import SwiftUI

/// A repository's wiki pages, landing page first.
struct WikiView: View {

    @State private var model: WikiViewModel

    init(client: GitbayClient, repo: String) {
        _model = State(initialValue: WikiViewModel(client: client, repoPath: repo))
    }

    /// The landing page leads, then the rest in the order the server
    /// gave them — the same order the web's sidebar shows.
    private var ordered: [String] {
        guard let listing = model.state.value else { return [] }
        guard let home = listing.home else { return listing.pages }
        return [home] + listing.pages.filter { $0 != home }
    }

    var body: some View {
        List {
            ForEach(ordered, id: \.self) { page in
                NavigationLink(value: RepoRoute.wikiPage(
                    repo: model.repoPath, page: page
                )) {
                    HStack(spacing: 8) {
                        Label(page, systemImage: "doc.text")
                            .font(.gbSans(.subheadline))
                        if page == model.state.value?.home {
                            GBChip("home", .gbAccent)
                        }
                    }
                }
            }
        }
        .overlay { LoadStateOverlay(state: model.state) }
        .navigationTitle("Wiki")
        .navigationBarTitleDisplayMode(.inline)
        .task { await model.load() }
        .refreshable { await model.load() }
    }
}

/// One wiki page, rendered by its format — the pages here are .org as
/// often as .md, so ReadmeView picks the renderer.
struct WikiPageView: View {

    @State private var model: WikiPageViewModel

    init(client: GitbayClient, repo: String, page: String) {
        _model = State(initialValue: WikiPageViewModel(
            client: client, repoPath: repo, page: page
        ))
    }

    var body: some View {
        ScrollView {
            if let page = model.state.value {
                if page.isBinary {
                    ContentUnavailableView {
                        Label("Not a page", systemImage: "doc.zipper")
                    } description: {
                        Text(page.file)
                    }
                } else if let content = page.content {
                    ReadmeView(name: page.file, content: content)
                        .padding(.horizontal, 16)
                        .padding(.vertical, 12)
                        .frame(maxWidth: .infinity, alignment: .leading)
                }
            }
        }
        .overlay { LoadStateOverlay(state: model.state) }
        .navigationTitle(model.page)
        .navigationBarTitleDisplayMode(.inline)
        .task { await model.load() }
        .refreshable { await model.load() }
    }
}