working on db logic

test/db_helper_test.exs

@@ -0,0 +1,113 @@
+defmodule SQLTest do
+  use ExUnit.Case
+  alias ElixirAi.Data.DbHelpers
+
+  test "converts simple named parameters" do
+    query = "SELECT * FROM users WHERE id = $(id) AND email = $(email)"
+
+    params = %{
+      "id" => 10,
+      "email" => "test@example.com"
+    }
+
+    assert DbHelpers.named_params_to_positional_params(query, params) ==
+             {
+               "SELECT * FROM users WHERE id = $1 AND email = $2",
+               [10, "test@example.com"]
+             }
+  end
+
+  test "reuses positional parameter for repeated named parameter" do
+    query = """
+    SELECT * FROM users
+    WHERE id = $(id)
+    OR owner_id = $(id)
+    """
+
+    params = %{"id" => 42}
+
+    assert DbHelpers.named_params_to_positional_params(query, params) ==
+             {
+               """
+               SELECT * FROM users
+               WHERE id = $1
+               OR owner_id = $1
+               """,
+               [42]
+             }
+  end
+
+  test "assigns parameters in order of first appearance" do
+    query = "SELECT * FROM items WHERE category = $(category) AND owner = $(owner)"
+
+    params = %{
+      "owner" => 5,
+      "category" => "books"
+    }
+
+    assert DbHelpers.named_params_to_positional_params(query, params) ==
+             {
+               "SELECT * FROM items WHERE category = $1 AND owner = $2",
+               ["books", 5]
+             }
+  end
+
+  test "handles multiple distinct parameters" do
+    query = "INSERT INTO posts(title, body, author_id) VALUES($(title), $(body), $(author))"
+
+    params = %{
+      "title" => "Hello",
+      "body" => "World",
+      "author" => 7
+    }
+
+    assert DbHelpers.named_params_to_positional_params(query, params) ==
+             {
+               "INSERT INTO posts(title, body, author_id) VALUES($1, $2, $3)",
+               ["Hello", "World", 7]
+             }
+  end
+
+  test "works when same parameter appears many times" do
+    query = """
+    SELECT *
+    FROM logs
+    WHERE user_id = $(user)
+    OR editor_id = $(user)
+    OR reviewer_id = $(user)
+    """
+
+    params = %{"user" => 99}
+
+    assert DbHelpers.named_params_to_positional_params(query, params) ==
+             {
+               """
+               SELECT *
+               FROM logs
+               WHERE user_id = $1
+               OR editor_id = $1
+               OR reviewer_id = $1
+               """,
+               [99]
+             }
+  end
+
+  test "raises if parameter is missing" do
+    query = "SELECT * FROM users WHERE id = $(id)"
+
+    params = %{}
+
+    assert_raise KeyError, fn ->
+      DbHelpers.named_params_to_positional_params(query, params)
+    end
+  end
+
+  test "query without named parameters returns unchanged query and empty params" do
+    query = "SELECT * FROM users"
+
+    params = %{}
+
+    assert DbHelpers.named_params_to_positional_params(query, params) ==
+             {"SELECT * FROM users", []}
+  end
+end