//
//  TimeWidgetLiveActivity.swift
//  TimeWidget
//
//  Created by 송예찬 on 6/13/26.
//

import ActivityKit
import WidgetKit
import SwiftUI

struct TimeWidgetLiveActivity: Widget {
    var body: some WidgetConfiguration {
        ActivityConfiguration(for: TimerAttributes.self) { context in
            // Lock Screen / Notification Banner
            // Text(timerInterval:) is a system primitive that counts down in real time
            // without waking the app — no Timer or polling needed.
            HStack(spacing: 14) {
                Image(systemName: "timer")
                    .font(.title2.weight(.semibold))
                    .foregroundStyle(.white)

                VStack(alignment: .leading, spacing: 2) {
                    Text(context.attributes.sessionName)
                        .font(.caption)
                        .foregroundStyle(.white.opacity(0.75))

                    let safeEnd = max(Date.now, context.state.endDate)
                    Text(timerInterval: Date.now...safeEnd, countsDown: true)
                        .font(.title.monospacedDigit().bold())
                        .foregroundStyle(.white)
                }

                Spacer()
            }
            .padding(.horizontal, 20)
            .padding(.vertical, 14)
            .activityBackgroundTint(Color(red: 0.07, green: 0.07, blue: 0.18))
            .activitySystemActionForegroundColor(.white)

        } dynamicIsland: { context in
            DynamicIsland {
                // Expanded — shown when the user long-presses the Dynamic Island.
                DynamicIslandExpandedRegion(.leading) {
                    Label(context.attributes.sessionName, systemImage: "timer")
                        .font(.caption)
                        .foregroundStyle(.secondary)
                        .lineLimit(1)
                }
                DynamicIslandExpandedRegion(.trailing) {
                    EmptyView()
                }
                DynamicIslandExpandedRegion(.center) {
                    let safeEnd = max(Date.now, context.state.endDate)
                    Text(timerInterval: Date.now...safeEnd, countsDown: true)
                        .font(.title2.monospacedDigit().bold())
                        .foregroundStyle(.primary)
                }
                DynamicIslandExpandedRegion(.bottom) {
                    Text("Stay focused")
                        .font(.caption2)
                        .foregroundStyle(.tertiary)
                }
            } compactLeading: {
                Image(systemName: "timer")
                    .foregroundStyle(.indigo)
            } compactTrailing: {
                let safeEnd = max(Date.now, context.state.endDate)
                Text(timerInterval: Date.now...safeEnd, countsDown: true)
                    .font(.caption.monospacedDigit().bold())
                    .foregroundStyle(.primary)
                    .frame(width: 52)
            } minimal: {
                Image(systemName: "timer")
                    .foregroundStyle(.indigo)
            }
            .keylineTint(.indigo)
        }
    }
}

// MARK: - Previews

extension TimerAttributes {
    fileprivate static var preview: TimerAttributes {
        TimerAttributes(sessionName: "Deep Work")
    }
}

extension TimerAttributes.ContentState {
    fileprivate static var active: TimerAttributes.ContentState {
        TimerAttributes.ContentState(endDate: Date.now.addingTimeInterval(22 * 60))
    }
    fileprivate static var nearEnd: TimerAttributes.ContentState {
        TimerAttributes.ContentState(endDate: Date.now.addingTimeInterval(2 * 60))
    }
}

#Preview("Notification", as: .content, using: TimerAttributes.preview) {
    TimeWidgetLiveActivity()
} contentStates: {
    TimerAttributes.ContentState.active
    TimerAttributes.ContentState.nearEnd
}