import ByreAPI
import OpenAPIRuntime
import SwiftUI

typealias Attachment = Components.Schemas.Attachment
typealias InboxResponseCreate = Components.Schemas.InboxResponseCreate

private let delegateText = "Use your judgment for this decision and continue within the existing task instructions."
private let otherStop = "\u{0}other"
private let httpURL = Re(#"^https?://"#, caseless: true)

private func numberChoices(_ blocks: [MDBlock], _ next: inout Int) -> [MDBlock] {
    blocks.map { block in
        switch block {
        case .list(let ordered, let start, let items, let grid):
            return .list(ordered: ordered, start: start, items: items.map { item in
                var out = item
                if item.choice != nil {
                    out.choiceIndex = next
                    next += 1
                }
                out.blocks = numberChoices(item.blocks, &next)
                return out
            }, grid: grid)
        case .quote(let inner):
            return .quote(numberChoices(inner, &next))
        case .details(let summary, let body):
            return .details(summary: summary, body: numberChoices(body, &next))
        default:
            return block
        }
    }
}

private func firstChoices(_ blocks: [MDBlock], _ out: inout [String: Int]) {
    for block in blocks {
        switch block {
        case .list(_, _, let items, _):
            for item in items {
                if let c = item.choice, out[c] == nil {
                    out[c] = item.choiceIndex
                }
                firstChoices(item.blocks, &out)
            }
        case .quote(let inner):
            firstChoices(inner, &out)
        case .details(_, let body):
            firstChoices(body, &out)
        default:
            break
        }
    }
}

@MainActor
@Observable
private final class CardModel {
    let item: InboxItem
    let store: Store
    let overlays: Overlays
    let context: [MDBlock]
    let firstChoice: [String: Int]
    var busy = false
    @ObservationIgnored var shown: Set<String> = []

    init(_ item: InboxItem, _ store: Store, _ overlays: Overlays) {
        self.item = item
        self.store = store
        self.overlays = overlays
        var next = 0
        context = numberChoices(parseMarkdown(jsString(item.payload.value["context"] ?? ""), choices: true), &next)
        var first: [String: Int] = [:]
        firstChoices(context, &first)
        firstChoice = first
    }

    var payload: JSONDict {
        item.payload.value
    }

    var key: String {
        "inbox:\(item.id)"
    }

    var options: [String] {
        (payload["options"] as? [(any Sendable)?] ?? []).compactMap { $0 as? String }
    }

    var recommended: [String] {
        (payload["recommended"] as? [(any Sendable)?] ?? []).compactMap { $0 as? String }
    }

    var multiple: Bool {
        bool(payload, "multiple")
    }

    var answered: Bool {
        item.state != .open
    }

    var chosen: [String] {
        item.responses.flatMap { $0.options ?? [] }
    }

    var checked: [String] {
        answered ? chosen : store.drafts?.checkedAnswer(item.id) ?? []
    }

    var hasImages: Bool {
        !store.images.images(key).isEmpty
    }

    var typed: String {
        trimmed(store.drafts?.textAnswer(item.id) ?? "")
    }

    var editorOpen: Bool {
        (store.drafts?.hasTextAnswer(item.id) ?? false) || hasImages
    }

    func toggle(_ text: String, _ on: Bool) {
        var now = checked.filter { $0 != text }
        if on {
            now.append(text)
        }
        store.drafts?.setCheckedAnswer(item.id, options.filter { now.contains($0) })
    }

    func pick(_ text: String) {
        if busy || answered {
            return
        }
        if multiple {
            toggle(text, !checked.contains(text))
            return
        }
        submit(InboxResponseCreate(itemId: item.id, _type: .option, options: [text]))
    }

    func submit(_ response: InboxResponseCreate, withImages: Bool = false) {
        if busy {
            return
        }
        busy = true
        let imgs = withImages ? store.images.take(key) : []
        Task {
            do {
                var r = response
                r.images = try await uploadImages(store.api, imgs)
                _ = try await store.api.client.respondInbox(body: .json(.init(responses: [r]))).ok
                store.drafts?.clearAnswer(item.id)
                store.paneFocus.setDraft(key, false)
            } catch {
                store.images.restore(key, imgs)
                overlays.showAlert(errorText(error))
                busy = false
            }
        }
    }

