import APIClient
import SwiftUI
import WireProtocol

/// T-iOS-32 · 新建 Worktree（`POST /projects/worktree`，G）。
///
/// 表单只有两格：新分支名（必填、即时校验）+ 起点 ref（留空 = 当前 HEAD）。
/// 成功后展示服务器给的 canonical 路径/分支，并提供"在新 Worktree 开会话"——
/// 这就是 "spin up a worktree, land the winner, delete the rest" 循环的入口。
///
/// 安全：分支名先过 `WorktreeBranchRule`（校验先于网络）；服务器返回的路径/分支/
/// 错误文案都是不可信字节 → `Text(verbatim:)`。
struct WorktreeSheet: View {
    @State private var viewModel: WorktreeViewModel
    /// 创建成功（详情屏据此刷新 worktree 列表）。
    let onCreated: () -> Void
    /// "在新 worktree 开会话"：把服务器给的 canonical 路径交回详情屏的开会话钩子。
    let onOpenSession: (String) -> Void
    @Environment(\.dismiss) private var dismiss

    init(
        viewModel: WorktreeViewModel,
        onCreated: @escaping () -> Void,
        onOpenSession: @escaping (String) -> Void
    ) {
        _viewModel = State(initialValue: viewModel)
        self.onCreated = onCreated
        self.onOpenSession = onOpenSession
    }

    var body: some View {
        @Bindable var bindable = viewModel
        return NavigationStack {
            Form {
                if case .created(let path, let branch) = viewModel.createPhase {
                    createdSection(path: path, branch: branch)
                } else {
                    formSection(
                        branch: $bindable.branchText, base: $bindable.baseText
                    )
                }
            }
            .navigationTitle(WorktreeCopy.sheetTitle)
            .navigationBarTitleDisplayMode(.inline)
            .toolbar {
                ToolbarItem(placement: .cancellationAction) {
                    Button(WorktreeCopy.cancel) { dismiss() }
                }
            }
        }
    }

    @ViewBuilder private func formSection(
        branch: Binding<String>, base: Binding<String>
    ) -> some View {
        Section {
            TextField(WorktreeCopy.branchField, text: branch)
                .textInputAutocapitalization(.never)
                .autocorrectionDisabled()
                .submitLabel(.done)
                .onSubmit { submit() }
            TextField(WorktreeCopy.baseField, text: base)
                .textInputAutocapitalization(.never)
                .autocorrectionDisabled()
        } footer: {
            if let message = viewModel.branchValidationMessage {
                Text(message)
                    .font(DS.Typography.caption)
                    .foregroundStyle(DS.Palette.statusStuck)
            }
        }
        Section {
            Button {
                submit()
            } label: {
                if viewModel.createPhase == .creating {
                    ProgressView()
                        .frame(maxWidth: .infinity, minHeight: DS.Layout.minHitTarget)
                } else {
                    Label(WorktreeCopy.submit, systemImage: "plus.rectangle.on.folder")
                }
            }
            .buttonStyle(DSButtonStyle(kind: .primary))
            .disabled(!viewModel.canSubmitCreate)
            .listRowBackground(Color.clear)
            if case .failed(let message) = viewModel.createPhase {
                InlineMessage(text: message, tone: .error)
            }
        }
    }

    @ViewBuilder private func createdSection(path: String, branch: String) -> some View {
        Section(WorktreeCopy.createdTitle) {
            VStack(alignment: .leading, spacing: DS.Space.xs4) {
                Text(verbatim: branch)
                    .font(DS.Typography.callout)
                    .foregroundStyle(DS.Palette.textPrimary)
                Text(verbatim: path)
                    .font(DS.Typography.mono(.caption))
                    .foregroundStyle(DS.Palette.textSecondary)
                    .lineLimit(2)
                    .truncationMode(.middle)
            }
        }
        Section {
            Button {
                DS.Haptics.selection()
                onOpenSession(path)
                dismiss()
            } label: {
                Label(WorktreeCopy.openInNewWorktree, systemImage: "terminal.fill")
            }
            .buttonStyle(DSButtonStyle(kind: .primary))
            .disabled(path.isEmpty)
            .listRowBackground(Color.clear)
            Button(WorktreeCopy.cancel) { dismiss() }
                .buttonStyle(DSButtonStyle(kind: .secondary))
                .listRowBackground(Color.clear)
        }
    }

    private func submit() {
        Task {
            await viewModel.create()
            if case .created = viewModel.createPhase {
                DS.Haptics.success()
                onCreated() // 详情屏刷新（新 worktree 立刻出现在列表里）
            }
        }
    }
}