-- ═══════════════════════════════════════════════════════════════════
--  MINI CALL OF DUTY - FPS Game Setup (Part 3: Enemy AI + Server Handler)
-- ═══════════════════════════════════════════════════════════════════

local SSS = game:GetService("ServerScriptService")
local RS = game:GetService("ReplicatedStorage")

-- ═══════════════════════════════════════════════════════════════
--  SERVER GAME HANDLER
-- ═══════════════════════════════════════════════════════════════
local serverScript = Instance.new("Script")
serverScript.Name = "GameServer"
serverScript.Parent = SSS
serverScript.Source = [[
local Players = game:GetService("Players")
local RS = game:GetService("ReplicatedStorage")
local Events = RS:WaitForChild("Events")
local Shared = RS:WaitForChild("Shared")
local WeaponData = require(Shared:WaitForChild("WeaponData"))

local scores = {}
local killFeed = {}

-- Player setup
Players.PlayerAdded:Connect(function(player)
	scores[player.UserId] = {kills = 0, deaths = 0, streak = 0}

	player.CharacterAdded:Connect(function(char)
		task.wait(0.5)
		local hum = char:WaitForChild("Humanoid")
		hum.MaxHealth = 100
		hum.Health = 100
		hum.WalkSpeed = 20

		-- Give starter weapon visual
		local tool = Instance.new("Tool")
		tool.Name = "M4A1"
		tool.RequiresHandle = true
		tool.CanBeDropped = false

		local handle = Instance.new("Part")
		handle.Name = "Handle"
		handle.Size = Vector3.new(0.5, 0.5, 3)
		handle.Color = Color3.fromRGB(40, 40, 40)
		handle.Material = Enum.Material.SmoothPlastic
		handle.CanCollide = false
		handle.Anchored = false
		handle.Parent = tool
		tool.Parent = player.Backpack

		-- Gun body
		local barrel = Instance.new("Part")
		barrel.Name = "Barrel"
		barrel.Size = Vector3.new(0.2, 0.2, 2)
		barrel.Color = Color3.fromRGB(30, 30, 30)
		barrel.Material = Enum.Material.Metal
		barrel.CanCollide = false
		barrel.Anchored = false
		local weld = Instance.new("WeldConstraint")
		weld.Part0 = handle
		weld.Part1 = barrel
		weld.Parent = barrel
		barrel.CFrame = handle.CFrame * CFrame.new(0, 0.1, -2)
		barrel.Parent = tool

		-- Magazine
		local mag = Instance.new("Part")
		mag.Name = "Magazine"
		mag.Size = Vector3.new(0.3, 0.8, 0.4)
		mag.Color = Color3.fromRGB(35, 35, 35)
		mag.Material = Enum.Material.SmoothPlastic
		mag.CanCollide = false
		mag.Anchored = false
		local weld2 = Instance.new("WeldConstraint")
		weld2.Part0 = handle
		weld2.Part1 = mag
		weld2.Parent = mag
		mag.CFrame = handle.CFrame * CFrame.new(0, -0.5, -0.5)
		mag.Parent = tool

		-- Health regeneration
		task.spawn(function()
			while hum and hum.Health > 0 do
				task.wait(3)
				if hum.Health < hum.MaxHealth and hum.Health > 0 then
					hum.Health = math.min(hum.MaxHealth, hum.Health + 5)
				end
			end
		end)

		-- Death handler
		hum.Died:Connect(function()
			scores[player.UserId].deaths = scores[player.UserId].deaths + 1
			scores[player.UserId].streak = 0

			-- Respawn after 5 seconds
			task.delay(5, function()
				if player then
					player:LoadCharacter()
				end
			end)
		end)
	end)
end)

-- Handle hit events from clients
Events:WaitForChild("ShootEvent").OnServerEvent:Connect(function(player, data)
	-- Validate the shot
	if not data or not data.hit then return end

	local hitObj = data.hit
	local weaponName = data.weapon or "M4A1"
	local weapon = WeaponData[weaponName]
	if not weapon then return end

