import Cocoa

class MainWindowController: NSWindowController {
    var tabManager = TabManager()
    var tabBar: NSStackView!
    var contentView: NSView!
    var currentSessionView: NSScrollView?
    
    convenience init() {
        let window = NSWindow(
            contentRect: NSRect(x: 0, y: 0, width: 1000, height: 700),
            styleMask: [.titled, .closable, .miniaturizable, .resizable, .fullSizeContentView],
            backing: .buffered,
            defer: false
        )
        window.titlebarAppearsTransparent = true
        window.titleVisibility = .hidden
        window.center()
        window.title = "Enhanced Terminal"
        window.isReleasedWhenClosed = false
        
        self.init(window: window)
        setupUI()
        addNewTab()
        
        // Force window to show
        window.makeKeyAndOrderFront(nil)
        window.orderFrontRegardless()
    }
    
    private func setupUI() {
        guard let window = window else { return }
        
        let mainContainer = NSView(frame: window.contentView!.bounds)
        mainContainer.autoresizingMask = [.width, .height]
        
        // Tab bar
        tabBar = NSStackView(frame: NSRect(x: 0, y: mainContainer.bounds.height - 40, width: mainContainer.bounds.width, height: 40))
        tabBar.orientation = .horizontal
        tabBar.distribution = .fillProportionally
        tabBar.spacing = 0
        tabBar.autoresizingMask = [.width, .minYMargin]
        tabBar.wantsLayer = true
        tabBar.layer?.backgroundColor = NSColor(white: 0.15, alpha: 1.0).cgColor
        
        // Content view
        contentView = NSView(frame: NSRect(x: 0, y: 0, width: mainContainer.bounds.width, height: mainContainer.bounds.height - 40))
        contentView.autoresizingMask = [.width, .height]
        
        mainContainer.addSubview(contentView)
        mainContainer.addSubview(tabBar)
        
        window.contentView = mainContainer
        
        setupMenuBar()
    }
    
    private func setupMenuBar() {
        let mainMenu = NSMenu()
        
        // App menu
        let appMenuItem = NSMenuItem()
        mainMenu.addItem(appMenuItem)
        let appMenu = NSMenu()
        appMenuItem.submenu = appMenu
        
        appMenu.addItem(NSMenuItem(title: "Settings...", action: #selector(openSettings), keyEquivalent: ","))
        appMenu.addItem(NSMenuItem.separator())
        appMenu.addItem(NSMenuItem(title: "Quit", action: #selector(NSApplication.terminate(_:)), keyEquivalent: "q"))
        
        // File menu
        let fileMenuItem = NSMenuItem(title: "File", action: nil, keyEquivalent: "")
        mainMenu.addItem(fileMenuItem)
        let fileMenu = NSMenu(title: "File")
        fileMenuItem.submenu = fileMenu
        
        fileMenu.addItem(NSMenuItem(title: "New Tab", action: #selector(addNewTab), keyEquivalent: "t"))
        fileMenu.addItem(NSMenuItem(title: "Close Tab", action: #selector(closeCurrentTab), keyEquivalent: "w"))
        fileMenu.addItem(NSMenuItem.separator())
        fileMenu.addItem(NSMenuItem(title: "Split Vertically", action: #selector(splitVertically), keyEquivalent: "d"))
        
        let splitHorizontal = NSMenuItem(title: "Split Horizontally", action: #selector(splitHorizontally), keyEquivalent: "d")
        splitHorizontal.keyEquivalentModifierMask = [.command, .shift]
        fileMenu.addItem(splitHorizontal)
        
        // Edit menu
        let editMenuItem = NSMenuItem(title: "Edit", action: nil, keyEquivalent: "")
        mainMenu.addItem(editMenuItem)
        let editMenu = NSMenu(title: "Edit")
        editMenuItem.submenu = editMenu
        
        editMenu.addItem(NSMenuItem(title: "Copy", action: #selector(NSText.copy(_:)), keyEquivalent: "c"))
        editMenu.addItem(NSMenuItem(title: "Paste", action: #selector(NSText.paste(_:)), keyEquivalent: "v"))
        editMenu.addItem(NSMenuItem(title: "Select All", action: #selector(NSText.selectAll(_:)), keyEquivalent: "a"))
        editMenu.addItem(NSMenuItem.separator())
        editMenu.addItem(NSMenuItem(title: "Search History", action: #selector(searchHistory), keyEquivalent: "r"))
        
        // View menu
        let viewMenuItem = NSMenuItem(title: "View", action: nil, keyEquivalent: "")
        mainMenu.addItem(viewMenuItem)
        let viewMenu = NSMenu(title: "View")
        viewMenuItem.submenu = viewMenu
        
        viewMenu.addItem(NSMenuItem(title: "Toggle Fullscreen", action: #selector(NSWindow.toggleFullScreen(_:)), keyEquivalent: "f"))
        viewMenu.addItem(NSMenuItem(title: "Increase Font Size", action: #selector(increaseFontSize), keyEquivalent: "+"))
        viewMenu.addItem(NSMenuItem(title: "Decrease Font Size", action: #selector(decreaseFontSize), keyEquivalent: "-"))
        
