funmow/execution_context.go

package funmow

import (
	"fmt"
	"regexp"
	"strings"
	"unicode"
)

const (
	MatchContext      = 1 << iota
	MatchGlobalDBRef  = 1 << iota
	MatchGlobalPlayer = 1 << iota
	MatchInventory    = 1 << iota
	MatchRelative     = 1 << iota
	MatchExitAliases  = 1 << iota
	MatchExitType     = 1 << iota
	MatchRoomType     = 1 << iota
	MatchPlayerType   = 1 << iota
	MatchThingType    = 1 << iota
	MatchAnyType      = MatchExitType | MatchRoomType | MatchPlayerType | MatchThingType
	MatchStuffTypes   = MatchExitType | MatchRoomType | MatchThingType
)

type ExecutionContext struct {
	actor            Object
	context          Object
	inbound          chan PlayerEvent
	outbound         chan PlayerEvent
	eventDistributor *EventDistributor
	db               *DB
	factory          *ObjectFactory
	forceContext     bool
}

func NewForceContext(e *EventDistributor, w *DB, outbound chan PlayerEvent) *ExecutionContext {

	c := new(ExecutionContext)

	c.outbound = outbound
	c.eventDistributor = e
	c.db = w
	c.factory = NewObjectFactory(w)
	c.forceContext = true
	return c
}

func NewExecutionContext(actorID DBRef, e *EventDistributor, w *DB, outbound chan PlayerEvent) *ExecutionContext {

	c := new(ExecutionContext)

	actor, found := w.Fetch(actorID)
	if !found {
		return nil
	}

	c.actor = actor
	c.outbound = outbound
	c.eventDistributor = e
	c.db = w
	c.factory = NewObjectFactory(w)

	return c
}

func (c *ExecutionContext) StartInboundChannel() chan PlayerEvent {
	c.inbound = make(chan PlayerEvent)
	inboundBuffer := make(chan PlayerEvent)

	go func() {

		// An inbound event buffer to protect the event distributor from long
		// running tasks. The alternative is to run each inbound event in a
		// separate goroutine but that has potential problems (ie, two emits
		// arrive in order;  the first one requires an extra DB lookup to sort
		// out context. Now the second one ends up sending its output event
		// before the first, and the client sees things backwards.

		queue := make([]*PlayerEvent, 0)
		running := true
		for running {
			if len(queue) == 0 {
				select {
				case newEvent, ok := <-c.inbound:
					if !ok {
						running = false
						break
					}
					queue = append(queue, &newEvent)
				}
			} else {
				event := queue[0]
				select {
				case newEvent, ok := <-c.inbound:
					if !ok {
						running = false
						break
					}
					queue = append(queue, &newEvent)
				case inboundBuffer <- *event:
					queue = queue[1:]
				}
			}
		}
		// closure of c.inbound is the signal from the event distributor that we need to die.
		// we then close  inboundBuffer to tell the event goroutine to die
		close(inboundBuffer)
	}()

	go func() {
		for {
			event, ok := <-inboundBuffer
			if !ok {
				break
			}
			c.HandleEvent(event)
		}
		// mark player as offline
		if c.actor.Type == "player" {
			c.actor.SetFlag("online", false)
			c.actor.Commit()
		}
		// and finally we tell the event distributor to delete us.
		c.outbound <- PlayerEvent{src: c.actor.ID, dst: c.actor.ID, messageType: EventTypeTeardownComplete}
	}()

	return c.inbound
}

func (c *ExecutionContext) HandleEvent(m PlayerEvent) {

	if m.messageType == EventTypeForce {
		found := false
		c.actor, found = c.db.Fetch(m.dst)
		contextID, found := c.db.GetParent(c.actor.ID)
		if found {
			c.context, _ = c.db.Fetch(contextID)
		} else {
			c.context, _ = c.db.Fetch(0)
		}
		if !found {
			return
		}
		c.evaluateCommand(m)
		return
	}

	c.actor.Refresh()
	contextID, found := c.db.GetParent(c.actor.ID)
	if found {
		c.context, _ = c.db.Fetch(contextID)
	} else {
		c.context, _ = c.db.Fetch(0)
	}