	-- Check range
	local char = player.Character
	if not char then return end
	local dist = (data.hitPos - char.Head.Position).Magnitude
	if dist > weapon.range then return end

	-- Find the humanoid of what was hit
	local targetHum = nil
	local isHeadshot = false

	if hitObj:IsA("Model") then
		targetHum = hitObj:FindFirstChildOfClass("Humanoid")
	elseif hitObj.Parent and hitObj.Parent:IsA("Model") then
		targetHum = hitObj.Parent:FindFirstChildOfClass("Humanoid")
	elseif hitObj.Parent and hitObj.Parent.Parent and hitObj.Parent.Parent:IsA("Model") then
		targetHum = hitObj.Parent.Parent:FindFirstChildOfClass("Humanoid")
	end

	-- Check headshot
	if hitObj.Name == "Head" and targetHum then
		isHeadshot = true
	end

	-- Apply damage
	if targetHum then
		local dmg = weapon.damage
		if isHeadshot then dmg = dmg * weapon.headshotMult end

		targetHum:TakeDamage(dmg)

		-- Check if killed
		if targetHum.Health <= 0 then
			local victim = nil
			for _, p in ipairs(Players:GetPlayers()) do
				if p.Character and p.Character:FindFirstChildOfClass("Humanoid") == targetHum then
					victim = p
					break
				end
			end

			if victim then
				scores[player.UserId].kills = scores[player.UserId].kills + 1
				scores[player.UserId].streak = scores[player.UserId].streak + 1
			end

			-- Fire kill event
			Events:WaitForChild("KillEvent"):FireAllClients({
				killer = player.Name,
				victim = victim and victim.Name or "Enemy",
				weapon = weaponName,
				headshot = isHeadshot,
				streak = scores[player.UserId].streak,
			})
		end

		-- Fire damage indicator
		Events:WaitForChild("DamageEvent"):FireClient(player, {
			hit = true,
			headshot = isHeadshot,
			damage = dmg,
		})
	end
end)

-- Game data request
Events:WaitForChild("GetGameData").OnServerInvoke = function(player)
	return {
		scores = scores,
		killFeed = killFeed,
	}
end

-- Kill feed relay
Events:WaitForChild("KillEvent").OnServerEvent:Connect(function(player, data)
	table.insert(killFeed, 1, data)
	if #killFeed > 5 then table.remove(killFeed) end
end)

-- ═══════════════════════════════════════════════════════════════
--  ENEMY AI SYSTEM
-- ═══════════════════════════════════════════════════════════════
local enemySpawns = {
	Vector3.new(60, 2, 80), Vector3.new(-60, 2, 80),
	Vector3.new(70, 2, -80), Vector3.new(-70, 2, -80),
	Vector3.new(0, 2, 100), Vector3.new(0, 2, -80),
	Vector3.new(50, 2, 0), Vector3.new(-50, 2, 0),
	Vector3.new(-40, 2, 50), Vector3.new(40, 2, -50),
	Vector3.new(-80, 2, 30), Vector3.new(80, 2, -30),
}

local enemies = {}
local MAX_ENEMIES = 10
local SPAWN_INTERVAL = 8

local function createEnemy(pos)
	local model = Instance.new("Model")
	model.Name = "Enemy_" .. tostring(#enemies + 1)

	-- Humanoid
	local hum = Instance.new("Humanoid")
	hum.MaxHealth = 80
	hum.Health = 80
	hum.WalkSpeed = 14
	hum.Parent = model

	-- Head
	local head = Instance.new("Part")
	head.Name = "Head"
	head.Size = Vector3.new(1.5, 1.5, 1.5)
	head.Color = Color3.fromRGB(180, 140, 110)
	head.Material = Enum.Material.SmoothPlastic
	head.CanCollide = true
	head.Parent = model
	local headMesh = Instance.new("SpecialMesh")
	headMesh.MeshType = Enum.MeshType.Head
	headMesh.Scale = Vector3.new(1.25, 1.25, 1.25)
	headMesh.Parent = head

