birthday.swift

import Foundation

struct AnimatedBirthdayCake {
    let name: String
    
    // Tier character widths
    private let topWidth = 21
    private let midWidth = 25
    private let baseWidth = 29
    
    // ANSI Controls
    private let clearScreen = "\u{001B}[2J\u{001B}[H"
    private let hideCursor  = "\u{001B}[?25l"
    private let showCursor  = "\u{001B}[?25h"
    private let homeCursor  = "\u{001B}[H"
    
    // MARK: - Cake Renderer
    func render(candleStates: [String], confetti: [String] = []) -> String {
        var lines: [String] = []
        
        // Optional top confetti line
        if !confetti.isEmpty {
            lines.append(confetti.joined(separator: "   "))
        } else {
            lines.append("")
        }
        
        // 1. Candles (exact centering: 5 spaces indent)
        let candlePad = String(repeating: " ", count: 5)
        lines.append(candlePad + candleStates.joined(separator: "  "))
        
        // 2. Tier 1 - Top
        let topPad = String(repeating: " ", count: (baseWidth - topWidth) / 2)
        lines.append(topPad + "┌" + String(repeating: "─", count: topWidth - 2) + "┐")
        lines.append(topPad + "│" + center("* H A P P Y *", width: topWidth - 2) + "│")
        
        // 3. Tier 2 - Middle
        let midPad = String(repeating: " ", count: (baseWidth - midWidth) / 2)
        let step1 = (midWidth - topWidth) / 2
        lines.append(midPad + "┌" + String(repeating: "─", count: step1 - 1) + "┴" + String(repeating: "─", count: topWidth - 2) + "┴" + String(repeating: "─", count: step1 - 1) + "┐")
        lines.append(midPad + "│" + center("B I R T H D A Y", width: midWidth - 2) + "│")
        
        // 4. Tier 3 - Base
        let step2 = (baseWidth - midWidth) / 2
        let nameTag = "\(name.uppercased())"
        lines.append("┌" + String(repeating: "─", count: step2 - 1) + "┴" + String(repeating: "─", count: midWidth - 2) + "┴" + String(repeating: "─", count: step2 - 1) + "┐")
        lines.append("│" + center(nameTag, width: baseWidth - 2) + "│")
        lines.append("└" + String(repeating: "─", count: baseWidth - 2) + "┘")
        
        return lines.joined(separator: "\n")
    }
    
    private func center(_ text: String, width: Int) -> String {
        let leftPad = (width - text.count) / 2
        let rightPad = width - text.count - leftPad
        return String(repeating: " ", count: leftPad) + text + String(repeating: " ", count: rightPad)
    }
    
    // MARK: - Animation Sequence
    func animate() async throws {
        print(clearScreen + hideCursor, terminator: "")
        defer { print(showCursor) }
        
        // Phase 1: Flickering Candles (10 frames)
        let flickerVariations = [
            ["🕯️", "🕯️", "🕯️", "🕯️", "🕯️"],
            ["✨", "🕯️", "🕯️", "✨", "🕯️"],
            ["🕯️", "✨", "🕯️", "🕯️", "✨"],
            ["🕯️", "🕯️", "✨", "🕯️", "🕯️"]
        ]
        
        for i in 0..<12 {
            let state = flickerVariations[i % flickerVariations.count]
            print(homeCursor + render(candleStates: state) + "\n\n  🎂 Make a wish, Tim...")
            try await Task.sleep(for: .milliseconds(250))
        }
        
        // Phase 2: Blowing out candles one by one (left to right)
        var candles = ["🕯️", "🕯️", "🕯️", "🕯️", "🕯️"]
        for i in 0..<5 {
            candles[i] = "💨"
            print(homeCursor + render(candleStates: candles) + "\n\n  💨 *Ffffffffff...*       ")
            try await Task.sleep(for: .milliseconds(220))
        }
        
        try await Task.sleep(for: .milliseconds(400))
        
        // Phase 3: Confetti Burst Celebration (15 frames)
        let confettiShapes = ["🎉", "✨", "🎈", "⭐️", "🎊", "🥳"]
        for _ in 0..<16 {
            let row = (0..<6).map { _ in confettiShapes.randomElement()! }
            print(homeCursor + render(candleStates: ["💨", "💨", "💨", "💨", "💨"], confetti: row) + "\n\n  🎉 HAPPY BIRTHDAY, TIM! 🥳")
            try await Task.sleep(for: .milliseconds(200))
        }
    }
}

// MARK: - Run
let cake = AnimatedBirthdayCake(name: "Tim")
try await cake.animate()