-- Services
local HttpService = game:GetService("HttpService")
local TweenService = game:GetService("TweenService")
local UserInputService = game:GetService("UserInputService")
local RunService = game:GetService("RunService")
local CoreGui = game:GetService("CoreGui")
local Players = game:GetService("Players")

-- Singleton Check
if getgenv().GeminiChatLoaded then
    if getgenv().GeminiChatUnload then
        getgenv().GeminiChatUnload()
    end
end
getgenv().GeminiChatLoaded = true

-- Generation State
local IsGenerating = false
local StopGeneration = false

-- Configuration
local Config = {
    ApiKey = "",
    Model = "gemini-3-flash-preview", -- Reverted
    History = {}
}

print("[Gemini AI] Loading UI...")

-- Theme & Design System (ChatGPT-like)
local Theme = {
    Background = Color3.fromRGB(52, 53, 65),       -- Main Chat Background
    Sidebar = Color3.fromRGB(32, 33, 35),          -- Sidebar/Header
    InputBG = Color3.fromRGB(64, 65, 79),          -- Input Field
    UserBubble = Color3.fromRGB(32, 33, 35),       -- User Bubble (Darker)
    AIBubble = Color3.fromRGB(68, 70, 84),         -- AI Bubble (Contrast)
    TextPrimary = Color3.fromRGB(236, 236, 241),   -- Main Text
    TextSecondary = Color3.fromRGB(142, 142, 160), -- Subtitles/Placeholders
    Accent = Color3.fromRGB(16, 163, 127),         -- ChatGPT Green
    CodeBlock = Color3.black,                      -- Code Block BG
    Scrollbar = Color3.fromRGB(86, 88, 105),
    Radius = UDim.new(0, 6)
}

local function MarkdownToRichText(text)
    -- Escaping
    text = text:gsub("&", "&amp;"):gsub("<", "&lt;"):gsub(">", "&gt;"):gsub("\"", "&quot;"):gsub("'", "&apos;")
    
    -- Bold **text** or __text__
    text = text:gsub("%*%*(.-)%*%*", "<b>%1</b>")
    text = text:gsub("__(.-)__", "<b>%1</b>")
    
    -- Italic *text* or _text_
    text = text:gsub("%*(.-)%*", "<i>%1</i>")
    text = text:gsub("_(.-)_", "<i>%1</i>")
    
    -- Headers ### Text (Line aware)
    text = text:gsub("(\n?)###%s*(.-)(\n?)", "%1<font size=\"18\"><b>%2</b></font>%3")
    text = text:gsub("(\n?)##%s*(.-)(\n?)", "%1<font size=\"20\"><b>%2</b></font>%3")
    text = text:gsub("(\n?)#%s*(.-)(\n?)", "%1<font size=\"22\"><b>%2</b></font>%3")
    
    -- Bullet points
    text = text:gsub("\n%* ", "\n  • ")
    text = text:gsub("^%* ", "  • ")
    
    return text
end

local function Typewrite(label, text, speed)
    label.Text = ""
    local displayed = ""
    
    -- UTF-8 safe iteration
    for _, code in utf8.codes(text) do
        if StopGeneration then break end
        displayed = displayed .. utf8.char(code)
        label.Text = displayed
        
        -- Auto-scroll
        if ChatScroll then
            ChatScroll.CanvasPosition = Vector2.new(0, ChatScroll.AbsoluteCanvasSize.Y)
        end
        
        -- Speed control (approximate)
        if speed and speed > 0 then
            task.wait(speed)
        else
            task.wait(0.005)
        end
    end
    
    label.Text = text -- Ensure it's fully set
end

-- Utility Functions
local function Create(className, properties, children)
    local instance = Instance.new(className)
    for k, v in pairs(properties or {}) do
        instance[k] = v
    end
    if children then
        for _, child in ipairs(children) do
            child.Parent = instance
        end
    end
    return instance
end

local function Tween(instance, info, goals)
    local tween = TweenService:Create(instance, info, goals)
    tween:Play()
    return tween
end

local function GetTextSize(text, font, fontSize, maxWidth)
    return game:GetService("TextService"):GetTextSize(text, fontSize, font, Vector2.new(maxWidth, 10000))
end