	-- Torso
	local torso = Instance.new("Part")
	torso.Name = "HumanoidRootPart"
	torso.Size = Vector3.new(2, 2, 1)
	torso.Color = Color3.fromRGB(60, 80, 40) -- Military green
	torso.Material = Enum.Material.SmoothPlastic
	torso.CanCollide = true
	torso.Parent = model

	-- Legs
	local lleg = Instance.new("Part")
	lleg.Name = "Left Leg"
	lleg.Size = Vector3.new(1, 2, 1)
	lleg.Color = Color3.fromRGB(50, 55, 45)
	lleg.Material = Enum.Material.SmoothPlastic
	lleg.Parent = model

	local rleg = Instance.new("Part")
	rleg.Name = "Right Leg"
	rleg.Size = Vector3.new(1, 2, 1)
	rleg.Color = Color3.fromRGB(50, 55, 45)
	rleg.Material = Enum.Material.SmoothPlastic
	rleg.Parent = model

	-- Arms
	local larm = Instance.new("Part")
	larm.Name = "Left Arm"
	larm.Size = Vector3.new(1, 2, 1)
	larm.Color = Color3.fromRGB(60, 80, 40)
	larm.Material = Enum.Material.SmoothPlastic
	larm.Parent = model

	local rarm = Instance.new("Part")
	rarm.Name = "Right Arm"
	rarm.Size = Vector3.new(1, 2, 1)
	rarm.Color = Color3.fromRGB(60, 80, 40)
	rarm.Material = Enum.Material.SmoothPlastic
	rarm.Parent = model

	-- Motor6D connections
	local function weld(part0, part1, c0, c1)
		local m = Instance.new("Motor6D")
		m.Part0 = part0
		m.Part1 = part1
		if c0 then m.C0 = c0 end
		if c1 then m.C1 = c1 end
		m.Parent = part0
	end

	weld(torso, head, CFrame.new(0, 1.5, 0), CFrame.new(0, 0, 0))
	weld(torso, larm, CFrame.new(-1.5, 0, 0), CFrame.new(0.5, 0, 0))
	weld(torso, rarm, CFrame.new(1.5, 0, 0), CFrame.new(-0.5, 0, 0))
	weld(torso, lleg, CFrame.new(-0.5, -2, 0), CFrame.new(0, 1, 0))
	weld(torso, rleg, CFrame.new(0.5, -2, 0), CFrame.new(0, 1, 0))

	-- Beret/hat
	local hat = Instance.new("Part")
	hat.Name = "Hat"
	hat.Size = Vector3.new(1.8, 0.5, 1.8)
	hat.Color = Color3.fromRGB(40, 50, 30)
	hat.Material = Enum.Material.SmoothPlastic
	hat.CanCollide = false
	hat.Parent = model
	local hatWeld = Instance.new("WeldConstraint")
	hatWeld.Part0 = head
	hatWeld.Part1 = hat
	hatWeld.Parent = hat
	hat.CFrame = head.CFrame * CFrame.new(0, 0.9, 0)

	-- Health bar above head
	local billboard = Instance.new("BillboardGui")
	billboard.Name = "HealthBar"
	billboard.Size = UDim2.new(3, 0, 0.4, 0)
	billboard.StudsOffset = Vector3.new(0, 3.5, 0)
	billboard.AlwaysOnTop = true
	billboard.Parent = head

	local bg = Instance.new("Frame")
	bg.Size = UDim2.new(1, 0, 1, 0)
	bg.BackgroundColor3 = Color3.fromRGB(40, 40, 40)
	bg.BorderSizePixel = 0
	bg.Parent = billboard

	local fill = Instance.new("Frame")
	fill.Name = "Fill"
	fill.Size = UDim2.new(1, 0, 1, 0)
	fill.BackgroundColor3 = Color3.fromRGB(200, 30, 30)
	fill.BorderSizePixel = 0
	fill.Parent = bg