	switch m.messageType {
	case EventTypeLogin:
		if c.actor.Type == "player" {
			c.actor.SetFlag("online", true)
			c.actor.Commit()
			c.system("Yay! %s has connected! Oh boy!", c.actor.ColorName())
			c.oemit(c.context.ID, "You hear a rustling as %s awakens from a slumber.", c.actor.ColorName())
		}
	case EventTypeEmit:
		fallthrough
	case EventTypeOEmit:
		if m.dst == c.context.ID {
			c.output("%s", m.message)
		}
	case EventTypePEmit:
		c.output("%s", m.message)
	case EventTypeWall:
		speaker, found := c.db.Fetch(m.src)
		if !found {
			break
		}
		c.output("In the distance, you hear %s bellow out: \"%s\"", speaker.ColorName(), m.message)
	case EventTypeSystem:
		c.output(m.message)
	case EventTypePage:
		speaker, found := c.db.Fetch(m.src)
		if !found {
			break
		}
		c.output("%s pages: %s", speaker.ColorName(), m.message)
	case EventTypeSay:
		if m.dst == c.context.ID {
			speaker, found := c.db.Fetch(m.src)
			if !found {
				break
			}
			c.output("%s says \"%s\"", speaker.ColorName(), m.message)
		}
	case EventTypePose:
		if m.dst == c.context.ID {
			if m.src == c.actor.ID {
				c.output("%s %s", c.actor.ColorName(), m.message)
			} else {
				speaker, found := c.db.Fetch(m.src)
				if !found {
					break
				}
				c.output("%s %s", speaker.ColorName(), m.message)
			}
		}
	case EventTypeCommand:
		c.evaluateCommand(m)
	}
}

func (c *ExecutionContext) evaluateCommand(m PlayerEvent) {
	command := m.message
	switch {
	case command == "whoami":
		c.output(c.actor.Name)
	case command == "l":
		c.lookCmd("")
	case command == "look":
		c.lookCmd("")
	case strings.HasPrefix(command, "l "): // look at
		c.lookCmd(strings.TrimPrefix(command, "l "))
	case strings.HasPrefix(command, "look "): // look at
		c.lookCmd(strings.TrimPrefix(command, "look "))
	case strings.HasPrefix(command, "ex "):
		c.examineCmd(strings.TrimPrefix(command, "ex "))
	case strings.HasPrefix(command, "examine "):
		c.examineCmd(strings.TrimPrefix(command, "examine "))
	case strings.HasPrefix(command, "\""):
		c.sayCmd(strings.TrimPrefix(command, "\""))
	case strings.HasPrefix(command, "say "):
		c.sayCmd(strings.TrimPrefix(command, "say "))
	case strings.HasPrefix(command, ":"):
		c.poseCmd(strings.TrimPrefix(command, ":"))
	case strings.HasPrefix(command, "pose "):
		c.poseCmd(strings.TrimPrefix(command, "pose "))
	case strings.HasPrefix(command, "p "):
		c.pageCmd(command)
	case strings.HasPrefix(command, "page "):
		c.pageCmd(command)
	case command == "i":
		c.inventoryCmd()
	case command == "inventory":
		c.inventoryCmd()
	case strings.HasPrefix(command, "get "):
		c.getCmd(strings.TrimPrefix(command, "get "))
	case strings.HasPrefix(command, "drop "):
		c.dropCmd(strings.TrimPrefix(command, "drop "))
	case strings.HasPrefix(command, "give "):
		c.giveCmd(command)
	case strings.HasPrefix(command, "put "):
		c.putCmd(command)
	case strings.HasPrefix(command, "enter "):
		c.enterCmd(strings.TrimPrefix(command, "enter "))
	case command == "leave":
		c.leaveCmd()
	case command == "quit":
		c.quitCmd(m.connectionID)
	case command == "WHO":
		c.whoCmd()
	case strings.HasPrefix(command, "@create "):
		c.createCmd(strings.TrimPrefix(command, "@create "))
	case strings.HasPrefix(command, "@dig "):
		c.digCmd(command)
	case strings.HasPrefix(command, "@open "):
		c.openCmd(command)
	case strings.HasPrefix(command, "@name "):
		c.nameCmd(command)
	case strings.HasPrefix(command, "@desc "):
		c.descCmd(command)
	case strings.HasPrefix(command, "@password "):
		c.passwordCmd(command)
	case strings.HasPrefix(command, "@set "):
		c.setCmd(command)
	case strings.HasPrefix(command, "@color "):
		c.colorCmd(command)
	case strings.HasPrefix(command, "@tel "):
		c.telCmd(strings.TrimPrefix(command, "@tel "))
	case strings.HasPrefix(command, "@dump "):
		c.dumpCmd(strings.TrimPrefix(command, "@dump "))
	case strings.HasPrefix(command, "@destroy "):
		c.destroyCmd(strings.TrimPrefix(command, "@destroy "))
	case strings.HasPrefix(command, "@force "):
		c.forceCmd(command)