-- UI Construction
local ScreenGui = Create("ScreenGui", {
    Name = "GeminiChatUI",
    Parent = (RunService:IsStudio() and Players.LocalPlayer:WaitForChild("PlayerGui")) or CoreGui,
    ResetOnSpawn = false,
    ZIndexBehavior = Enum.ZIndexBehavior.Sibling
})

local MainFrame = Create("Frame", {
    Name = "MainFrame",
    Parent = ScreenGui,
    BackgroundColor3 = Theme.Background,
    Size = UDim2.fromOffset(500, 700),
    Position = UDim2.new(0.5, 0, 0.5, -350), -- Centered top
    AnchorPoint = Vector2.new(0.5, 0), -- Anchor to TOP
    BorderSizePixel = 0,
    ClipsDescendants = true
}, {
    Create("UICorner", { CornerRadius = Theme.Radius }),
    Create("UIStroke", { Color = Color3.fromRGB(80, 80, 80), Thickness = 1, Transparency = 0.5 })
})

-- Dragging Logic
local Dragging, DragInput, DragStart, StartPos
-- Forward Declare for Minimize
local ChatScroll, InputContainer

MainFrame.InputBegan:Connect(function(input)
    if input.UserInputType == Enum.UserInputType.MouseButton1 then
        Dragging = true
        DragStart = input.Position
        StartPos = MainFrame.Position
        
        input.Changed:Connect(function()
            if input.UserInputState == Enum.UserInputState.End then
                Dragging = false
            end
        end)
    end
end)

MainFrame.InputChanged:Connect(function(input)
    if input.UserInputType == Enum.UserInputType.MouseMovement then
        DragInput = input
    end
end)

UserInputService.InputChanged:Connect(function(input)
    if input == DragInput and Dragging then
        local delta = input.Position - DragStart
        Tween(MainFrame, TweenInfo.new(0.1), {
            Position = UDim2.new(StartPos.X.Scale, StartPos.X.Offset + delta.X, StartPos.Y.Scale, StartPos.Y.Offset + delta.Y)
        })
    end
end)

-- Header
local Header = Create("Frame", {
    Name = "Header",
    Parent = MainFrame,
    Size = UDim2.new(1, 0, 0, 50),
    BackgroundColor3 = Theme.Sidebar,
    BorderSizePixel = 0
}, {
    Create("TextLabel", {
        Text = "Gemini AI",
        TextColor3 = Theme.TextPrimary,
        Font = Enum.Font.GothamBold,
        TextSize = 18,
        Size = UDim2.fromScale(1, 1),
        BackgroundTransparency = 1,
        Position = UDim2.fromOffset(15, 0),
        TextXAlignment = Enum.TextXAlignment.Left
    }),
    Create("UICorner", { CornerRadius = UDim.new(0, 6) }), -- Rounded top (visual fix handled by Frame clipping)
    Create("Frame", { -- Bottom border fix for rounded header
        Size = UDim2.new(1, 0, 0, 5),
        Position = UDim2.new(0, 0, 1, -5),
        BackgroundColor3 = Theme.Sidebar,
        BorderSizePixel = 0
    }) 
})

-- Close Button
local CloseBtn = Create("TextButton", {
    Parent = Header,
    Text = "×",
    TextColor3 = Theme.TextSecondary,
    Font = Enum.Font.Gotham,
    TextSize = 24,
    BackgroundTransparency = 1,
    Size = UDim2.fromOffset(40, 40),
    Position = UDim2.new(1, -45, 0.5, -20),
    AutoButtonColor = false
})

CloseBtn.MouseEnter:Connect(function() Tween(CloseBtn, TweenInfo.new(0.2), {TextColor3 = Color3.new(1, 0.3, 0.3)}) end)
CloseBtn.MouseLeave:Connect(function() Tween(CloseBtn, TweenInfo.new(0.2), {TextColor3 = Theme.TextSecondary}) end)
CloseBtn.MouseButton1Click:Connect(function() 
    getgenv().GeminiChatUnload() 
end)

