// Package tui defines the pure TUI model, messages, update, and view.
// Zero I/O, zero side effects. Only data transformations.
package tui

// Screen identifies the current TUI screen.
type Screen int

const (
	ScreenMain         Screen = iota
	ScreenAgentList           // list all agents with status
	ScreenAgentActions        // actions for a selected agent
	ScreenLogs                // tail log output
	ScreenServer              // server-wide process management
	ScreenTestOutput          // test run output
)

// Model is the complete TUI state — pure data.
type Model struct {
	Screen       Screen
	Agents       []AgentView
	Cursor       int
	Selected     *AgentView // nil when no agent selected
	LogLines     []string
	LogScroll    int
	StatusMsg    string // flash message ("Started OK", "Error: ...")
	WindowWidth  int
	WindowHeight int

	// Unified launcher state
	LauncherRunning bool
	LauncherPID     int
	LauncherUptime  string
	LauncherMemory  string
	LauncherCPU     string
	LauncherLogSize string
}

// AgentView is a pre-formatted projection of an agent for display.
type AgentView struct {
	ID        string
	Name      string
	Version   string
	Desc      string
	Enabled   bool
	Running   bool
	PID       int
	Instances int    // number of running instances (>1 means duplicates)
	Uptime    string // formatted: "2h 15m"
	Memory    string // formatted: "42 MB"
	CPU       string // formatted: "1.2%"
	LogSize   string // formatted: "350 KB"
}

// MenuOption represents a selectable menu item.
type MenuOption struct {
	Label string
	Desc  string
}

// MainMenuOptions returns the options for the main screen.
func MainMenuOptions() []MenuOption {
	return []MenuOption{
		{Label: "Agents", Desc: "Gestionar agentes"},
		{Label: "Server", Desc: "Gestionar launcher unificado"},
		{Label: "Quit", Desc: "Salir"},
	}
}

// ServerMenuOptions returns the available server-wide actions.
func ServerMenuOptions(running bool) []MenuOption {
	if running {
		return []MenuOption{
			{Label: "Stop", Desc: "Detener el launcher"},
			{Label: "Restart", Desc: "Reiniciar el launcher"},
			{Label: "Kill", Desc: "SIGKILL forzado"},
			{Label: "Rebuild & Restart", Desc: "Build + reiniciar"},
			{Label: "Logs", Desc: "Ver log del launcher"},
			{Label: "Run Tests", Desc: "Ejecutar todos los tests"},
		}
	}
	return []MenuOption{
		{Label: "Start", Desc: "Iniciar el launcher unificado"},
		{Label: "Rebuild & Restart", Desc: "Build + iniciar"},
		{Label: "Run Tests", Desc: "Ejecutar todos los tests"},
	}
}

// AgentActionOptions returns the available actions based on agent state.
func AgentActionOptions(enabled bool) []MenuOption {
	if enabled {
		return []MenuOption{
			{Label: "Restart", Desc: "Reiniciar launcher para aplicar cambios"},
			{Label: "Disable", Desc: "Desactivar agente (requiere restart)"},
			{Label: "Logs", Desc: "Ver log del launcher"},
		}
	}
	return []MenuOption{
		{Label: "Restart", Desc: "Reiniciar launcher para aplicar cambios"},
		{Label: "Enable", Desc: "Activar agente (requiere restart)"},
		{Label: "Logs", Desc: "Ver log del launcher"},
	}
}

// InitialModel returns the starting state.
func InitialModel() Model {
	return Model{Screen: ScreenMain}
}