// Auteur : Simon-Pierre Boucher — contact@spboucher.ai
// UniverseExplorerView.swift — l'explorateur premium d'un univers : héros
// (wordmark, tagline, compteur live, lien site), recherche + FILTRES MÉTIER,
// grille photo multi-colonnes (grandes fenêtres) ou liste, fiche détaillée
// riche (galerie, faits, description, liens, menu resto), sauvegarde de la
// recherche avec alerte. Vrai-Prix a son expérience NATIVE (search+estimate).
// Adapté de l'app iOS KA (UniversesView.swift + VraiPrixView.swift).
import SwiftUI

struct UniverseExplorerView: View {
    let universe: Universe
    @EnvironmentObject private var pulse: EcosystemPulse
    @EnvironmentObject private var state: AppState
    @EnvironmentObject private var recents: RecentsStore
    @Environment(\.colorScheme) private var scheme

    @State private var items: [KAItem] = []
    @State private var selected: KAItem?
    @State private var query = ""
    @State private var filterParams: [String: String] = [:]
    @State private var loading = true
    @State private var errorText: String?
    @State private var asGrid = true
    @State private var savedFlash = false
    /// Bascule Données (explorateur natif) | Site (le vrai site web, intégré).
    enum Mode: String, CaseIterable { case donnees = "Données", site = "Site" }
    @State private var mode: Mode

    init(universe: Universe) {
        self.universe = universe
        // Les univers sans liste native s'ouvrent directement sur leur site.
        let nativeless = universe.listPath == nil || universe.map == nil
        let hasCustom = universe.id == "vrai-prix" || universe.id == "api-ka"
        _mode = State(initialValue: nativeless && !hasCustom ? .site : .donnees)
    }

    var body: some View {
        Group {
            if mode == .site {
                SiteView(universe: universe)
            } else if universe.id == "vrai-prix" {
                VraiPrixExplorer(universe: universe)
            } else if universe.id == "api-ka" {
                ApiPlaygroundView(universe: universe)
            } else if universe.listPath == nil || universe.map == nil {
                SiteView(universe: universe)
            } else {
                explorer
            }
        }
        .toolbar {
            ToolbarItem(placement: .principal) {
                Picker("Présentation de \(universe.name)", selection: $mode) {
                    ForEach(Mode.allCases, id: \.self) { m in
                        Text(m.rawValue).tag(m)
                    }
                }
                .pickerStyle(.segmented)
                .labelsHidden()
                .frame(width: 170)
                .help("Données = explorateur natif ; Site = le site web \(universe.domain), intégré")
            }
        }
    }

    // MARK: explorateur grille/liste + fiche

    private var explorer: some View {
        VStack(spacing: 0) {
            hero
            Divider().opacity(0.4)
            HStack(spacing: 0) {
                results
                    .frame(maxWidth: .infinity)
                Divider().opacity(0.4)
                Group {
                    if let item = selected {
                        ItemDetailPane(item: item)
                    } else {
                        KAEmptyState(symbol: universe.symbol,
                                     title: "Choisissez un élément",
                                     message: "La fiche détaillée s'affichera ici.")
                            .frame(maxHeight: .infinity)
                            .background(KATheme.paper(scheme))
                    }
                }
                .frame(width: 440)
            }
        }
        .task {
            consumePrefill()
            await load()
        }
        .onChange(of: state.prefill?.universeID) {
            if state.prefill?.universeID == universe.id {
                consumePrefill()
                Task { await load() }
            }
        }
    }

    private var hero: some View {
        VStack(alignment: .leading, spacing: 12) {
            SiteHero(universe: universe, liveTotal: pulse.totals[universe.id]) { mode = .site }
            HStack(spacing: 8) {
                Picker("Présentation", selection: $asGrid) {
                    Image(systemName: "square.grid.2x2").tag(true)
                    Image(systemName: "list.bullet").tag(false)
                }
                .pickerStyle(.segmented)
                .labelsHidden()
                .frame(width: 90)
                KASearchField(prompt: "Chercher dans \(universe.name)…", text: $query) {
                    Task { await load() }
                }
                FilterBar(universe: universe, params: $filterParams) {
                    Task { await load() }
                }
                if !query.isEmpty || !filterParams.isEmpty {
                    Button {
                        recents.saveSearch(name: "", universeID: universe.id,
                                           query: query, params: filterParams)
                        savedFlash = true
                        Task { try? await Task.sleep(for: .seconds(2)); savedFlash = false }
                    } label: {
                        Label(savedFlash ? "Alerte créée ✓" : "Sauvegarder + alerte",
                              systemImage: savedFlash ? "bell.badge.fill" : "bell.badge")
                            .font(.caption.weight(.bold))
                            .padding(.horizontal, 10).padding(.vertical, 7)
                            .background(savedFlash ? KATheme.green : universe.accent, in: Capsule())
                            .foregroundStyle(.white)
                    }
                    .buttonStyle(.plain)
                    .help("Sauvegarder cette recherche — KA recompte le total à chaque ouverture et signale les nouveautés")
                }
            }
        }
        .padding(.horizontal, 16).padding(.vertical, 12)
    }