-- Minimize Button
local Minimized = false
local MinimizeBtn = Create("TextButton", {
    Parent = Header,
    Text = "-",
    TextColor3 = Theme.TextSecondary,
    Font = Enum.Font.Gotham,
    TextSize = 24,
    BackgroundTransparency = 1,
    Size = UDim2.fromOffset(40, 40),
    Position = UDim2.new(1, -85, 0.5, -20),
    AutoButtonColor = false
})

MinimizeBtn.MouseEnter:Connect(function() Tween(MinimizeBtn, TweenInfo.new(0.2), {TextColor3 = Theme.Accent}) end)
MinimizeBtn.MouseLeave:Connect(function() Tween(MinimizeBtn, TweenInfo.new(0.2), {TextColor3 = Theme.TextSecondary}) end)

MinimizeBtn.MouseButton1Click:Connect(function()
    Minimized = not Minimized
    local targetSize = Minimized and UDim2.fromOffset(500, 50) or UDim2.fromOffset(500, 700)
    Tween(MainFrame, TweenInfo.new(0.3, Enum.EasingStyle.Quart, Enum.EasingDirection.Out), {Size = targetSize})
    
    -- Delay visibility for smooth clipping effect or just toggle
    if not Minimized then
        ChatScroll.Visible = true
        InputContainer.Visible = true
        MinimizeBtn.Text = "-"
    else
        MinimizeBtn.Text = "+"
        task.delay(0.2, function()
            if Minimized then
                ChatScroll.Visible = false
                InputContainer.Visible = false
            end
        end)
    end
end)

-- Visibility Toggle (Left Control)
local Hidden = false
UserInputService.InputBegan:Connect(function(input, gpe)
    if gpe then return end
    if input.KeyCode == Enum.KeyCode.LeftControl then
        Hidden = not Hidden
        ScreenGui.Enabled = not Hidden
    end
end)

-- Scroll Container for content
ChatScroll = Create("ScrollingFrame", {
    Parent = MainFrame,
    Size = UDim2.new(1, 0, 1, -135), -- Adjusted for 50px header + 80px input + padding
    Position = UDim2.new(0, 0, 0, 50),
    BackgroundTransparency = 1,
    ScrollBarThickness = 6,
    ScrollBarImageColor3 = Theme.Scrollbar,
    CanvasSize = UDim2.new(0, 0, 0, 0),
    AutomaticCanvasSize = Enum.AutomaticSize.Y
}, {
    Create("UIListLayout", {
        SortOrder = Enum.SortOrder.LayoutOrder,
        Padding = UDim.new(0, 15),
        HorizontalAlignment = Enum.HorizontalAlignment.Center
    }),
    Create("UIPadding", {
        PaddingTop = UDim.new(0, 10),
        PaddingBottom = UDim.new(0, 15), -- Slightly more padding at bottom
        PaddingLeft = UDim.new(0, 10),
        PaddingRight = UDim.new(0, 10)
    })
})

-- Input Area Redesign
InputContainer = Create("Frame", {
    Parent = MainFrame,
    Size = UDim2.new(1, 0, 0, 80),
    Position = UDim2.new(0, 0, 1, -80),
    BackgroundTransparency = 1,
    BorderSizePixel = 0
})

local Pill = Create("Frame", {
    Parent = InputContainer,
    Size = UDim2.new(1, -30, 0, 50),
    Position = UDim2.new(0.5, 0, 0.5, 0),
    AnchorPoint = Vector2.new(0.5, 0.5),
    BackgroundColor3 = Theme.InputBG,
    BackgroundTransparency = 0.2,
    BorderSizePixel = 0
}, {
    Create("UICorner", { CornerRadius = UDim.new(1, 0) }), -- Oval shape
    Create("UIStroke", { Color = Color3.fromRGB(255, 255, 255), Transparency = 0.9, Thickness = 1 })
})

