// What a file approval would edit, shown on the feed card and the thread screen in place of the raw
// prompt. Claude sends no diff before approval, so most show the file name alone.

import SwiftUI

/// "Wants to edit" over one file, or "Wants to edit 3 files" over a row for each: the name in
/// monospace and, when the gateway counted them, the lines added and removed on the right. On the
/// thread screen the title is amber and one file's first changed lines follow, removed in red and
/// added in green. Past `limit` files, one line counts the rest.
struct FileEditRows: View {
    var edit: FileEdit
    var limit = Int.max
    var inThread = false

    var body: some View {
        VStack(alignment: .leading, spacing: 2) {
            Text(edit.title)
                .font(.system(size: inThread ? 11 : 12, weight: inThread ? .semibold : .regular))
                .foregroundStyle(inThread ? Theme.you : Theme.secondaryText)
            ForEach(edit.files.prefix(limit)) { file in
                HStack(spacing: 6) {
                    Text(code: file.name)
                        .foregroundStyle(.white)
                        .lineLimit(1)
                        .truncationMode(.middle)
                    Spacer(minLength: 4)
                    if let counts = counts(file) {
                        counts
                            .lineLimit(1)
                            .layoutPriority(1)
                    }
                }
                .font(.system(size: 12))
            }
            if edit.files.count > limit {
                Text("\(edit.files.count - limit) more")
                    .font(.system(size: 11))
                    .foregroundStyle(Theme.secondaryText)
            }
            if inThread, !edit.preview.isEmpty {
                VStack(alignment: .leading, spacing: 1) {
                    ForEach(edit.preview) { line in
                        Text(code: line.text)
                            .foregroundStyle(color(line.change))
                            .lineLimit(1)
                    }
                }
                .font(.system(size: 11))
                .padding(.top, 4)
            }
        }
        .accessibilityElement(children: .combine)
    }

    /// "+9 −6" in monospace, green and red, leaving out a count the gateway did not send.
    private func counts(_ file: PendingFile) -> Text? {
        let parts = [
            file.counts.additions.map { Text(code: $0).foregroundStyle(Theme.add) },
            file.counts.deletions.map { Text(code: $0).foregroundStyle(Theme.bad) },
        ].compactMap(\.self)
        guard let first = parts.first else { return nil }
        return parts.dropFirst().reduce(first) { Text("\($0)\(Text(code: " "))\($1)") }
    }

    private func color(_ change: FileEdit.Line.Change) -> Color {
        switch change {
        case .added: Theme.add
        case .removed: Theme.bad
        case .context: Theme.secondaryText
        }
    }
}