	default:
		if !c.goCmd(command) {
			c.output("What?\n")
		}
	}

}

func (c *ExecutionContext) lookCmd(target string) {

	if len(target) > 0 {
		object, found := c.MatchFirst(c.context.ID, target, MatchContext|MatchInventory|MatchRelative|MatchAnyType|MatchExitAliases)
		if !found {
			c.output("I don't see that here.")
			return
		}
		c.output("%s\n%s", object.DetailedName(), object.Description)
	} else {
		c.output("%s\n%s", c.context.DetailedName(), c.context.Description)
		contents := c.context.GetContents(c.actor.ID, false)
		if len(contents) > 0 {
			c.output("Contents:\n" + strings.Join(contents, "\n"))
		}
		exits := c.context.GetExits(true, false)
		if len(exits) > 0 {
			c.output("Obvious Exits:\n" + strings.Join(exits, " "))
		}
	}

}

func (c *ExecutionContext) objectName(id DBRef) string {
	o, found := c.db.Fetch(id)
	if found {
		return o.DetailedName()
	} else {
		return fmt.Sprintf("MISSING OBJECT <#%d>", id)
	}
}

func (c *ExecutionContext) examineCmd(objectName string) {

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchInventory|MatchRelative|MatchAnyType|MatchExitAliases|MatchGlobalDBRef)
	if !found {
		c.output("I don't see that here.")
		return
	}

	containerID, _ := c.db.GetParent(object.ID)

	c.output("%s", object.DetailedName())
	c.output("Type: %s", object.Type)
	c.output("@name: %s", object.Name)
	c.output("@desc: %s", object.Description)
	c.output("Next: %s", c.objectName(object.Next))
	c.output("Owner: %s", c.objectName(object.Owner))
	c.output("Location: %s", c.objectName(containerID))

	contents := object.GetContents(0, true)
	if len(contents) > 0 {
		c.output("Contains:\n%s", strings.Join(contents, "\n"))
	}

	exits := object.GetExits(false, true)
	if len(exits) > 0 {
		c.output("Exits:\n%s", strings.Join(exits, "\n"))
	}

	flags := make([]string, 0, len(object.Flags))
	for k, v := range object.Flags {
		if v {
			flags = append(flags, k)
		}
	}
	c.output("Flags: %s", strings.Join(flags, ", "))

	properties := make([]string, 0, len(object.Properties))
	for k, v := range object.Properties {
		properties = append(properties, fmt.Sprintf("@%s: %s", k, v))
	}
	c.output("Properties:\n%s", strings.Join(properties, "\n"))

}

func (c *ExecutionContext) forceCmd(input string) {

	r, _ := regexp.Compile(`^@force\pZ+([^=]*[^=\pZ]{1})\pZ*=\pZ*(.*)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	objectName, command := params[1], params[2]

	wizard := c.actor.GetFlag("wizard")

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchGlobalDBRef|MatchExitAliases|MatchInventory|MatchRelative|MatchStuffTypes)
	if !found {
		c.output("I don't see that here.")
		return
	}
	if object.Owner != c.actor.ID && !wizard {
		c.output("It's not nice to touch other people's things.")
		return
	}

	c.outbound <- PlayerEvent{src: c.actor.ID, dst: object.ID, message: command, messageType: EventTypeForce}

