT 1 FROM units WHERE email = ? OR username = ? LIMIT 1", {
+  params.email,
+  params.username
+})
+
+if err ~= nil then
+  log.error("Email check failed: "..tostring(err))
+  return session.response.send_error()
+end
+
+if existing and #existing > 0 then
+  return session.response.send_error(-32101, "Unit already exists")
+end
+
+-- Second db query: insert new unit
+local ctx, err = db:exec(
+  "INSERT INTO units (user_id, username, email, password) VALUES (?, ?, ?, ?)",
+  {
+    unitID,
+    params.username,
+    params.email,
+    hashPass,
+  }
+)
+if err ~= nil then
+  log.error("Insert failed: "..tostring(err))
+  return session.response.send_error()
+end
+
+local res, err = ctx:wait()
+if err ~= nil then
+  log.error("Insert confirmation failed: "..tostring(err))
+  return session.response.send_error()
+end
+
+session.response.send({message = "Unit created successfully", unit_id = unitID})
+
+close_db()