    func submitQuestion() {
        let opts = multiple ? checked : []
        if !opts.isEmpty {
            submit(InboxResponseCreate(itemId: item.id, _type: .option, options: opts, text: typed.isEmpty ? nil : store.drafts?.textAnswer(item.id)), withImages: true)
            return
        }
        if !typed.isEmpty || hasImages {
            submit(InboxResponseCreate(itemId: item.id, _type: .other, text: store.drafts?.textAnswer(item.id) ?? ""), withImages: true)
        }
    }
}

struct QuestionCard: View {
    let item: InboxItem
    @Environment(Store.self) private var store
    @Environment(Overlays.self) private var overlays
    @ViewState private var model: CardModel?
    @FocusState private var focus: String?

    var body: some View {
        VStack(spacing: 0) {
            if let model {
                VStack(alignment: .leading, spacing: 0) {
                    HStack(alignment: .firstTextBaseline, spacing: 10) {
                        Text("question\(model.answered ? " · \(item.state.rawValue)" : "")")
                        Spacer(minLength: 0)
                        Text(ago(item.createdAt)).help(isoText(item.createdAt))
                    }
                    .font(Fonts.font(11))
                    .foregroundStyle(Palette.muted)
                    CardBody(model: model, focus: $focus)
                    Thread(item: item)
                    if !model.answered {
                        CardActions(model: model, focus: $focus)
                            .padding(.top, 6)
                    }
                }
                .onKeyPress(keys: [.downArrow, .upArrow]) { press in
                    move(model, press.key == .downArrow ? 1 : -1)
                }
            }
        }
        .frame(maxWidth: .infinity, alignment: .leading)
        .onAppear {
            if model == nil {
                model = CardModel(item, store, overlays)
            }
        }
    }

    private func move(_ model: CardModel, _ by: Int) -> KeyPress.Result {
        var stops = model.firstChoice.filter { model.shown.contains($0.key) }.sorted { $0.value < $1.value }.map(\.key)
        if !model.editorOpen {
            stops.append(otherStop)
        }
        guard let current = focus, let at = stops.firstIndex(of: current) else {
            return .ignored
        }
        focus = stops[min(max(at + by, 0), stops.count - 1)]
        return .handled
    }
}

struct QuestionDetails: View {
    let item: InboxItem
    @Environment(Store.self) private var store
    @Environment(Overlays.self) private var overlays
    @ViewState private var model: CardModel?
    @FocusState private var focus: String?

    var body: some View {
        VStack(alignment: .leading, spacing: 0) {
            if let model {
                CardBody(model: model, focus: $focus, question: false)
                Thread(item: item)
            }
        }
        .frame(maxWidth: .infinity, alignment: .leading)
        .onAppear {
            if model == nil {
                model = CardModel(item, store, overlays)
            }
        }
    }
}

private struct CardBody: View {
    let model: CardModel
    var focus: FocusState<String?>.Binding
    var question = true
    @ViewState private var wide = true

    private var contextCtx: MDContext {
        MDContext(taskId: model.item.taskId, choice: { md, first in
            AnyView(ChoiceBox(model: model, item: md, first: first, ctx: self.contextCtx, focus: focus))
        }, gridColumns: wide ? 4 : 2)
    }

    var body: some View {
        let p = model.payload
        let item = model.item
        VStack(alignment: .leading, spacing: 0) {
            MarkdownView(blocks: model.context, ctx: contextCtx)
                .onGeometryChange(for: Bool.self) { $0.size.width > 480 } action: { wide = $0 }
                .padding(.vertical, 10)
            if question {
                MarkdownView(blocks: parseMarkdown(jsString(p["question"] ?? "")), ctx: MDContext(taskId: item.taskId))
                    .padding(.top, 10)
                    .padding(.bottom, 4)
            }
            WhyLine(text: jsString(p["why_blocked"] ?? ""), taskId: item.taskId)
                .padding(.bottom, 8)
            Attachments(list: attachments(p["attachments"] ?? nil), taskId: item.taskId)
        }
    }

    private func attachments(_ v: (any Sendable)?) -> [Attachment] {
        guard let v else {
            return []
        }
        do {
            return try jsonDecoder().decode([Attachment].self, from: try JSONEncoder().encode(try OpenAPIValueContainer(unvalidatedValue: v)))
        } catch {
            log.error("decode attachments: \(String(describing: error), privacy: .public)")
            return []
        }
    }
}