}

func (c *ExecutionContext) sayCmd(message string) {

	c.output(`You say "%s"`, message)
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: c.context.ID, message: message, messageType: EventTypeSay}

}

func (c *ExecutionContext) poseCmd(message string) {

	c.outbound <- PlayerEvent{src: c.actor.ID, dst: c.context.ID, message: message, messageType: EventTypePose}

}

func (c *ExecutionContext) pageCmd(input string) {

	r, _ := regexp.Compile(`^p(?:age)*\pZ+([^=]*[^=\pZ]{1})\pZ*=\pZ*(.*[^\pZ]+)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	searchName, message := params[1], params[2]

	candidate, found := c.MatchPlayerName(searchName)
	if !found {
		c.output("I don't know who you're trying to page.")
		return
	}
	if !candidate.GetFlag("online") {
		c.output("That player appears to be offline.")
		return
	}

	c.output(`You paged %s with "%s".`, candidate.ColorName(), message)
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: candidate.ID, message: message, messageType: EventTypePage}

}

func (c *ExecutionContext) inventoryCmd() {

	inventory := c.actor.GetContents(0, true)

	if len(inventory) > 0 {
		c.output("Inventory:\n %s", strings.Join(inventory, "\n "))
	} else {
		c.output("You're not carrying anything.")
	}

}

func (c *ExecutionContext) getCmd(objectName string) {

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchGlobalDBRef|MatchAnyType)
	if !found {
		c.output("I don't see that here.")
		return
	}
	if object.Type == "exit" {
		c.output("You can't pick pick up exits.")
		return
	}
	if object.Type == "player" {
		c.output("That's really annoying. Don't be that person.")
		return
	}
	if object.ID == c.actor.ID {
		c.output("You can't pick yourself up.")
		return
	}

	err := c.actor.Contains(&object)
	if err != nil {
		return
	}
	//c.actor.Refresh()
	c.output("You pick up %s.", object.ColorName())
	c.pemit(object.ID, "%s picked you up.", c.actor.ColorName())
	c.oemit(c.context.ID, "%s picks up %s.", c.actor.ColorName(), object.ColorName())

}

func (c *ExecutionContext) putCmd(input string) {
	c.xferCmd(input, "put", "into")
}

func (c *ExecutionContext) giveCmd(input string) {
	c.xferCmd(input, "give", "to")
}

func (c *ExecutionContext) xferCmd(input string, verb string, preposition string) {

	r, _ := regexp.Compile(`^` + verb + `\pZ+([^=]*[^=\pZ]{1})\pZ*` + preposition + `\pZ*(.*)\pZ*$`)

	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	objectName, receiverName := params[1], params[2]

	object, found := c.MatchFirst(c.actor.ID, objectName, MatchInventory|MatchThingType)
	if !found {
		c.output("You can't " + verb + " what you don't have.")
		return
	}
	receiver, found := c.MatchFirst(c.context.ID, receiverName, MatchContext|MatchThingType|MatchPlayerType)
	if !found {
		c.output("I cant find who or what you want to " + verb + " this " + preposition + ".")
		return
	}

	err := receiver.Contains(&object)
	if err != nil {
		return
	}

	c.output("You "+verb+" %s "+preposition+" %s.", object.ColorName(), receiver.ColorName())
	c.pemit(object.ID, "%s "+verb+"s you "+preposition+" %s.", c.actor.ColorName(), receiver.ColorName())

	if verb == "give" {
		c.pemit(receiver.ID, "%s gives you %s.", c.actor.ColorName(), object.ColorName())
	} else {
		c.pemit(receiver.ID, "%s puts %s into you.", c.actor.ColorName(), object.ColorName())
	}

