db

Mix.install([
  {:jason, "~> 1.4"},
  {:kino, "~> 0.10.0"}
])

Section

defmodule Ecto2 do
  def insert(db, v) do
    db = db ++ [v]
  end

  def update(db, v) do
    i =
      Enum.filter_map(
        Enum.with_index(db),
        fn {x, _} ->
          x.id == v.id
        end,
        fn {_, i} ->
          i
        end
      )
      |> Enum.at(0)

    db = List.replace_at(db, i, v)
  end

  def delete(db, v) do
    db = List.delete(db, v)
  end

  def print(db) do
    Enum.map(db, fn x ->
      [x.id, x.name]
    end)
    |> IO.inspect()
  end

  def load(db) do
    File.read!("db.json")
    |> Jason.decode!(keys: :atoms)
  end

  def save(db) do
    json = Jason.encode!(db)
    File.write!("db.json", json)
  end
end

now =
  NaiveDateTime.utc_now()
  |> NaiveDateTime.truncate(:second)

db = [
  %{
    id: 1,
    name: "ryu",
    age: 10,
    gaku: "s",
    inserted_at: ~N[2023-10-31 05:35:23],
    updated_at: ~N[2023-11-30 05:35:37]
  },
  %{
    id: 2,
    name: "ryo",
    age: 20,
    gaku: "s",
    inserted_at: ~N[2023-10-31 05:35:23],
    updated_at: ~N[2023-11-30 05:35:37]
  },
  %{
    id: 3,
    name: "alice",
    age: 20,
    gaku: "s",
    inserted_at: ~N[2023-10-31 05:35:23],
    updated_at: ~N[2023-11-30 05:35:37]
  },
  %{
    id: 4,
    name: "kent",
    age: 30,
    gaku: "s",
    inserted_at: ~N[2023-10-31 05:35:23],
    updated_at: ~N[2023-11-30 05:35:37]
  }
]

# Ecto2.save(db)
db = Ecto2.load(db)
# Kino.DataTable.new(db)

Ecto2.print(db)

db =
  Ecto2.insert(db, %{
    id: 5,
    name: "kent",
    age: 30,
    gaku: "s",
    inserted_at: now,
    updated_at: now
  })

Ecto2.print(db)

Kino.DataTable.new(db)

db =
  Ecto2.delete(db, %{
    id: 5,
    name: "kent",
    age: 30,
    gaku: "s",
    inserted_at: now,
    updated_at: now
  })

Ecto2.print(db)
Kino.DataTable.new(db)

db =
  Ecto2.update(db, %{
    id: 1,
    name: "yoko",
    age: 30,
    gaku: "s",
    inserted_at: now,
    updated_at: now
  })

Ecto2.print(db)
Kino.DataTable.new(db)