    @ViewBuilder
    private var results: some View {
        ScrollView {
            Group {
                if universe.id == "trouve-ka" && query.isEmpty {
                    KAEmptyState(symbol: "magnifyingglass",
                                 title: "Cherchez le web québécois",
                                 message: "Trouve·Ka fouille \(pulse.totals[universe.id].map { $0.fr } ?? "plus d'un million de") pages indexées — tapez un mot-clé ci-dessus.")
                } else if loading {
                    LazyVStack(spacing: 10) {
                        ForEach(0..<6, id: \.self) { _ in KASkeletonRow() }
                    }
                } else if let e = errorText, items.isEmpty {
                    KAEmptyState(symbol: "wifi.exclamationmark", title: "Impossible de charger", message: e)
                } else if items.isEmpty {
                    KAEmptyState(symbol: "tray", title: "Aucun résultat",
                                 message: "Essayez d'autres mots-clés ou élargissez les filtres.")
                } else if asGrid {
                    LazyVGrid(columns: [GridItem(.adaptive(minimum: 230), spacing: 12)], spacing: 12) {
                        ForEach(items) { item in
                            Button { selected = item } label: {
                                KAItemCard(item: item, selected: selected?.id == item.id)
                            }
                            .buttonStyle(KAPressStyle())
                        }
                    }
                } else {
                    LazyVStack(spacing: 10) {
                        ForEach(items) { item in
                            Button { selected = item } label: {
                                KAItemRow(item: item)
                                    .overlay(
                                        RoundedRectangle(cornerRadius: 10, style: .continuous)
                                            .strokeBorder(universe.accent,
                                                          lineWidth: selected?.id == item.id ? 2.4 : 0)
                                            .padding(.trailing, 6).padding(.bottom, 6)
                                    )
                            }
                            .buttonStyle(KAPressStyle())
                        }
                    }
                }
            }
            .padding(14)
            .animation(.snappy(duration: 0.3), value: items)
        }
        .background(KATheme.paper(scheme))
    }

    private func consumePrefill() {
        if let p = state.prefill, p.universeID == universe.id {
            query = p.query
            filterParams = p.params
            state.prefill = nil
        }
    }

    private func load() async {
        // Trouve·Ka est un moteur : pas de liste sans requête
        if universe.id == "trouve-ka" && query.isEmpty {
            items = []; selected = nil; loading = false; errorText = nil
            return
        }
        loading = items.isEmpty
        errorText = nil
        do {
            // Trouve·Ka (FastAPI) plafonne limit à 50 — 422 au-delà
            let cap = universe.id == "trouve-ka" ? 50 : 60
            items = try await UniverseService.fetch(universe, query: query.isEmpty ? nil : query,
                                                    limit: cap, params: filterParams)
            if let sel = selected, !items.contains(where: { $0.id == sel.id }) { selected = nil }
            if selected == nil { selected = items.first }
        } catch {
            errorText = (error as? URLError)?.code == .notConnectedToInternet
                ? "Vous êtes hors ligne." : "Le service ne répond pas."
        }
        loading = false
    }
}

// MARK: - Héros de site (reproduction fidèle de la page d'accueil de l'univers)
// Spec : app iOS KA (UniversesView.swift, struct SiteHero) — adapté desktop.