local InputBox = Create("TextBox", {
    Parent = Pill,
    Size = UDim2.new(1, -60, 1, 0),
    Position = UDim2.new(0, 20, 0, 0),
    BackgroundTransparency = 1,
    TextColor3 = Theme.TextPrimary,
    PlaceholderText = "Ask anything...", -- Updated as per image style
    PlaceholderColor3 = Theme.TextSecondary,
    Font = Enum.Font.Gotham,
    TextSize = 14,
    TextWrapped = true,
    ClearTextOnFocus = false,
    TextXAlignment = Enum.TextXAlignment.Left,
    TextYAlignment = Enum.TextYAlignment.Center,
    Text = ""
})

local SendBtn = Create("ImageButton", {
    Parent = Pill,
    Size = UDim2.fromOffset(32, 32),
    Position = UDim2.new(1, -9, 0.5, 0),
    AnchorPoint = Vector2.new(1, 0.5),
    BackgroundTransparency = 1, -- Removed white background
    Image = "rbxassetid://123749085081505", -- Your provided Send ID
    ImageColor3 = Color3.fromRGB(255, 255, 255),
    ScaleType = Enum.ScaleType.Fit,
    AutoButtonColor = true
})

local function SetGenerating(state)
    IsGenerating = state
    if state then
        SendBtn.Image = "rbxassetid://109356409844353" -- Your provided Stop ID
        StopGeneration = false
    else
        SendBtn.Image = "rbxassetid://123749085081505" -- Your provided Send ID
    end
end

-- Helper to make text selectable/copyable if possible (TextBox read-only trick) or just Label
-- Roblox TextLabels are not copyable.
-- We will implement a special rendering for code blocks.

local function ProcessText(text)
    local parts = {}
    local pattern = "```(.-)```"
    local lastPos = 1
    
    -- Use find instead of gmatch to get positions correctly
    local startPos, endPos, code = text:find(pattern, lastPos)
    
    while startPos do
        -- Add preceding text
        local preText = text:sub(lastPos, startPos - 1)
        if #preText > 0 then
            table.insert(parts, {Type = "Text", Content = preText})
        end
        
        -- Add code block (strip language identifier and trim)
        local cleanCode = code:gsub("^%w+\n", ""):gsub("^%s+", ""):gsub("%s+$", "")
        table.insert(parts, {Type = "Code", Content = cleanCode})
        
        lastPos = endPos + 1
        startPos, endPos, code = text:find(pattern, lastPos)
    end
    
    -- Add remaining text
    local remain = text:sub(lastPos)
    if #remain > 0 then
        table.insert(parts, {Type = "Text", Content = remain})
    end
    
    if #parts == 0 then table.insert(parts, {Type = "Text", Content = text}) end
    
    for _, part in ipairs(parts) do
        if part.Type == "Text" then
            part.Content = MarkdownToRichText(part.Content)
        end
    end
    
    return parts
end

local function RenderMessage(role, text)
    local isUser = (role == "User")
    local bubbleColor = isUser and Theme.UserBubble or Theme.AIBubble
    
    -- Container for the whole message row
    local Row = Create("Frame", {
        Parent = ChatScroll,
        Size = UDim2.new(1, 0, 0, 0), -- Automatic size
        BackgroundTransparency = 1,
        AutomaticSize = Enum.AutomaticSize.Y
    })
    
    -- Icon / Label Container
    if isUser then
        Create("TextLabel", {
            Parent = Row,
            Text = "You",
            TextColor3 = Theme.TextSecondary,
            Font = Enum.Font.GothamBold,
            TextSize = 12,
            Size = UDim2.new(1, -15, 0, 20),
            Position = UDim2.new(0, 0, 0, 0),
            BackgroundTransparency = 1,
            TextXAlignment = Enum.TextXAlignment.Right
        })
    else
        Create("ImageLabel", {
            Parent = Row,
            Size = UDim2.fromOffset(30, 30),
            BackgroundTransparency = 1,
            Position = UDim2.new(0, 0, 0, 0),
            Image = "rbxassetid://119604644446321", -- User provided AI icon
        }, { Create("UICorner", { CornerRadius = UDim.new(0, 4) }) })
    end
    
