import RastrilloApple
import SwiftUI

@MainActor struct DocsSharingView: View {
    let client: NativeHTTP
    let sqid: String
    @Environment(\.dismiss) private var dismiss
    @State private var information: DocsShareInformation?
    @State private var address = ""
    @State private var role = "reader"
    @State private var busy = false
    @State private var needsRefresh = true
    @State private var errorKey: String?
    @State private var oneTimeURL: URL?

    var body: some View {
        NavigationStack {
            Form {
                if let errorKey {
                    Section {
                        Text(LocalizedStringKey(errorKey), bundle: DocsResources.bundle)
                        Button { Task { await refresh() } } label: { label("native.retry") }
                            .disabled(busy)
                    }
                }
                if busy { ProgressView() }
                if let information {
                    Section {
                        if information.grants.isEmpty { label("docs.share.empty") }
                        ForEach(information.grants) { grant in
                            VStack(alignment: .leading) {
                                Text(verbatim: grant.address).textSelection(.enabled)
                                label(grant.role == "writer" ? "docs.share.role.writer" : "docs.share.role.reader")
                                    .foregroundStyle(.secondary)
                                Button(role: .destructive) {
                                    Task { await change("/revoke", values: ["address": grant.address]) }
                                } label: { label("docs.share.revoke") }
                                .disabled(busy || needsRefresh)
                            }
                        }
                    } header: { label("docs.share.heading") }
                    Section {
                        TextField(String(localized: "docs.share.address", bundle: DocsResources.bundle), text: $address)
                            .autocorrectionDisabled()
                            #if os(iOS)
                            .textInputAutocapitalization(.never)
                            .keyboardType(.emailAddress)
                            #endif
                        Picker(selection: $role) {
                            label("docs.share.role.reader").tag("reader")
                            label("docs.share.role.writer").tag("writer")
                        } label: { label("docs.share.role") }
                        Button { Task { await change("", values: ["address": address, "role": role]) } } label: { label("docs.share.submit") }
                            .disabled(busy || needsRefresh || address.trimmingCharacters(in: .whitespacesAndNewlines).isEmpty)
                    }.disabled(busy)
                    Section {
                        label("docs.share.public.body")
                        if let oneTimeURL {
                            Text(verbatim: oneTimeURL.absoluteString).textSelection(.enabled)
                            ShareLink(item: oneTimeURL) { label("docs.share.submit") }
                            label("docs.share.public.once").foregroundStyle(.secondary)
                        } else if information.published {
                            label("docs.share.public.published").foregroundStyle(.secondary)
                        }
                        if information.published {
                            Button { Task { await change("/link", values: ["on": "1"]) } } label: { label("docs.share.public.replace") }
                            Button(role: .destructive) { Task { await change("/link", values: ["on": "0"]) } } label: { label("docs.share.public.off") }
                        } else {
                            Button { Task { await change("/link", values: ["on": "1"]) } } label: { label("docs.share.public.on") }
                        }
                    } header: { label("docs.share.public.heading") }
                        footer: { label("docs.share.public.hint") }
                        .disabled(busy || needsRefresh)
                }
            }
            .formStyle(.grouped)
            .navigationTitle(Text("docs.share.title", bundle: DocsResources.bundle))
            .toolbar { ToolbarItem(placement: .confirmationAction) {
                Button { dismiss() } label: { label("docs.share.back") }.disabled(busy)
            } }
            .task(id: sqid) { await refresh() }
            .interactiveDismissDisabled(busy)
            #if os(macOS)
            .frame(minWidth: 460, idealWidth: 540, minHeight: 520)
            #endif
        }
    }

    private func label(_ key: String) -> Text { Text(LocalizedStringKey(key), bundle: DocsResources.bundle) }

    private func load() async throws {
        let state: DocsShareInformation = try await client.request("/d/\(sqid)/share")
        information = state
        if !state.published { oneTimeURL = nil }
        else if !state.public_url.isEmpty { oneTimeURL = URL(string: state.public_url) }
        needsRefresh = false
    }

    private func refresh() async {
        guard !busy else { return }
        busy = true
        defer { busy = false }
        errorKey = nil
        do { try await load() }
        catch { needsRefresh = true; errorKey = "native.share.loadFailed" }
    }

    private func change(_ suffix: String, values: [String: String]) async {
        guard !busy && !needsRefresh else { return }
        busy = true
        errorKey = nil
        defer { busy = false }
        // URL query encoding leaves '+' literal; forms interpret it as space.
        var components = URLComponents()
        components.queryItems = values.sorted { $0.key < $1.key }.map { URLQueryItem(name: $0.key, value: $0.value) }
        let body = Data((components.percentEncodedQuery ?? "").replacingOccurrences(of: "+", with: "%2B").utf8)
        do {
            let result: DocsShareMutation = try await client.request("/d/\(sqid)/share\(suffix)", method: "POST", body: body, contentType: "application/x-www-form-urlencoded")
            if suffix == "/link" {
                guard let published = result.published else { throw NativeClientError.message("Invalid sharing response") }
                oneTimeURL = published ? result.public_url.flatMap(URL.init(string:)) : nil
            } else {
                guard result.ok == true else { throw NativeClientError.message("Invalid sharing response") }
                if suffix.isEmpty { address = "" }
            }
            do { try await load() }
            catch { needsRefresh = true; errorKey = "native.share.loadFailed" }
        } catch { needsRefresh = true; errorKey = "native.share.saveFailed" }
    }
}