}

func (c *ExecutionContext) MatchPlayerName(matchName string) (Object, bool) {
	playerMeta, foundMeta := c.db.GetPlayer(matchName)
	if foundMeta {
		o, found := c.db.Fetch(playerMeta.ID)
		if found {
			return o, true
		}
	}
	return Object{}, false
}

func (c *ExecutionContext) MatchFirst(context DBRef, matchName string, matchType int) (Object, bool) {

	wanted := map[string]bool{
		"player": matchType&MatchPlayerType != 0,
		"exit":   matchType&MatchExitType != 0,
		"room":   matchType&MatchRoomType != 0,
		"thing":  matchType&MatchThingType != 0,
	}

	if matchType&MatchRelative != 0 {
		if matchName == "here" {
			o, found := c.db.Fetch(context)
			if found && wanted[o.Type] {
				return o, true
			}
		}

		if matchName == "me" {
			if wanted[c.actor.Type] {
				return c.actor, true
			}
		}
	}

	ref, valid := NewDBRefFromHashRef(matchName)

	if valid {
		o, found := c.db.Fetch(ref)
		if found && wanted[o.Type] {
			container, _ := c.db.GetParent(o.ID)
			if container == context && matchType&MatchContext != 0 {
				return o, true
			}
			if container == c.actor.ID && matchType&MatchInventory != 0 {
				return o, true
			}
			if matchType&MatchGlobalDBRef != 0 {
				return o, true
			}
		}
	}

	if wanted["player"] && matchType&MatchGlobalPlayer != 0 {
		o, found := c.MatchPlayerName(matchName)
		if found {
			return o, true
		}
	}

	if matchType&MatchContext != 0 {
		for childID, _ := range c.db.GetChildren(context) {
			o, found := c.db.Fetch(childID)
			if found && wanted[o.Type] {
				if o.Type == "exit" && matchType&MatchExitAliases != 0 {
					aliases := strings.Split(o.Name, ";")
					for _, v := range aliases {
						if strings.EqualFold(v, matchName) {
							return o, true
						}
					}
				}
				lowerObjectName := strings.ToLower(o.Name)
				lowerMatchName := strings.ToLower(matchName)
				if strings.HasPrefix(lowerObjectName, lowerMatchName) {
					return o, true
				}
			}
		}
	}

	if matchType&MatchInventory != 0 {
		for childID, _ := range c.db.GetChildren(c.actor.ID) {
			o, found := c.db.Fetch(childID)
			if found && wanted[o.Type] {
				lowerObjectName := strings.ToLower(o.Name)
				lowerMatchName := strings.ToLower(matchName)
				if strings.HasPrefix(lowerObjectName, lowerMatchName) {
					return o, true
				}
			}
		}
	}

	return Object{}, false

}

func (c *ExecutionContext) dropCmd(objectName string) {

	object, found := c.MatchFirst(c.actor.ID, objectName, MatchInventory|MatchAnyType)
	if !found {
		c.output("You're not carrying that.")
		return
	}

	err := c.context.Contains(&object)
	if err != nil {
		return
	}

	c.output("You drop %s.", object.ColorName())
	c.pemit(object.ID, "%s drops you.", c.actor.ColorName())
	c.oemit(c.context.ID, "%s drops %s.", c.actor.ColorName(), object.ColorName())

}

func (c *ExecutionContext) enterCmd(objectName string) {

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchThingType)
	if !found {
		c.output("I don't see that here.")
		return
	}

	if object.Type == "player" {
		c.output("Maybe you should seek consent prior to entering another player.")
		return
	}
	if object.Type == "exit" {
		c.output("This s not how exits are meant to be used.")
		return
	}
	if object.ID == c.actor.ID {
		c.output("Entering yourself would be a bad idea.")
		return
	}

	if !object.GetFlag("enter_ok") && !c.actor.GetFlag("wizard") {
		c.output("You're not allowed to do that.")
		return
	}

	err := object.Contains(&c.actor)
	if err != nil {
		return
	}
	c.output("You climb into %s.", object.ColorName())
	c.oemit(c.context.ID, "%s climbs into %s.", c.actor.ColorName(), object.ColorName())
	c.oemit(object.ID, "%s squeezes into %s with you.", c.actor.ColorName(), object.ColorName())

