//
//  CommandPaletteView.swift
//  Zyquo Cloud
//
//  Author: Simon-Pierre Boucher
//  Mail: contact@spboucher.ai
//
//  ⌘K palette: one search box over models, prompt templates, and personas.
//  Models switch the current conversation; templates insert into the draft;
//  personas apply their system prompt + preferences.
//

import SwiftUI

struct CommandPaletteView: View {
    let currentModel: AIModel?
    var onSelectModel: (AIModel) -> Void
    var onInsertTemplate: (PromptTemplate) -> Void
    var onApplyPersona: (Persona) -> Void

    @EnvironmentObject private var catalog: ModelCatalog
    @StateObject private var library = PromptLibraryStore()
    @Environment(\.dismiss) private var dismiss
    @State private var query = ""
    @FocusState private var focused: Bool

    var body: some View {
        VStack(spacing: 0) {
            HStack(spacing: ZyquoSpacing.xs) {
                Image(systemName: "command")
                    .font(.system(size: 13))
                    .foregroundStyle(ZyquoColor.textTertiary)
                TextField("Switch model, insert template, apply persona…", text: $query)
                    .textFieldStyle(.plain)
                    .font(ZyquoFont.body(size: 15))
                    .focused($focused)
            }
            .padding(ZyquoSpacing.md)
            ZyquoHairline()
            ScrollView {
                LazyVStack(alignment: .leading, spacing: 1) {
                    if !matchingModels.isEmpty {
                        section("Models")
                        ForEach(matchingModels.prefix(8)) { model in
                            paletteRow(
                                symbol: model.provider.symbolName,
                                title: model.displayName,
                                subtitle: "\(model.provider.displayName) · \(model.contextBadge)"
                            ) {
                                onSelectModel(model)
                                dismiss()
                            }
                        }
                    }
                    if !matchingPersonas.isEmpty {
                        section("Personas")
                        ForEach(matchingPersonas.prefix(6)) { persona in
                            paletteRow(
                                symbol: persona.symbolName,
                                title: persona.name,
                                subtitle: String(persona.systemPrompt.prefix(70))
                            ) {
                                onApplyPersona(persona)
                                dismiss()
                            }
                        }
                    }
                    if !matchingTemplates.isEmpty {
                        section("Prompt Library")
                        ForEach(matchingTemplates.prefix(10)) { template in
                            paletteRow(
                                symbol: "text.badge.plus",
                                title: template.title,
                                subtitle: template.category
                            ) {
                                onInsertTemplate(template)
                                dismiss()
                            }
                        }
                    }
                }
                .padding(ZyquoSpacing.xxs)
            }
            .frame(height: 380)
        }
        .frame(width: 560)
        .background(ZyquoColor.surface)
        .onAppear { focused = true }
        .onExitCommand { dismiss() }
    }

    private var matchingModels: [AIModel] {
        query.isEmpty
            ? catalog.all.filter(\.isRecommended)
            : catalog.all.filter {
                $0.displayName.localizedCaseInsensitiveContains(query)
                    || $0.id.localizedCaseInsensitiveContains(query)
            }
    }

    private var matchingTemplates: [PromptTemplate] {
        query.isEmpty
            ? Array(library.allTemplates.prefix(10))
            : library.allTemplates.filter {
                $0.title.localizedCaseInsensitiveContains(query)
                    || $0.category.localizedCaseInsensitiveContains(query)
            }
    }

    private var matchingPersonas: [Persona] {
        query.isEmpty
            ? library.allPersonas
            : library.allPersonas.filter { $0.name.localizedCaseInsensitiveContains(query) }
    }

    private func section(_ title: String) -> some View {
        Text(title)
            .font(ZyquoFont.caption)
            .foregroundStyle(ZyquoColor.textTertiary)
            .padding(.horizontal, ZyquoSpacing.sm)
            .padding(.top, ZyquoSpacing.xs)
            .padding(.bottom, 2)
    }

    private func paletteRow(
        symbol: String, title: String, subtitle: String, action: @escaping () -> Void
    ) -> some View {
        Button(action: action) {
            HStack(spacing: ZyquoSpacing.sm) {
                Image(systemName: symbol)
                    .font(.system(size: 13))
                    .foregroundStyle(ZyquoColor.accent)
                    .frame(width: 18)
                VStack(alignment: .leading, spacing: 0) {
                    Text(title)
                        .font(ZyquoFont.body(size: 13))
                        .foregroundStyle(ZyquoColor.textPrimary)
                    Text(subtitle)
                        .font(ZyquoFont.caption)
                        .foregroundStyle(ZyquoColor.textTertiary)
                        .lineLimit(1)
                }
                Spacer()
            }
            .padding(.horizontal, ZyquoSpacing.sm)
            .padding(.vertical, 5)
            .contentShape(Rectangle())
        }
        .buttonStyle(.plain)
        .zyquoHoverHighlight()
    }
}