private struct WhyLine: View {
    let text: String
    let taskId: String
    @Environment(Store.self) private var store

    var body: some View {
        var out = AttributedString("Blocked on: ")
        out.foregroundColor = Palette.text
        var rest = InlineRenderer(store: store, size: 13, taskId: taskId).text(parseInline(text))
        rest.foregroundColor = rest.foregroundColor ?? Palette.muted
        return Text(out + rest)
            .foregroundStyle(Palette.muted)
            .textSelection(.enabled)
            .fixedSize(horizontal: false, vertical: true)
    }
}

private struct ChoiceBox: View {
    let model: CardModel
    let item: MDItem
    let first: Bool
    let ctx: MDContext
    var focus: FocusState<String?>.Binding
    @Environment(Store.self) private var store
    @ViewState private var hover = false

    var body: some View {
        let text = item.choice ?? ""
        if model.options.contains(text) && model.firstChoice[text] == item.choiceIndex {
            box(text)
        } else {
            HStack(alignment: .firstTextBaseline, spacing: 6) {
                Text("•")
                VStack(alignment: .leading, spacing: 6) {
                    InlineView(inlines: parseInline(item.raw), ctx: MDContext(taskId: model.item.taskId))
                    ItemBody(item: item, ctx: ctx)
                }
            }
        }
    }

    private func box(_ text: String) -> some View {
        let rec = model.recommended.contains(text)
        let focused = focus.wrappedValue == text
        let picked = model.answered && model.chosen.contains(text)
        let lit = (hover && !model.multiple && !model.answered) || focused || picked
        let hasDetail = !item.inline.isEmpty || !item.blocks.isEmpty
        let on = model.checked.contains(text)
        let keys: Set<KeyEquivalent> = model.multiple ? [.space] : [.return, .space]
        return VStack(alignment: .leading, spacing: 0) {
            HStack(alignment: .firstTextBaseline, spacing: 10) {
                if model.multiple {
                    Toggle("", isOn: Binding(get: { on }, set: { model.toggle(text, $0) }))
                        .toggleStyle(.checkbox)
                        .labelsHidden()
                        .tint(Palette.accent)
                        .disabled(model.busy || model.answered)
                }
                InlineView(inlines: parseInline(text), ctx: MDContext(taskId: model.item.taskId, weight: 600))
                    .frame(maxWidth: .infinity, alignment: .leading)
                if picked {
                    Text("chosen")
                        .font(Fonts.font(11))
                        .foregroundStyle(Palette.accent)
                        .allowsHitTesting(false)
                }
                if rec {
                    Text("recommended")
                        .font(Fonts.font(11))
                        .foregroundStyle(Palette.ok)
                        .allowsHitTesting(false)
                }
            }
            .padding(.horizontal, 10)
            .padding(.vertical, 6)
            .background {
                (lit ? Palette.accentTint : rec ? Palette.ok.opacity(0.12) : Palette.surface)
                    .onTapGesture {
                        model.pick(text)
                    }
            }
            if hasDetail {
                ItemBody(item: MDItem(inline: item.inline, blocks: item.blocks), ctx: ctx)
                    .padding(.horizontal, 10)
                    .padding(.vertical, 8)
                    .overlay(alignment: .top) {
                        Rectangle().fill(Palette.border).frame(height: 1)
                    }
            }
        }
        .frame(maxWidth: .infinity, maxHeight: .infinity, alignment: .topLeading)
        .background {
            Palette.raised
                .onTapGesture {
                    model.pick(text)
                }
        }
        .environment(\.choiceTap, { [model] in
            model.pick(text)
        })
        .clipShape(RoundedRectangle(cornerRadius: 6))
        .overlay(RoundedRectangle(cornerRadius: 6).stroke(lit ? Palette.accent : rec ? Palette.ok.opacity(0.55) : Palette.border))
        .overlay {
            if focused {
                RoundedRectangle(cornerRadius: 6).stroke(Palette.accent, lineWidth: 2).padding(-2)
            }
        }
        .opacity(model.busy && !model.multiple ? 0.6 : 1)
        .contentShape(Rectangle())
        .focusable(!model.busy && !model.answered)
        .focusEffectDisabled()
        .focused(focus, equals: text)
        .onKeyPress(keys: keys) { _ in
            model.pick(text)
            return .handled
        }
        .onHover { hover = $0 }
        .onAppear {
            model.shown.insert(text)
        }
        .onDisappear {
            model.shown.remove(text)
        }
        .padding(.top, first ? 0 : 6)
    }
}