        // Tools menu
        let toolsMenuItem = NSMenuItem(title: "Tools", action: nil, keyEquivalent: "")
        mainMenu.addItem(toolsMenuItem)
        let toolsMenu = NSMenu(title: "Tools")
        toolsMenuItem.submenu = toolsMenu
        
        toolsMenu.addItem(NSMenuItem(title: "AI Command Generator", action: #selector(showAIGenerator), keyEquivalent: "k"))
        toolsMenu.addItem(NSMenuItem(title: "Snippets", action: #selector(showSnippets), keyEquivalent: "p"))
        toolsMenu.addItem(NSMenuItem(title: "Command Palette", action: #selector(showCommandPalette), keyEquivalent: "p"))
        
        NSApp.mainMenu = mainMenu
    }
    
    @objc func addNewTab() {
        let session = tabManager.addTab()
        session.setupTextView(frame: contentView.bounds)
        session.startShell()
        
        updateTabBar()
        switchToTab(index: tabManager.tabs.count - 1)
    }
    
    @objc func closeCurrentTab() {
        guard tabManager.tabs.count > 1 else {
            NSApp.terminate(nil)
            return
        }
        
        tabManager.removeTab(at: tabManager.currentIndex)
        updateTabBar()
        switchToTab(index: tabManager.currentIndex)
    }
    
    private func updateTabBar() {
        tabBar.arrangedSubviews.forEach { $0.removeFromSuperview() }
        
        for (index, session) in tabManager.tabs.enumerated() {
            let tabButton = NSButton(frame: NSRect(x: 0, y: 0, width: 150, height: 40))
            tabButton.title = session.title
            tabButton.bezelStyle = .rounded
            tabButton.tag = index
            tabButton.target = self
            tabButton.action = #selector(tabClicked(_:))
            
            if index == tabManager.currentIndex {
                tabButton.contentTintColor = .systemBlue
            }
            
            tabBar.addArrangedSubview(tabButton)
        }
        
        // Add new tab button
        let newTabButton = NSButton(frame: NSRect(x: 0, y: 0, width: 40, height: 40))
        newTabButton.title = "+"
        newTabButton.bezelStyle = .rounded
        newTabButton.target = self
        newTabButton.action = #selector(addNewTab)
        tabBar.addArrangedSubview(newTabButton)
    }
    
    @objc func tabClicked(_ sender: NSButton) {
        switchToTab(index: sender.tag)
    }
    
    private func switchToTab(index: Int) {
        guard index < tabManager.tabs.count else { return }
        
        tabManager.selectTab(at: index)
        
        contentView.subviews.forEach { $0.removeFromSuperview() }
        
        if let session = tabManager.getCurrentSession(),
           let scrollView = session.textView.enclosingScrollView {
            scrollView.frame = contentView.bounds
            contentView.addSubview(scrollView)
            currentSessionView = scrollView
        }
        
        updateTabBar()
    }
    
    @objc func splitVertically() {
        showAlert("Split panes feature coming soon!")
    }
    
    @objc func splitHorizontally() {
        showAlert("Split panes feature coming soon!")
    }
    
    @objc func searchHistory() {
        let panel = HistorySearchPanel()
        panel.show(relativeTo: window!) { [weak self] command in
            if let command = command, let session = self?.tabManager.getCurrentSession() {
                session.textView.insertText(command, replacementRange: NSRange(location: session.textView.string.count, length: 0))
            }
        }
    }
    
    @objc func showSnippets() {
        let panel = SnippetPanel()
        panel.show(relativeTo: window!) { [weak self] snippet in
            if let snippet = snippet, let session = self?.tabManager.getCurrentSession() {
                session.textView.insertText(snippet.command, replacementRange: NSRange(location: session.textView.string.count, length: 0))
            }
        }
    }
    
    @objc func showAIGenerator() {
        guard AIManager.shared.isAvailable() else {
            showAlert("Please configure AI provider in Settings first")
            return
        }
        
        let panel = AIGeneratorPanel()
        panel.show(relativeTo: window!) { [weak self] command in
            if let command = command, let session = self?.tabManager.getCurrentSession() {
                session.textView.insertText(command, replacementRange: NSRange(location: session.textView.string.count, length: 0))
            }
        }
    }
    
    @objc func showCommandPalette() {
        showAlert("Command palette coming soon!")
    }
    
    @objc func openSettings() {
        let settingsWindow = SettingsWindowController()
        settingsWindow.showWindow(nil)
    }
    
    @objc func increaseFontSize() {
        TerminalSettings.shared.fontSize += 1
        tabManager.tabs.forEach { $0.applyTheme() }
    }
    
    @objc func decreaseFontSize() {
        TerminalSettings.shared.fontSize = max(8, TerminalSettings.shared.fontSize - 1)
        tabManager.tabs.forEach { $0.applyTheme() }
    }
    
    private func showAlert(_ message: String) {
        let alert = NSAlert()
        alert.messageText = message
        alert.alertStyle = .informational
        alert.addButton(withTitle: "OK")
        alert.runModal()
    }
}