}

func (c *ExecutionContext) leaveCmd() {

	outerObjectID, _ := c.db.GetParent(c.context.ID)
	if outerObjectID == 0 { // probably trying to 'leave' a room
		c.output("You can't leave here.")
		return
	}

	container, found := c.db.Fetch(outerObjectID)
	if !found {
		return
	}

	err := container.Contains(&c.actor)
	if err != nil {
		return
	}

	c.output("You climb out of %s.", c.context.ColorName())
	c.oemit(c.context.ID, "%s climbs out of %s.", c.actor.ColorName(), c.context.ColorName())
	c.oemit(container.ID, "%s climbs out of %s.", c.actor.ColorName(), c.context.ColorName())

}

func (c *ExecutionContext) quitCmd(connectionID int) {

	c.output("So long, it's been good to know yah.")
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: c.actor.ID, messageType: EventTypeQuit, connectionID: connectionID}

}

func (c *ExecutionContext) whoCmd() {
	onlinePlayers := c.eventDistributor.OnlinePlayers()

	c.output("Currently Online:")

	for _, ref := range onlinePlayers {
		c.output("%s", c.objectName(ref))
	}
}

func (c *ExecutionContext) createCmd(message string) {

	o := c.factory.NewThing()
	o.Name = strings.TrimSpace(message)
	o.Owner = c.actor.ID
	o.Commit()

	err := c.actor.Contains(&o)
	if err != nil {
		return
	}

	c.output("%s Created.", o.DetailedName())

}

func (c *ExecutionContext) openCmd(input string) {
	// @open <in1;in2;in3;etc>=#<room>,<out1;out2;out3;etc>

	r, _ := regexp.Compile(`^@open\pZ+([^=]*[^=\pZ]{1})\pZ*=#([0-9]+)(?:\pZ*,\pZ*([^,]*[^,\pZ]{1})\pZ*)?`)
	params := r.FindStringSubmatch(input)

	if params == nil {
		return
	}

	inExit, roomIDStr, outExit := params[1], params[2], params[3]

	if len(inExit) == 0 || len(roomIDStr) == 0 {
		c.output("Bad command or file name.")
		return
	}

	targetID, _ := NewDBRefFromString(roomIDStr) // this will never fail, the regexp guarantees that
	targetRoom, found := c.db.Fetch(targetID)
	if !found {
		c.output("Target not found.")
		return
	}

	toExit := c.factory.NewExit(inExit, targetRoom.ID, c.actor.ID)
	toExit.Commit()
	err := c.context.Contains(&toExit)
	if err != nil {
		return
	}
	c.output("%s Created.", toExit.DetailedName())

	if len(outExit) > 0 {
		fromExit := c.factory.NewExit(outExit, c.context.ID, c.actor.ID)
		fromExit.Commit()
		err = targetRoom.Contains(&fromExit)
		if err != nil {
			return
		}
		c.output("%s Created.", fromExit.DetailedName())
	}

}

func (c *ExecutionContext) digCmd(input string) {
	// @dig <Room name>=<in1;in2;in3;etc>,<out1;out2;out3;etc>
	//@dig foo bar  = <F>oo;foo;f,<B>ack;back;b

	r, _ := regexp.Compile(`^@dig\pZ+([^=]*[^=\pZ]{1})(?:\pZ*=\pZ*(?:([^,]*[^,\pZ]{1})\pZ*)?(?:\pZ*,\pZ*([^,]*[^,\pZ]{1})\pZ*)?)?`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	roomName, inExit, outExit := params[1], params[2], params[3]

	if len(roomName) == 0 {
		c.output("Rooms can't not have names.")
		return
	}

	newRoom := c.factory.NewRoom()
	newRoom.Name = roomName
	newRoom.Owner = c.actor.ID
	newRoom.Commit()

	c.output("%s Created.", newRoom.DetailedName())

	if len(inExit) > 0 || len(outExit) > 0 {
		if len(inExit) > 0 {
			toExit := c.factory.NewExit(inExit, newRoom.ID, c.actor.ID)
			toExit.Commit()
			err := c.context.Contains(&toExit)
			if err != nil {
				return
			}
			c.output("%s Created.", toExit.DetailedName())
		}
		if len(outExit) > 0 {
			fromExit := c.factory.NewExit(outExit, c.context.ID, c.actor.ID)
			fromExit.Commit()
			err := newRoom.Contains(&fromExit)
			if err != nil {
				return
			}
			c.output("%s Created.", fromExit.DetailedName())
		}
	}