    -- Content Container (The Bubble)
    local ContentWidth = 380
    local Bubble = Create("Frame", {
        Parent = Row,
        BackgroundColor3 = bubbleColor,
        Size = UDim2.new(0, ContentWidth, 0, 0), -- Auto Y
        Position = isUser and UDim2.new(1, -10, 0, 22) or UDim2.new(0, 40, 0, 0),        
        AnchorPoint = isUser and Vector2.new(1, 0) or Vector2.new(0, 0),
        AutomaticSize = Enum.AutomaticSize.Y,
        BackgroundTransparency = 0
    }, {
        Create("UICorner", { CornerRadius = UDim.new(0, 6) }),
        Create("UIListLayout", {
            SortOrder = Enum.SortOrder.LayoutOrder,
            Padding = UDim.new(0, 8)
        }),
        Create("UIPadding", {
            PaddingTop = UDim.new(0, 10),
            PaddingBottom = UDim.new(0, 10),
            PaddingLeft = UDim.new(0, 12),
            PaddingRight = UDim.new(0, 12)
        })
    })
    
    -- Generation Logic
    task.spawn(function()
        local parts = ProcessText(text)
        
        for _, part in ipairs(parts) do
            if StopGeneration then break end
            
            if part.Type == "Text" then
                local label = Create("TextLabel", {
                    Parent = Bubble,
                    Text = "", 
                    TextColor3 = Theme.TextPrimary,
                    Font = Enum.Font.Gotham,
                    TextSize = 14,
                    TextWrapped = true,
                    BackgroundTransparency = 1,
                    Size = UDim2.new(1, 0, 0, 0),
                    AutomaticSize = Enum.AutomaticSize.Y,
                    TextXAlignment = Enum.TextXAlignment.Left,
                    RichText = true
                })
                
                if isUser then
                    label.Text = part.Content
                else
                    Typewrite(label, part.Content)
                end
            elseif part.Type == "Code" then
                local codeBox
                local rawContent = part.Content -- Store raw content for copying
                
                local codeContainer = Create("Frame", {
                    Parent = Bubble,
                    BackgroundColor3 = Color3.fromRGB(30, 30, 30),
                    BackgroundTransparency = 0.2,
                    Size = UDim2.new(1, 0, 0, 0),
                    AutomaticSize = Enum.AutomaticSize.Y,
                    BorderSizePixel = 0
                }, {
                    Create("UICorner", { CornerRadius = UDim.new(0, 4) }),
                    Create("UIPadding", {
                        PaddingTop = UDim.new(0, 8),
                        PaddingBottom = UDim.new(0, 8),
                        PaddingLeft = UDim.new(0, 8),
                        PaddingRight = UDim.new(0, 8)
                    }),
                    Create("UIListLayout", {
                        SortOrder = Enum.SortOrder.LayoutOrder,
                        Padding = UDim.new(0, 4)
                    })
                })
                
                local codeHeader = Create("Frame", {
                    Parent = codeContainer,
                    Size = UDim2.new(1, 0, 0, 20),
                    BackgroundTransparency = 1
                })
                
                Create("TextLabel", {
                    Parent = codeHeader,
                    Text = "Code",
                    TextColor3 = Theme.TextSecondary,
                    Font = Enum.Font.GothamBold,
                    TextSize = 12,
                    Size = UDim2.new(1, 0, 1, 0),
                    BackgroundTransparency = 1,
                    TextXAlignment = Enum.TextXAlignment.Left
                })
                
                local copyBtn = Create("TextButton", {
                    Parent = codeHeader,
                    Text = "Copy",
                    TextColor3 = Theme.TextSecondary,
                    Font = Enum.Font.Gotham,
                    TextSize = 12,
                    Size = UDim2.new(0, 40, 1, 0),
                    Position = UDim2.new(1, -45, 0, 0),
                    BackgroundTransparency = 1
                })
                
                copyBtn.MouseButton1Click:Connect(function()
                    local clipboardFunc = setclipboard or toclipboard or (Synapse and Synapse.write_clipboard)
                    if clipboardFunc then
                        clipboardFunc(rawContent) -- Use raw content instead of Box.Text to avoid truncation/corruption
                        copyBtn.Text = "Copied!"
                        task.wait(2)
                        copyBtn.Text = "Copy"
                    end
                end)
                
