// Auteur : Simon-Pierre Boucher — contact@spboucher.ai
// SearchView.swift — la recherche UNIVERSELLE : une seule barre qui interroge
// tous les univers en parallèle (fan-out sur leurs API + web québécois via
// Trouve·Ka), résultats mélangés groupés par univers, filtres par univers,
// historique local.
import SwiftUI

struct SearchView: View {
    @State private var query = ""
    @State private var submitted = ""
    @State private var sections: [(universe: Universe, items: [KAItem])] = []
    @State private var searching = false
    @State private var selected: Set<String> = []       // filtres univers (vide = tous)
    @State private var sort: SortMode = .pertinence
    @State private var showSave = false
    @State private var saveName = ""
    @AppStorage("ka.search.history") private var historyRaw = ""
    @EnvironmentObject private var recents: RecentsStore
    @Environment(\.colorScheme) private var scheme

    enum SortMode: String, CaseIterable {
        case pertinence = "Pertinence"
        case prixAsc = "Prix ↑"
        case prixDesc = "Prix ↓"
    }

    private func sorted(_ items: [KAItem]) -> [KAItem] {
        switch sort {
        case .pertinence: return items
        case .prixAsc: return items.sorted { price($0) < price($1) }
        case .prixDesc: return items.sorted { price($0) > price($1) }
        }
    }
    private func price(_ i: KAItem) -> Double {
        Double(i.priceLabel?.filter { $0.isNumber } ?? "") ?? (sort == .prixAsc ? .greatestFiniteMagnitude : 0)
    }

    private var history: [String] { historyRaw.split(separator: "\n").map(String.init) }
    private var searchables: [Universe] { Ecosystem.all.filter { $0.map != nil } }

    var body: some View {
        NavigationStack {
            ScrollView {
                LazyVStack(alignment: .leading, spacing: 16) {
                    filterChips
                    if searching {
                        HStack(spacing: 10) {
                            ProgressView()
                            Text("KA interroge \(selected.isEmpty ? searchables.count : selected.count) univers…")
                                .font(.subheadline).foregroundStyle(.secondary)
                        }
                        .padding(24).frame(maxWidth: .infinity)
                    } else if submitted.isEmpty {
                        suggestions
                    } else if sections.allSatisfy({ $0.items.isEmpty }) {
                        KAEmptyState(symbol: "magnifyingglass", title: "Rien trouvé pour « \(submitted) »",
                                     message: "Essayez un autre mot, ou élargissez les univers filtrés.")
                    } else {
                        results
                    }
                }
                .padding(16)
            }
            .background(KATheme.paper(scheme))
            .navigationTitle("Recherche")
            .searchable(text: $query, prompt: "appartement Rouyn, resto italien, Corolla…")
            .onSubmit(of: .search) { Task { await search() } }
            .navigationDestination(for: KAItem.self) { ItemDetailView(item: $0) }
            .toolbar {
                if !submitted.isEmpty {
                    ToolbarItemGroup(placement: .topBarTrailing) {
                        Menu {
                            Picker("Tri", selection: $sort) {
                                ForEach(SortMode.allCases, id: \.self) { Text($0.rawValue).tag($0) }
                            }
                        } label: { Image(systemName: "arrow.up.arrow.down") }
                            .accessibilityLabel("Trier les résultats")
                        Button { saveName = submitted; showSave = true } label: {
                            Image(systemName: "bell.badge")
                        }
                        .accessibilityLabel("Sauvegarder cette recherche et créer une alerte")
                        ShareLink(item: URL(string: "https://www.trouve-ka.com/search?q=\(submitted.addingPercentEncoding(withAllowedCharacters: .urlQueryAllowed) ?? "")")!,
                                  subject: Text("Recherche KA : \(submitted)"))
                    }
                }
            }
            .alert("Sauvegarder la recherche", isPresented: $showSave) {
                TextField("Nom", text: $saveName)
                Button("Sauvegarder + alerte") {
                    let uid = selected.count == 1 ? selected.first! : (sections.max { $0.items.count < $1.items.count }?.universe.id ?? "lou-ka")
                    recents.saveSearch(name: saveName, universeID: uid, query: submitted, params: [:])
                }
                Button("Annuler", role: .cancel) {}
            } message: {
                Text("KA recomptera les résultats à chaque ouverture et vous montrera les nouveautés (+N).")
            }
        }
    }