}

func (c *ExecutionContext) passwordCmd(input string) {

	if c.actor.Type != "player" {
		c.output("Only players can have passwords.")
		return
	}

	r, _ := regexp.Compile(`^@password\pZ+([^\pZ]+)\pZ*=\pZ*([^\pZ]+)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	oldPassword, newPassword := params[1], params[2]

	if len(oldPassword) == 0 || len(newPassword) == 0 {
		c.output("Password can't be blank.")
		return
	}

	changed := c.db.SetPlayerPassword(c.actor.Name, oldPassword, newPassword)
	if changed {
		c.output("Password updated.")
	} else {
		c.output("Old password is wrong.")
	}

}

func (c *ExecutionContext) nameCmd(input string) {

	r, _ := regexp.Compile(`^@name\pZ+([^=]*[^=\pZ]{1})\pZ*=\pZ*(.*)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	searchName, newName := params[1], params[2]

	candidate, found := c.MatchFirst(c.context.ID, searchName, MatchContext|MatchInventory|MatchRelative|MatchGlobalDBRef|MatchExitAliases|MatchAnyType)

	if !found {
		c.output("I don't see that here.")
		return
	}

	if candidate.Type == "player" {
		i := strings.IndexFunc(newName, func(c rune) bool {
			return unicode.IsSpace(c)
		})
		if i != -1 {
			c.output("Player names can't have spaces.")
			return
		}
		if c.actor.ID != candidate.ID && !c.actor.GetFlag("wizard") {
			c.output("Only wizards can rename other players.")
			return
		}
		err := c.db.RenamePlayer(candidate.Name, newName)
		if err != nil {
			c.output("I can't do that. Something has gone wrong.")
			return
		}
	}
	candidate.Name = newName
	candidate.Commit()
	c.output("Name set.")

}

func (c *ExecutionContext) descCmd(input string) {

	r, _ := regexp.Compile(`^@desc\pZ+([^=]*[^=\pZ]{1})\pZ*=\pZ*(.*)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	objectName, description := params[1], params[2]

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchInventory|MatchRelative|MatchGlobalDBRef|MatchExitAliases|MatchAnyType)
	if !found {
		c.output("I don't see that here.")
		return
	}

	object.Description = description
	object.Commit()

	c.output("Description set.")

}

func (c *ExecutionContext) setCmd(input string) {
	r, _ := regexp.Compile(`^@set\pZ+([^=]*[^=\pZ]{1})\pZ*=\pZ*(!)?(.*)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	objectName, value, flag := params[1], params[2] != "!", params[3]

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchInventory|MatchRelative|MatchGlobalDBRef|MatchExitAliases|MatchAnyType)
	if !found {
		c.output("I don't know what that is")
		return
	}

	if object.Owner != c.actor.ID && !c.actor.GetFlag("wizard") {
		c.output("You're not allowed to do that.")
		return
	}

	object.SetFlag(flag, value)
	object.Commit()

	c.output("It is so.")

}

func (c *ExecutionContext) colorCmd(input string) {

	r, _ := regexp.Compile(`^@color\pZ+([^=]*[^=\pZ]{1})\pZ*=\pZ*([^\pZ]*)\pZ*$`)
	params := r.FindStringSubmatch(input)
	if params == nil {
		return
	}

	objectName, value := params[1], params[2]

	object, found := c.MatchFirst(c.context.ID, objectName, MatchContext|MatchInventory|MatchRelative|MatchGlobalDBRef|MatchExitAliases|MatchAnyType)

	if !found {
		c.output("I don't know what that is")
		return
	}

	if object.Owner != c.actor.ID && !c.actor.GetFlag("wizard") {
		c.output("You're not allowed to do that.")
		return
	}

	object.SetProp("color", value)
	object.Commit()

	c.output("It is so.")