private struct CardActions: View {
    let model: CardModel
    var focus: FocusState<String?>.Binding

    var body: some View {
        let disabled = model.typed.isEmpty && !model.hasImages && (!model.multiple || model.checked.isEmpty)
        VStack(alignment: .leading, spacing: 6) {
            TextEntry(model: model, focus: focus) {
                model.submitQuestion()
            }
            HStack(spacing: 8) {
                Button("Let the agent decide") {
                    model.submit(InboxResponseCreate(itemId: model.item.id, _type: .other, text: delegateText))
                }
                .buttonStyle(WebButtonStyle())
                Spacer()
                Button("Submit") {
                    model.submitQuestion()
                }
                .buttonStyle(WebButtonStyle(primary: true))
                .disabled(disabled)
            }
            .disabled(model.busy)
        }
    }
}

private struct TextEntry: View {
    let model: CardModel
    var focus: FocusState<String?>.Binding
    let go: () -> Void
    @Environment(Store.self) private var store
    @Environment(Overlays.self) private var overlays
    @Environment(\.paneAccent) private var accent
    @FocusState private var editing: Bool
    @ViewState private var hover = false
    @ViewState private var targeted = false

    var body: some View {
        let id = model.item.id
        let key = model.key
        let text = Binding(get: { store.drafts?.textAnswer(id) ?? "" }, set: { v in
            store.drafts?.setTextAnswer(id, v)
            store.paneFocus.setDraft(key, !trimmed(v).isEmpty)
        })
        let focused = focus.wrappedValue == otherStop
        Group {
            if model.editorOpen {
                VStack(alignment: .leading, spacing: 6) {
                    Thumbnails(key: key)
                    TextEditor(text: text)
                        .font(Fonts.font(13))
                        .scrollContentBackground(.hidden)
                        .focused($editing)
                        .disabled(model.busy)
                        .focusedValue(\.composer, ComposerTarget(paste: { pb in store.images.add(key, pasteboard: pb, overlays) }))
                        .onKeyPress(.return, phases: .down) { press in
                            let marked = (NSApp.keyWindow?.firstResponder as? NSTextView)?.hasMarkedText() ?? false
                            if press.modifiers.contains(.shift) || marked {
                                return .ignored
                            }
                            go()
                            return .handled
                        }
                        .padding(.horizontal, 5)
                        .padding(.vertical, 6)
                        .frame(height: 66)
                        .background(Palette.raised, in: RoundedRectangle(cornerRadius: 6))
                        .overlay(alignment: .topLeading) {
                            if text.wrappedValue.isEmpty {
                                Text("Your answer, a question back, or new instructions")
                                    .foregroundStyle(Palette.muted)
                                    .padding(.horizontal, 10)
                                    .padding(.vertical, 6)
                                    .allowsHitTesting(false)
                            }
                        }
                        .overlay(RoundedRectangle(cornerRadius: 6).stroke(targeted || editing ? Palette.accent : Palette.border))
                        .overlay {
                            Color.clear
                                .contentShape(Rectangle())
                                .allowsHitTesting(false)
                                .onDrop(of: [.image, .fileURL], isTargeted: $targeted) { providers in
                                    store.images.add(key, providers: providers, overlays)
                                    return true
                                }
                        }
                }
                .onChange(of: editing) {
                    if !editing {
                        if trimmed(text.wrappedValue).isEmpty && !model.hasImages && !model.busy {
                            store.drafts?.dropTextAnswer(id)
                        }
                        store.drafts?.flush()
                    }
                }
            } else {
                Text("Other…")
                    .foregroundStyle(Palette.muted)
                    .padding(.horizontal, 10)
                    .padding(.vertical, 4)
                    .frame(maxWidth: .infinity, alignment: .leading)
                    .overlay(RoundedRectangle(cornerRadius: 6).stroke(hover || focused ? Palette.accent : Palette.border))
                    .overlay {
                        if focused {
                            RoundedRectangle(cornerRadius: 6).stroke(Palette.accent, lineWidth: 2).padding(-2)
                        }
                    }
                    .opacity(model.busy ? 0.6 : 1)
                    .contentShape(Rectangle())
                    .focusable(!model.busy)
                    .focusEffectDisabled()
                    .focused(focus, equals: otherStop)
                    .onTapGesture {
                        open()
                    }
                    .onKeyPress(keys: [.return, .space]) { _ in
                        open()
                        return .handled
                    }
                    .onHover { hover = $0 }
            }
        }
        .onDisappear {
            store.paneFocus.setDraft(key, false)
        }
    }