    private var filterChips: some View {
        ScrollView(.horizontal, showsIndicators: false) {
            HStack(spacing: 8) {
                ForEach(searchables) { u in
                    let on = selected.isEmpty || selected.contains(u.id)
                    Button {
                        Haptics.tap()
                        if selected.contains(u.id) { selected.remove(u.id) }
                        else { selected.insert(u.id) }
                        if selected.count == searchables.count { selected = [] }
                        if !submitted.isEmpty { Task { await search(submitted) } }
                    } label: {
                        Text(u.wordmark)
                            .font(.system(.caption, design: .monospaced).weight(.bold))
                            .padding(.horizontal, 11).padding(.vertical, 7)
                            .background(on ? u.accent.opacity(0.9) : KATheme.surface(scheme), in: Capsule())
                            .foregroundStyle(on ? .white : .secondary)
                            .overlay(Capsule().strokeBorder(KATheme.ink(scheme).opacity(0.3), lineWidth: 1))
                    }
                    .accessibilityLabel("\(on ? "Masquer" : "Afficher") \(u.name)")
                }
            }
        }
    }

    private var suggestions: some View {
        VStack(alignment: .leading, spacing: 14) {
            if !history.isEmpty {
                Text("Récemment cherché").font(.headline)
                ForEach(history.prefix(6), id: \.self) { h in
                    Button {
                        query = h
                        Task { await search(h) }
                    } label: {
                        HStack {
                            Image(systemName: "clock.arrow.circlepath").foregroundStyle(.secondary)
                            Text(h)
                            Spacer()
                        }
                        .padding(12).kaCard()
                    }
                    .buttonStyle(.plain)
                }
            }
            Text("Idées").font(.headline)
            ForEach(["4½ à Québec", "resto italien Montréal", "Toyota Corolla", "emploi infirmière", "spectacle ce week-end"], id: \.self) { s in
                Button { query = s; Task { await search(s) } } label: {
                    HStack {
                        Image(systemName: "sparkle.magnifyingglass").foregroundStyle(KATheme.green)
                        Text(s); Spacer()
                    }
                    .padding(12).kaCard()
                }
                .buttonStyle(.plain)
            }
        }
    }

    private var results: some View {
        ForEach(sections.filter { !$0.items.isEmpty }, id: \.universe.id) { section in
            VStack(alignment: .leading, spacing: 10) {
                HStack {
                    KAWordmark(universe: section.universe, size: 16)
                    Spacer()
                    Text("\(section.items.count)")
                        .font(.system(.caption, design: .monospaced).weight(.bold))
                        .foregroundStyle(section.universe.accent)
                }
                ForEach(sorted(section.items).prefix(5)) { item in
                    NavigationLink(value: item) { KAItemRow(item: item) }
                        .buttonStyle(KAPressStyle())
                }
                NavigationLink(value: section.universe.id) {
                    Text("Tout voir dans \(section.universe.name) →")
                        .font(.subheadline.weight(.semibold))
                        .foregroundStyle(section.universe.accent)
                }
            }
        }
        .navigationDestination(for: String.self) { id in
            if let u = Ecosystem.universe(id) { UniverseHomeView(universe: u) }
        }
    }

    private func search(_ text: String? = nil) async {
        let q = (text ?? query).trimmingCharacters(in: .whitespaces)
        guard !q.isEmpty else { return }
        submitted = q
        searching = true
        Haptics.rigid()
        var hist = history.filter { $0 != q }
        hist.insert(q, at: 0)
        historyRaw = hist.prefix(10).joined(separator: "\n")

        let targets = searchables.filter { selected.isEmpty || selected.contains($0.id) }
        var found: [String: [KAItem]] = [:]
        await withTaskGroup(of: (String, [KAItem]).self) { group in
            for u in targets {
                group.addTask {
                    let items = (try? await UniverseService.fetch(u, query: q, limit: 8)) ?? []
                    return (u.id, items)
                }
            }
            for await (id, items) in group { found[id] = items }
        }
        // ordre : univers avec le plus de résultats d'abord, web québécois à la fin
        sections = targets
            .map { ($0, found[$0.id] ?? []) }
            .sorted {
                if $0.0.id == "trouve-ka" { return false }
                if $1.0.id == "trouve-ka" { return true }
                return $0.1.count > $1.1.count
            }
        searching = false
        if sections.contains(where: { !$0.items.isEmpty }) { Haptics.success() }
    }
}