                codeBox = Create("TextBox", {
                    Parent = codeContainer,
                    Text = isUser and rawContent or "", 
                    TextColor3 = Color3.fromRGB(200, 200, 200),
                    Font = Enum.Font.Code,
                    TextSize = 13,
                    TextWrapped = true,
                    BackgroundTransparency = 1,
                    Size = UDim2.new(1, 0, 0, 0),
                    AutomaticSize = Enum.AutomaticSize.Y,
                    TextXAlignment = Enum.TextXAlignment.Left,
                    TextYAlignment = Enum.TextYAlignment.Top,
                    ClearTextOnFocus = false,
                    TextEditable = false,
                    MultiLine = true
                })

                if not isUser then
                    Typewrite(codeBox, rawContent)
                end
            end
        end
        
        if ChatScroll then
            ChatScroll.CanvasPosition = Vector2.new(0, ChatScroll.AbsoluteCanvasSize.Y)
        end
    end)
end
    
    -- Final auto-scroll and animation bypass for sharpness
    task.spawn(function()
        task.wait()
        ChatScroll.CanvasPosition = Vector2.new(0, ChatScroll.AbsoluteCanvasSize.Y)
    end)


-- Since CanvasGroup might crash some executors, we will just tween the Bubble transparency? 
-- Too complex for recursive tween. Let's just pop it in.

local function SendMessage()
    if IsGenerating then
        StopGeneration = true
        SetGenerating(false)
        return
    end

    local text = InputBox.Text
    if text:gsub("%s+", "") == "" then return end
    
    InputBox.Text = ""
    SetGenerating(true)
    RenderMessage("User", text)
    
    table.insert(Config.History, {
        role = "user",
        parts = {{text = text}}
    })
    
    -- Show Loading Indicator
    local loadingMsg = Create("TextLabel", {
        Parent = ChatScroll,
        Text = "Gemini is thinking...",
        TextColor3 = Theme.TextSecondary,
        Font = Enum.Font.Gotham,
        TextSize = 12,
        Size = UDim2.new(1, 0, 0, 20),
        BackgroundTransparency = 1
    })
    
    task.spawn(function()
        local httpRequest = (syn and syn.request) or http_request or request or (Fluxus and Fluxus.request)
        local url = string.format("https://generativelanguage.googleapis.com/v1beta/models/%s:generateContent?key=%s", Config.Model, Config.ApiKey)
        
        local body = { contents = Config.History }
        
        local success, res
        if httpRequest then
            success, res = pcall(function()
                return httpRequest({
                    Url = url,
                    Method = "POST",
                    Headers = { ["Content-Type"] = "application/json" },
                    Body = HttpService:JSONEncode(body)
                })
            end)
        else
            success, res = pcall(function()
                return { 
                    Body = HttpService:PostAsync(url, HttpService:JSONEncode(body), Enum.HttpContentType.ApplicationJson),
                    StatusCode = 200
                }
            end)
        end
        
        loadingMsg:Destroy()
        
        if success and res then
            local data = HttpService:JSONDecode(res.Body or "{}")
            if data and data.candidates and data.candidates[1] then
                local responseText = data.candidates[1].content.parts[1].text
                RenderMessage("Gemini", responseText)
                table.insert(Config.History, {
                    role = "model",
                    parts = {{text = responseText}}
                })
            else
                RenderMessage("Gemini", "Error: " .. (data.error and data.error.message or "Unknown response"))
            end
        else
            RenderMessage("Gemini", "Connection Failed.")
        end
        
        SetGenerating(false)
    end)
end

SendBtn.MouseButton1Click:Connect(SendMessage)
InputBox.FocusLost:Connect(function(enter)
    if enter then SendMessage() end
end)

-- Unload Logic
getgenv().GeminiChatUnload = function()
    pcall(function() ScreenGui:Destroy() end)
    getgenv().GeminiChatLoaded = false
end

-- Welcome Message
RenderMessage("Gemini", "Hello! I am **Gemini AI**. How can I help you today?")
print("[Gemini AI] UI Loaded Successfully!")