    private func open() {
        if model.busy {
            return
        }
        store.drafts?.setTextAnswer(model.item.id, "")
        DispatchQueue.main.async {
            editing = true
        }
    }
}

private struct Thread: View {
    let item: InboxItem

    var body: some View {
        if !item.responses.isEmpty {
            VStack(alignment: .leading, spacing: 2) {
                ForEach(item.responses, id: \.id) { r in
                    let images = r.images.isEmpty ? "" : " (\(r.images.count == 1 ? "1 image" : "\(r.images.count) images"))"
                    let rest = " \(r._type.rawValue.replacingOccurrences(of: "_", with: " "))\(r.options.map { ": \($0.joined(separator: "; "))" } ?? "")\(r.text.map { " — \($0)" } ?? "")\(images)"
                    Text("\(Text(r.user).font(Fonts.font(11, weight: 700)))\(rest)")
                        .textSelection(.enabled)
                        .fixedSize(horizontal: false, vertical: true)
                }
            }
            .font(Fonts.font(11))
            .padding(.horizontal, 10)
            .padding(.vertical, 6)
            .frame(maxWidth: .infinity, alignment: .leading)
            .background(Palette.surface, in: RoundedRectangle(cornerRadius: 6))
            .padding(.vertical, 8)
        }
    }
}

private struct Attachments: View {
    let list: [Attachment]
    let taskId: String
    @Environment(Store.self) private var store

    var body: some View {
        if !list.isEmpty {
            VStack(alignment: .leading, spacing: 4) {
                ForEach(Array(list.enumerated()), id: \.offset) { _, a in
                    HStack(alignment: .firstTextBaseline, spacing: 6) {
                        Text("•")
                        VStack(alignment: .leading, spacing: 2) {
                            content(a)
                            if let caption = a.caption, !caption.isEmpty {
                                Text(caption).font(Fonts.font(11)).foregroundStyle(Palette.muted)
                            }
                        }
                    }
                }
            }
            .padding(.leading, 6)
            .padding(.vertical, 6)
        }
    }

    private func code(_ s: String) -> Text {
        Text(verbatim: s)
    }

    @ViewBuilder
    private func content(_ a: Attachment) -> some View {
        switch a.kind {
        case .file:
            let lines = a.startLine.map { ":\($0)\(a.endLine.map { "-\($0)" } ?? "")" } ?? ""
            code("\(a.path ?? "")\(lines)").textSelection(.enabled)
        case .diff:
            Text("diff \(code(a.ref ?? ""))").textSelection(.enabled)
        case .image:
            let src = (a.image?.isEmpty == false ? a.image : a.path) ?? ""
            let caption = a.caption ?? ""
            if let source = worktreeImageSource(src, taskId) {
                ByreImage(source: source, src: src)
            } else if !src.isEmpty {
                InlineView(inlines: [.link(href: src, [.text(caption.isEmpty ? src : caption)])], ctx: MDContext(taskId: taskId))
            }
        case .diagram:
            DiagramView(source: a.mermaid ?? "")
        case .task:
            let id = a.taskId ?? ""
            Button("task \(id)") {
                store.route("#/task/\(id)")
            }
            .buttonStyle(.plain)
            .foregroundStyle(store.taskColor(id) ?? Palette.accent)
        case .snapshot:
            Text("snapshot \(code(a.snapshotId ?? ""))").textSelection(.enabled)
        case .url:
            let url = a.url ?? ""
            if httpURL.test(url), let u = URL(string: url) {
                Link(url, destination: u).foregroundStyle(Palette.accent)
            } else {
                code(url).textSelection(.enabled)
            }
        }
    }
}