//
//  ToolbarView.swift
//  Zyquo Atlas
//
//  Author: Simon-Pierre Boucher
//  Mail: contact@spboucher.ai
//
//  The unified browser toolbar: back / forward / reload-or-stop, the omnibox,
//  and a new-tab button. A determinate progress bar hairline sits under the
//  toolbar while a page loads. The AI panel toggle and profile switcher attach
//  here in later phases.
//

import SwiftUI

struct ToolbarView: View {
    @ObservedObject var tab: Tab
    let isAISidebarOpen: Bool
    let onSubmit: (String) -> Void
    let onNewTab: () -> Void
    let onToggleAI: () -> Void
    let onCustomize: () -> Void
    var downloadCount: Int = 0
    var onToggleDownloads: () -> Void = {}
    @EnvironmentObject private var themeEngine: ThemeEngine
    @EnvironmentObject private var windowState: WindowState
    private var theme: AtlasTheme { themeEngine.theme }

    var body: some View {
        VStack(spacing: 0) {
            HStack(spacing: ZyquoSpacing.xs) {
                navButton("chevron.backward", enabled: tab.canGoBack) { tab.goBack() }
                navButton("chevron.forward", enabled: tab.canGoForward) { tab.goForward() }
                if tab.isLoading {
                    navButton("xmark", enabled: true) { tab.stop() }
                } else {
                    navButton("arrow.clockwise", enabled: tab.url != nil) { tab.reload() }
                }
                readerButton

                OmniboxView(tab: tab, onSubmit: onSubmit,
                            onAsk: { windowState.askOmnibox($0) })
                    .frame(maxWidth: .infinity)

                navButton("plus", enabled: true, action: onNewTab)
                downloadsButton
                navButton("paintbrush", enabled: true, action: onCustomize)
                aiToggle
            }
            .padding(.horizontal, ZyquoSpacing.sm)
            .frame(height: themeEngine.layout.toolbarHeight)

            progressBar
        }
        .background(theme.surface)
        .overlay(alignment: .bottom) {
            Rectangle()
                .fill(theme.border)
                .frame(height: ZyquoMetrics.hairline)
        }
    }

    // MARK: - Progress

    @ViewBuilder
    private var progressBar: some View {
        GeometryReader { geo in
            if tab.showsProgress {
                Rectangle()
                    .fill(theme.accent)
                    .frame(width: geo.size.width * max(0.02, tab.estimatedProgress))
                    .animation(.easeOut(duration: 0.2), value: tab.estimatedProgress)
            }
        }
        .frame(height: 2)
    }

    private var readerButton: some View {
        Button { windowState.toggleReader() } label: {
            Image(systemName: windowState.showReader ? "doc.plaintext.fill" : "doc.plaintext")
                .font(.system(size: 13, weight: .medium))
                .frame(width: 28, height: 28)
                .contentShape(Rectangle())
        }
        .buttonStyle(.plain)
        .foregroundStyle(windowState.showReader ? theme.accent : theme.textSecondary)
        .disabled(tab.url == nil)
        .help("Reader mode")
    }

    private var downloadsButton: some View {
        Button(action: onToggleDownloads) {
            Image(systemName: "arrow.down.circle")
                .font(.system(size: 13, weight: .medium))
                .frame(width: 28, height: 28)
                .contentShape(Rectangle())
                .overlay(alignment: .topTrailing) {
                    if downloadCount > 0 {
                        Circle().fill(theme.accent).frame(width: 8, height: 8).offset(x: -4, y: 4)
                    }
                }
        }
        .buttonStyle(.plain)
        .foregroundStyle(theme.textSecondary)
        .help("Downloads")
    }

    private var aiToggle: some View {
        Button(action: onToggleAI) {
            Image(systemName: "sparkles")
                .font(.system(size: 13, weight: .medium))
                .frame(width: 28, height: 28)
                .contentShape(Rectangle())
        }
        .buttonStyle(.plain)
        .foregroundStyle(isAISidebarOpen ? theme.accentIndigo : theme.textSecondary)
        .help("Toggle Atlas AI sidebar")
    }

    // MARK: - Buttons

    private func navButton(_ symbol: String, enabled: Bool, action: @escaping () -> Void) -> some View {
        Button(action: action) {
            Image(systemName: symbol)
                .font(.system(size: 13, weight: .medium))
                .frame(width: 28, height: 28)
                .contentShape(Rectangle())
        }
        .buttonStyle(.plain)
        .foregroundStyle(enabled ? theme.textSecondary : theme.textTertiary.opacity(0.5))
        .disabled(!enabled)
    }
}