// How every screen that loads data shows it: a static "Loading" before the first answer, the error
// and Try again when there is nothing to show, and once content is on screen, a small dim line under
// it when a refresh fails. Content is never replaced by an error.

import SwiftUI

/// The placeholder before a screen's first answer, the same as the feed's. Static, with no spinner.
struct LoadingText: View {
    var body: some View {
        Text("Loading")
            .font(.system(size: 15, weight: .semibold))
            .foregroundStyle(Theme.secondaryText)
            .frame(maxWidth: .infinity, alignment: .leading)
            .padding(.horizontal, 8)
            .padding(.top, 4)
    }
}

/// What a screen shows under its content about loading. `loaded` is true once content is on screen.
/// Before then: Loading, or the error with Try again when `retry` is set. After: only a failed
/// refresh's error, small and dim.
struct LoadStatus: View {
    var loaded: Bool
    var error: String?
    var retry: (() async -> Void)?

    var body: some View {
        if let error {
            if loaded {
                Text(error)
                    .font(.system(size: 11))
                    .foregroundStyle(Theme.done)
                    .lineLimit(3)
                    .frame(maxWidth: .infinity, alignment: .leading)
                    .padding(.horizontal, 8)
            } else {
                VStack(alignment: .leading, spacing: 8) {
                    Text(error)
                        .font(.system(size: 12))
                        .foregroundStyle(Theme.secondaryText)
                        .padding(.horizontal, 8)
                    if let retry {
                        Button("Try again") { Task { await retry() } }
                            .buttonStyle(PillButtonStyle(fill: Theme.control, foreground: .white))
                    }
                }
                .frame(maxWidth: .infinity, alignment: .leading)
            }
        } else if !loaded {
            LoadingText()
        }
    }
}