	-- AI Script
	local aiScript = Instance.new("Script")
	aiScript.Source = [[
local humanoid = script.Parent:FindFirstChildOfClass("Humanoid")
local rootPart = script.Parent:FindFirstChild("HumanoidRootPart")
local head = script.Parent:FindFirstChild("Head")
local healthFill = script.Parent:FindFirstChild("Head"):FindFirstChild("HealthBar"):FindFirstChild("Frame"):FindFirstChild("Fill")

if not humanoid or not rootPart then return end

local state = "patrol"
local target = nil
local lastShot = 0
local fireRate = 1.2
local damage = 12
local detectionRange = 80
local attackRange = 60
local patrolPoints = {}
local currentPatrolIndex = 1

-- Generate patrol points
for i = 1, 6 do
	local angle = math.rad(math.random(360))
	local dist = math.random(15, 60)
	table.insert(patrolPoints, rootPart.Position + Vector3.new(math.cos(angle)*dist, 0, math.sin(angle)*dist))
end

-- Find closest player
local function findTarget()
	local closest = nil
	local closestDist = detectionRange
	for _, player in ipairs(game:GetService("Players"):GetPlayers()) do
		if player.Character then
			local hum = player.Character:FindFirstChildOfClass("Humanoid")
			if hum and hum.Health > 0 then
				local dist = (player.Character.Head.Position - rootPart.Position).Magnitude
				if dist < closestDist then
					closest = player
					closestDist = dist
				end
			end
		end
	end
	return closest, closestDist
end

-- Update health bar
humanoid.HealthChanged:Connect(function(health)
	local pct = health / humanoid.MaxHealth
	healthFill.Size = UDim2.new(pct, 0, 1, 0)
	if pct < 0.3 then
		healthFill.BackgroundColor3 = Color3.fromRGB(200, 30, 30)
	else
		healthFill.BackgroundColor3 = Color3.fromRGB(200, 60, 30)
	end
end)

-- Main AI loop
while humanoid and humanoid.Health > 0 do
	task.wait(0.3)

	target, _ = findTarget()

	if target and target.Character then
		local targetHum = target.Character:FindFirstChildOfClass("Humanoid")
		local targetHead = target.Character:FindFirstChild("Head")

		if targetHum and targetHum.Health > 0 and targetHead then
			local dist = (targetHead.Position - rootPart.Position).Magnitude

			-- Face target
			rootPart.CFrame = CFrame.new(rootPart.Position, Vector3.new(targetHead.Position.X, rootPart.Position.Y, targetHead.Position.Z))

			if dist <= attackRange then
				state = "attack"
				-- Shoot at player
				if tick() - lastShot > fireRate then
					lastShot = tick()

					-- Raycast to player
					local direction = (targetHead.Position - head.Position).Unit
					local spread = Vector3.new(math.random()-0.5, math.random()-0.5, math.random()-0.5) * 2
					local hitResult = workspace:Raycast(head.Position, (direction + spread) * attackRange)

					if hitResult then
						-- Muzzle flash
						local flash = Instance.new("Part")
						flash.Size = Vector3.new(0.3, 0.3, 0.3)
						flash.Shape = Enum.PartType.Ball
						flash.Color = Color3.fromRGB(255, 200, 50)
						flash.Material = Enum.Material.Neon
						flash.Anchored = true
						flash.CanCollide = false
						flash.Position = head.Position + direction * 2
						flash.Parent = workspace
						game:GetService("Debris"):AddItem(flash, 0.08)

						-- Bullet trail
						local trail = Instance.new("Part")
						trail.Size = Vector3.new(0.1, 0.1, (head.Position - hitResult.Position).Magnitude)
						trail.CFrame = CFrame.new(head.Position, hitResult.Position) * CFrame.new(0, 0, -trail.Size.Z/2)
						trail.Anchored = true
						trail.CanCollide = false
						trail.Color = Color3.fromRGB(255, 200, 100)
						trail.Material = Enum.Material.Neon
						trail.Transparency = 0.3
						trail.Parent = workspace
						game:GetService("Debris"):AddItem(trail, 0.1)