struct SiteHero: View {
    let universe: Universe
    let liveTotal: Int?
    var openSite: (() -> Void)? = nil
    @Environment(\.colorScheme) private var scheme

    private var copy: HeroCopy? { KAHeroes.hero(universe.id) }

    var body: some View {
        VStack(alignment: .leading, spacing: 10) {
            ticker
            if let c = copy {
                if let k = c.kicker {
                    HStack(spacing: 10) {
                        Rectangle().fill(KATheme.green).frame(width: 26, height: 2.5)
                        Text(k.uppercased())
                            .font(KAFont.mono(10))
                            .foregroundStyle(scheme == .dark ? KATheme.lime : KATheme.green)
                            .kerning(1.1)
                            .lineLimit(1)
                    }
                }
                HStack(alignment: .top, spacing: 18) {
                    VStack(alignment: .leading, spacing: 7) {
                        headline(c)
                        Text(c.sub)
                            .font(.subheadline)
                            .foregroundStyle(KATheme.ink2(scheme))
                            .lineLimit(3)
                    }
                    Spacer(minLength: 0)
                    VStack(alignment: .trailing, spacing: 9) {
                        statPill
                        if let openSite {
                            Button(action: openSite) {
                                Text("VOIR LE SITE ↗")
                                    .font(KAFont.mono(10))
                                    .foregroundStyle(universe.accent)
                                    .padding(.horizontal, 12).padding(.vertical, 8)
                                    .background(KATheme.inkLight, in: RoundedRectangle(cornerRadius: 6, style: .continuous))
                            }
                            .buttonStyle(KAPressStyle())
                            .help("Ouvrir \(universe.domain) dans l'app")
                            .accessibilityLabel("Voir le site \(universe.name) dans l'app")
                        }
                    }
                }
            }
        }
    }

    /// Bandeau ticker encre — la signature du haut des sites
    private var ticker: some View {
        HStack(spacing: 9) {
            KALogo(id: universe.id, size: 18,
                   fallbackSymbol: universe.symbol, fallbackAccent: universe.accent)
            Text(universe.unit.uppercased())
                .font(KAFont.mono(9.5))
                .foregroundStyle(.white.opacity(0.9))
            Text("◆").font(KAFont.mono(8)).foregroundStyle(universe.accent)
            Text("EN DIRECT")
                .font(KAFont.mono(9.5))
                .foregroundStyle(universe.accent)
            Text("◆").font(KAFont.mono(8)).foregroundStyle(universe.accent)
            Text(universe.domain.replacingOccurrences(of: "www.", with: "").uppercased())
                .font(KAFont.mono(9.5))
                .foregroundStyle(.white.opacity(0.75))
                .lineLimit(1)
            Text("◆").font(KAFont.mono(8)).foregroundStyle(universe.accent)
            Text(universe.tagline.uppercased())
                .font(KAFont.mono(9.5))
                .foregroundStyle(.white.opacity(0.6))
                .lineLimit(1)
            Spacer(minLength: 0)
        }
        .padding(.horizontal, 12).padding(.vertical, 8)
        .background(KATheme.inkLight, in: RoundedRectangle(cornerRadius: 8, style: .continuous))
    }

    /// Titre display avec le segment surligné SUR l'accent (comme le h1 du site)
    private func headline(_ c: HeroCopy) -> some View {
        var attr = AttributedString(c.headline)
        attr.font = KAFont.display(24)
        attr.foregroundColor = KATheme.ink(scheme)
        if let hl = c.highlight,
           let range = attr.range(of: hl, options: .caseInsensitive) {
            attr[range].backgroundColor = universe.accent
            attr[range].foregroundColor = .white
        }
        return Text(attr).lineSpacing(2)
    }

    private var statPill: some View {
        HStack(spacing: 7) {
            Circle().fill(universe.accent).frame(width: 8, height: 8)
            if let n = liveTotal {
                Text(n.fr)
                    .font(KAFont.display(14))
                    .contentTransition(.numericText())
                Text(universe.unit)
                    .font(.caption).foregroundStyle(KATheme.ink2(scheme))
            } else {
                Text("En direct").font(.caption).foregroundStyle(KATheme.ink2(scheme))
            }
        }
        .padding(.horizontal, 12).padding(.vertical, 7)
        .background(KATheme.surface(scheme), in: Capsule())
        .overlay(Capsule().strokeBorder(KATheme.ink(scheme).opacity(scheme == .dark ? 0.35 : 0.85), lineWidth: 1.5))
        .background(Capsule().fill(scheme == .dark ? Color.clear : KATheme.inkLight).offset(x: 4, y: 4))
        .padding(.trailing, 4).padding(.bottom, 4)
    }
}

