ruchy 4.2.0

// 12_classes_structs.ruchy - Object-oriented patterns using closures and objects

fn main() {
    println("=== Object-Oriented Patterns ===\n")

    // Object literals for data structures
    println("=== Point Objects ===")

    let p1 = { x: 3.0, y: 4.0 }
    let p2 = { x: 1.0, y: 2.0 }

    println(f"Point 1: ({p1.x}, {p1.y})")
    println(f"Point 2: ({p2.x}, {p2.y})")

    // Factory functions (constructor pattern)
    fn make_point(x, y) {
        { x: x, y: y }
    }

    fn distance_from_origin(point) {
        sqrt(point.x * point.x + point.y * point.y)
    }

    fn distance_between(p1, p2) {
        let dx = p1.x - p2.x
        let dy = p1.y - p2.y
        sqrt(dx * dx + dy * dy)
    }

    let p3 = make_point(5.0, 12.0)
    println(f"Point 3: ({p3.x}, {p3.y})")
    println(f"Distance from origin: {distance_from_origin(p3)}")
    println(f"Distance between p1 and p2: {distance_between(p1, p2)}")

    // Bank Account pattern using functions
    println("\n=== Bank Account Example ===")

    fn deposit(account, amount) {
        if amount > 0 {
            println(f"Deposited ${amount}")
            { owner: account.owner, balance: account.balance + amount }
        } else {
            account
        }
    }

    fn withdraw(account, amount) {
        if amount > 0 && amount <= account.balance {
            println(f"Withdrew ${amount}")
            { owner: account.owner, balance: account.balance - amount }
        } else {
            println("Insufficient funds")
            account
        }
    }

    fn display_account(account) {
        println(f"Account: {account.owner}, Balance: ${account.balance}")
    }

    let account1 = { owner: "Alice", balance: 1000.0 }
    display_account(account1)

    let account2 = deposit(account1, 500.0)
    display_account(account2)

    let account3 = withdraw(account2, 200.0)
    display_account(account3)

    let account4 = withdraw(account3, 2000.0)
    display_account(account4)

    // Composition pattern
    println("\n=== Composition Example ===")

    fn make_employee(name, id, department) {
        { name: name, id: id, department: department }
    }

    fn make_manager(name, id, department, team_size) {
        let emp = make_employee(name, id, department)
        { employee: emp, team_size: team_size }
    }

    fn display_manager(mgr) {
        println(f"Manager: {mgr.employee.name}")
        println(f"ID: {mgr.employee.id}")
        println(f"Department: {mgr.employee.department}")
        println(f"Team size: {mgr.team_size}")
    }

    let manager = make_manager("Bob", 12345, "Engineering", 10)
    display_manager(manager)

    // Container pattern
    println("\n=== Container Example ===")

    fn make_container(value) {
        { value: value }
    }

    fn get_value(container) {
        container.value
    }

    let int_container = make_container(42)
    println(f"Integer container: {get_value(int_container)}")

    let string_container = make_container("Hello")
    println(f"String container: {get_value(string_container)}")

    // Polymorphism via duck typing
    println("\n=== Shape Calculations ===")

    fn make_circle(radius) {
        { kind: "circle", radius: radius }
    }

    fn make_rectangle(width, height) {
        { kind: "rectangle", width: width, height: height }
    }

    fn make_triangle(base, height) {
        { kind: "triangle", base: base, height: height }
    }

    fn area(shape) {
        if shape.kind == "circle" {
            3.14159 * shape.radius * shape.radius
        } else if shape.kind == "rectangle" {
            shape.width * shape.height
        } else {
            0.5 * shape.base * shape.height
        }
    }

    fn describe(shape) {
        if shape.kind == "circle" {
            f"Circle with radius {shape.radius}"
        } else if shape.kind == "rectangle" {
            f"Rectangle {shape.width}x{shape.height}"
        } else {
            f"Triangle with base {shape.base}"
        }
    }

    let shapes = [
        make_circle(5.0),
        make_rectangle(10.0, 20.0),
        make_triangle(6.0, 8.0)
    ]

    for shape in shapes {
        println(f"{describe(shape)}: area = {area(shape)}")
    }

    // Drawable interface via convention
    println("\n=== Drawable Pattern ===")

    fn draw(drawable) {
        if drawable.kind == "circle" {
            println(f"Drawing circle with radius {drawable.radius}")
        } else if drawable.kind == "rectangle" {
            println(f"Drawing rectangle {drawable.width}x{drawable.height}")
        } else {
            println("Drawing shape")
        }
    }

    for shape in shapes {
        draw(shape)
    }

    println("\n=== Object Patterns Complete ===")
}