						-- Check if hit player
						local hitChar = hitResult.Instance
						if hitChar then
							local hitHum = nil
							if hitChar.Parent and hitChar.Parent:FindFirstChildOfClass("Humanoid") then
								hitHum = hitChar.Parent:FindFirstChildOfClass("Humanoid")
							elseif hitChar.Parent and hitChar.Parent.Parent and hitChar.Parent.Parent:FindFirstChildOfClass("Humanoid") then
								hitHum = hitChar.Parent.Parent:FindFirstChildOfClass("Humanoid")
							end

							if hitHum and hitHum ~= humanoid then
								hitHum:TakeDamage(damage)
							end
						end

						-- Impact effect
						local impact = Instance.new("Part")
						impact.Size = Vector3.new(0.5, 0.5, 0.5)
						impact.Shape = Enum.PartType.Ball
						impact.Color = Color3.fromRGB(255, 150, 50)
						impact.Material = Enum.Material.Neon
						impact.Anchored = true
						impact.CanCollide = false
						impact.Position = hitResult.Position
						impact.Parent = workspace
						game:GetService("Debris"):AddItem(impact, 0.15)
					end
				end
			else
				-- Move toward target
				state = "chase"
				humanoid:MoveTo(targetHead.Position)
			end
		end
	else
		-- Patrol
		state = "patrol"
		if #patrolPoints > 0 then
			humanoid:MoveTo(patrolPoints[currentPatrolIndex])
			humanoid.MoveToFinished:Connect(function(reached)
				if reached then
					currentPatrolIndex = (currentPatrolIndex % #patrolPoints) + 1
				end
			end)
		end
	end
end

-- Death effect
local root = script.Parent:FindFirstChild("HumanoidRootPart")
if root then
	for _, v in ipairs(script.Parent:GetDescendants()) do
		if v:IsA("BasePart") then
			v.Anchored = false
			v.BrickColor = BrickColor.new("Dark stone grey")
			local bf = Instance.new("BodyForce")
			bf.Force = Vector3.new(math.random(-50,50), 100, math.random(-50,50))
			bf.Parent = v
			game:GetService("Debris"):AddItem(v, 3)
		end
	end
end

task.delay(3, function()
	if script.Parent then script.Parent:Destroy() end
end)
]]
	aiScript.Parent = model

	-- Position
	local primary = torso
	model.PrimaryPart = primary
	primary.Position = pos
	head.Position = pos + Vector3.new(0, 2.5, 0)
	lleg.Position = pos + Vector3.new(-0.5, -1, 0)
	rleg.Position = pos + Vector3.new(0.5, -1, 0)
	larm.Position = pos + Vector3.new(-1.5, 0, 0)
	rarm.Position = pos + Vector3.new(1.5, 0, 0)

	model.Parent = workspace
	table.insert(enemies, model)
	return model
end

-- Enemy spawner loop
task.spawn(function()
	task.wait(5) -- Initial delay
	while true do
		-- Remove dead enemies
		for i = #enemies, 1, -1 do
			if not enemies[i] or not enemies[i]:FindFirstChildOfClass("Humanoid")
				or enemies[i]:FindFirstChildOfClass("Humanoid").Health <= 0 then
				table.remove(enemies, i)
			end
		end

		-- Spawn new enemies
		if #enemies < MAX_ENEMIES then
			local pos = enemySpawns[math.random(#enemySpawns)]
			createEnemy(pos + Vector3.new(math.random(-5,5), 0, math.random(-5,5)))
		end

		task.wait(SPAWN_INTERVAL)
	end
end)

print("[GameServer] Enemy AI system active. Spawning " .. MAX_ENEMIES .. " enemies.")
]]

print("[CoD FPS] Part 3/5 complete: Server handler + Enemy AI created.")