-- Navigation System for Virtual Smartphone
-- Handles screen transitions and state management

-- Screen registry - maps screen names to RML file paths
local screens = {
    home = "demo.rml",
    lock = "screens/lock.rml",
    dialer = "screens/dialer.rml",
    contacts = "screens/contacts.rml",
    messages = "screens/messages.rml",
    settings = "screens/settings.rml",
    browser = "screens/browser.rml"
}

-- Navigation history stack
local history = {}

-- Current screen name
local current_screen = "home"

-- Navigate to a screen by name
function navigateTo(screen_name)
    local path = screens[screen_name]
    if path then
        -- Push current screen to history before navigating
        table.insert(history, current_screen)
        current_screen = screen_name

        -- Load the new screen using C++ function
        local success = loadScreen(path)
        if success then
            print("Navigated to: " .. screen_name)
        else
            -- Restore previous state on failure
            current_screen = table.remove(history)
            print("Failed to navigate to: " .. screen_name)
        end
        return success
    else
        print("Unknown screen: " .. screen_name)
        return false
    end
end

-- Go back to previous screen
function goBack()
    if #history > 0 then
        local previous = table.remove(history)
        local path = screens[previous]
        if path then
            current_screen = previous
            loadScreen(path)
            print("Back to: " .. previous)
            return true
        end
    else
        print("No history to go back to")
    end
    return false
end

-- Go to home screen (clear history)
function goHome()
    history = {}
    current_screen = "home"
    loadScreen(screens.home)
    print("Navigated to home")
end

-- Get current screen name
function getCurrentScreen()
    return current_screen
end

-- Check if we can go back
function canGoBack()
    return #history > 0
end

-- Clear navigation history
function clearHistory()
    history = {}
end

-- Get history depth
function getHistoryDepth()
    return #history
end

print("Navigation system initialized")