// MARK: - Fiche universelle (panneau de droite)

struct ItemDetailPane: View {
    let item: KAItem
    @Environment(\.colorScheme) private var scheme
    @EnvironmentObject private var favorites: FavoritesStore
    @EnvironmentObject private var recents: RecentsStore
    @State private var galleryIndex = 0
    @State private var menu: [RestoMenuSection] = []

    private var universe: Universe? { Ecosystem.universe(item.universeID) }

    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 16) {
                gallery
                HStack {
                    if let u = universe { KAChip(text: u.wordmark, accent: u.accent) }
                    Spacer()
                    if favorites.collections.count > 1 && !favorites.isFavorite(item) {
                        Menu {
                            ForEach(favorites.collections) { c in
                                Button(c.name) { favorites.toggle(item, in: c.id) }
                            }
                        } label: {
                            Image(systemName: "heart")
                        }
                        .menuStyle(.borderlessButton)
                        .fixedSize()
                        .help("Ajouter à une collection")
                    } else {
                        Button {
                            favorites.toggle(item)
                        } label: {
                            Image(systemName: favorites.isFavorite(item) ? "heart.fill" : "heart")
                                .foregroundStyle(favorites.isFavorite(item) ? .red : .primary)
                        }
                        .buttonStyle(.plain)
                        .help(favorites.isFavorite(item) ? "Retirer des favoris" : "Ajouter aux favoris")
                    }
                    if let url = item.url {
                        ShareLink(item: url, subject: Text(item.title)) {
                            Image(systemName: "square.and.arrow.up")
                        }
                        .buttonStyle(.plain)
                        .help("Partager le lien")
                    }
                }
                .font(.title3)
                Text(item.title).font(.title2.weight(.bold)).textSelection(.enabled)
                if let sub = item.subtitle, !sub.isEmpty {
                    Text(sub).font(.body).foregroundStyle(KATheme.ink2(scheme)).textSelection(.enabled)
                }
                HStack(spacing: 10) {
                    if let p = item.priceLabel {
                        Text(p).font(.system(.title3, design: .rounded).weight(.bold))
                            .foregroundStyle(universe?.accent ?? .primary)
                    }
                    if let c = item.city, !c.isEmpty { KAChip(text: c) }
                }

                if let detail = item.detail, !detail.isEmpty {
                    VStack(alignment: .leading, spacing: 6) {
                        Text("À propos").font(.headline)
                        Text(detail)
                            .font(.subheadline)
                            .foregroundStyle(KATheme.ink2(scheme))
                            .textSelection(.enabled)
                    }
                    .padding(14)
                    .frame(maxWidth: .infinity, alignment: .leading)
                    .kaCard()
                }

                if !item.facts.isEmpty {
                    VStack(spacing: 0) {
                        ForEach(item.facts, id: \.self) { f in
                            HStack(alignment: .top) {
                                Text(f.label).font(.subheadline).foregroundStyle(.secondary)
                                Spacer()
                                Text(f.value).font(.subheadline.weight(.semibold))
                                    .multilineTextAlignment(.trailing)
                                    .textSelection(.enabled)
                            }
                            .padding(.vertical, 9).padding(.horizontal, 14)
                            if f != item.facts.last { Divider() }
                        }
                    }
                    .kaCard()
                }

                if !item.links.isEmpty {
                    VStack(alignment: .leading, spacing: 8) {
                        Text("Comptes & liens").font(.headline)
                        ForEach(item.links, id: \.self) { l in
                            if let u = URL(string: l.value) {
                                Link(destination: u) {
                                    HStack {
                                        Image(systemName: "link")
                                        Text(l.label).font(.subheadline.weight(.semibold))
                                        Spacer()
                                        Image(systemName: "arrow.up.right").font(.caption)
                                    }
                                    .padding(11)
                                    .background((universe?.accent ?? .gray).opacity(0.1),
                                                in: RoundedRectangle(cornerRadius: 10, style: .continuous))
                                }
                                .foregroundStyle(universe?.accent ?? .primary)
                            }
                        }
                    }
                }