}

func (c *ExecutionContext) telCmd(destStr string) {

	var dest Object
	var found bool

	dest, found = c.MatchFirst(c.context.ID, destStr, MatchGlobalDBRef|MatchRoomType)

	if !found {
		c.output("Invalid destination.")
		return
	}

	if dest.Owner != c.actor.ID && !dest.GetFlag("jump_ok") && !c.actor.GetFlag("wizard") {
		c.output("You're not allowed to do that.")
		return
	}

	c.output("You feel an intense wooshing sensation.")
	c.oemit(c.context.ID, "%s teleports out of the room.", c.actor.ColorName())
	c.oemit(dest.ID, "%s teleports in to the room.", c.actor.ColorName())

	err := dest.Contains(&c.actor)
	if err != nil {
		return
	}

	c.command("look")

}

func (c *ExecutionContext) dumpCmd(input string) {

	object, found := c.MatchFirst(c.context.ID, input, MatchContext|MatchInventory|MatchRelative|MatchGlobalDBRef|MatchGlobalPlayer|MatchExitAliases|MatchAnyType)

	if !found {
		c.output("I can't find that.")
		return
	}

	c.output("%s", c.db.DumpObject(object.ID))

}

func (c *ExecutionContext) destroyCmd(target string) {

	object, found := c.MatchFirst(c.context.ID, target, MatchContext|MatchGlobalDBRef|MatchRelative|MatchExitAliases|MatchInventory|MatchStuffTypes)
	if !found {
		c.output("I don't see that here.")
		return
	}

	if object.ID == c.actor.ID {
		c.output("There are alternatives to suicide.")
		return
	}
	if object.Type == "player" {
		c.output("I didn't think homicide was your thing.")
		return
	}

	if object.Owner != c.actor.ID && !c.actor.GetFlag("wizard") {
		c.output("You're not allowed to do that.")
		return
	}

	name := object.DetailedName()
	err := object.Delete()
	if err == nil {
		c.output("%s vanishes into thin air.", name)
	}

}

func (c *ExecutionContext) goCmd(dir string) bool {

	exit, found := c.MatchFirst(c.context.ID, dir, MatchContext|MatchExitType|MatchExitAliases)

	if !found {
		return false
	}

	if !exit.Next.Valid() {
		return false
	}

	newRoom, found := c.db.Fetch(exit.Next)
	if !found {
		c.output("That exit appears to be broken!")
		return true
	}
	err := newRoom.Contains(&c.actor)
	if err != nil {
		return false
	}
	//c.actor.Refresh()
	c.output("You head towards %s.", newRoom.DetailedName())
	c.oemit(c.context.ID, "%s leaves the room.", c.actor.ColorName())
	c.oemit(newRoom.ID, "%s enters the room.", c.actor.ColorName())
	c.command("look")
	return true
}

func (c *ExecutionContext) command(format string, a ...interface{}) {

	command := fmt.Sprintf(format, a...)
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: c.actor.ID, message: command, messageType: EventTypeCommand}

}

func (c *ExecutionContext) wall(format string, a ...interface{}) {

	message := fmt.Sprintf(format, a...)
	c.outbound <- PlayerEvent{src: c.actor.ID, message: message, messageType: EventTypeWall}

}

func (c *ExecutionContext) system(format string, a ...interface{}) {

	message := fmt.Sprintf(format, a...)
	c.outbound <- PlayerEvent{src: c.actor.ID, message: message, messageType: EventTypeSystem}

}

func (c *ExecutionContext) oemit(audience DBRef, format string, a ...interface{}) {

	message := fmt.Sprintf(format, a...)
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: audience, message: message, messageType: EventTypeOEmit}

}

func (c *ExecutionContext) output(format string, a ...interface{}) {

	message := fmt.Sprintf(format, a...)
	if !c.forceContext {
		c.outbound <- PlayerEvent{src: c.actor.ID, dst: c.actor.ID, message: message, messageType: EventTypeOutput}
	}
}

func (c *ExecutionContext) pemit(target DBRef, format string, a ...interface{}) {

	message := fmt.Sprintf(format, a...)
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: target, message: message, messageType: EventTypePEmit}

}

func (c *ExecutionContext) emit(audience DBRef, format string, a ...interface{}) {

	message := fmt.Sprintf(format, a...)
	c.outbound <- PlayerEvent{src: c.actor.ID, dst: audience, message: message, messageType: EventTypeEmit}

}