                if !menu.isEmpty {
                    VStack(alignment: .leading, spacing: 10) {
                        HStack {
                            Text("Menu & prix réels").font(.headline)
                            Spacer()
                            KAChip(text: "\(menu.reduce(0) { $0 + $1.items.count }) plats", accent: universe?.accent)
                        }
                        ForEach(menu.prefix(8)) { section in
                            DisclosureGroup {
                                VStack(spacing: 0) {
                                    ForEach(section.items, id: \.name) { dish in
                                        HStack(alignment: .top) {
                                            Text(dish.name).font(.subheadline)
                                            Spacer()
                                            if let p = dish.price {
                                                Text(p).font(.system(.subheadline, design: .rounded).weight(.bold))
                                                    .foregroundStyle(universe?.accent ?? .primary)
                                            }
                                        }
                                        .padding(.vertical, 6)
                                        Divider().opacity(dish.name == section.items.last?.name ? 0 : 0.6)
                                    }
                                }
                                .padding(.top, 4)
                            } label: {
                                Text(section.name).font(.subheadline.weight(.bold))
                            }
                            .padding(.horizontal, 14).padding(.vertical, 8)
                            .kaCard()
                        }
                    }
                }

                if let url = item.url {
                    Link(destination: url) {
                        Label("Voir à la source", systemImage: "arrow.up.right.square")
                            .font(.headline)
                            .frame(maxWidth: .infinity).padding(.vertical, 13)
                            .background(universe?.accent ?? KATheme.green,
                                        in: RoundedRectangle(cornerRadius: 11, style: .continuous))
                            .foregroundStyle(.white)
                    }
                    .buttonStyle(.plain)
                    Text("Groupe KA est un agrégateur : la transaction se fait chez la source originale.")
                        .font(.caption2).foregroundStyle(.tertiary)
                }
            }
            .padding(18)
        }
        .background(KATheme.paper(scheme))
        .task(id: item.id) {
            galleryIndex = 0
            menu = []
            recents.record(item) // historique consulté
            if item.universeID == "resto-ka" {
                let uid = String(item.id.dropFirst("resto-ka:".count))
                menu = await RestoMenuLoader.load(uid: uid)
            }
        }
    }

    // MARK: galerie (image principale + vignettes cliquables)

    @ViewBuilder
    private var gallery: some View {
        if !item.imageURLs.isEmpty {
            VStack(spacing: 8) {
                ZStack(alignment: .bottomTrailing) {
                    KAImage(url: item.imageURLs[min(galleryIndex, item.imageURLs.count - 1)],
                            accent: universe?.accent ?? .gray, symbol: universe?.symbol ?? "photo")
                        .frame(maxWidth: .infinity)
                        .frame(height: 250)
                        .clipShape(RoundedRectangle(cornerRadius: 14, style: .continuous))
                        .overlay(RoundedRectangle(cornerRadius: 14, style: .continuous)
                            .strokeBorder(.primary.opacity(0.3), lineWidth: 1.2))
                        .accessibilityLabel("Photo \(galleryIndex + 1) sur \(item.imageURLs.count) : \(item.title)")
                    if item.imageURLs.count > 1 {
                        Text("\(galleryIndex + 1)/\(item.imageURLs.count)")
                            .font(.system(.caption2, design: .monospaced).weight(.bold))
                            .padding(.horizontal, 8).padding(.vertical, 4)
                            .background(.ultraThinMaterial, in: Capsule())
                            .padding(8)
                    }
                }
                if item.imageURLs.count > 1 {
                    ScrollView(.horizontal, showsIndicators: false) {
                        HStack(spacing: 6) {
                            ForEach(Array(item.imageURLs.enumerated()), id: \.offset) { i, url in
                                Button { galleryIndex = i } label: {
                                    KAImage(url: url, accent: universe?.accent ?? .gray)
                                        .frame(width: 64, height: 44)
                                        .clipShape(RoundedRectangle(cornerRadius: 7, style: .continuous))
                                        .overlay(RoundedRectangle(cornerRadius: 7, style: .continuous)
                                            .strokeBorder(i == galleryIndex ? (universe?.accent ?? .blue) : .primary.opacity(0.2),
                                                          lineWidth: i == galleryIndex ? 2.2 : 1))
                                }
                                .buttonStyle(.plain)
                                .accessibilityLabel("Photo \(i + 1)")
                            }
                        }
                        .padding(2)
                    }
                }
            }
        }
    }
}