Merge branch 'release/luau-scripting' into lua-speedometer-demo

1 files changed, 101 insertions, 0 deletions

diff --git a/indra/newview/scripts/lua/timers.lua b/indra/newview/scripts/lua/timers.lua
new file mode 100644
index 0000000000..e0d27a680d
--- /dev/null
+++ b/indra/newview/scripts/lua/timers.lua
@@ -0,0 +1,101 @@
+-- Access to the viewer's time-delay facilities
+
+local leap = require 'leap'
+
+local timers = {}
+
+local function dbg(...) end
+-- local dbg = require 'printf'
+
+timers.Timer = {}
+
+-- delay:    time in seconds until callback
+-- callback: 'wait', or function to call when timer fires (self:tick if nil)
+-- iterate:  if non-nil, call callback repeatedly until it returns non-nil
+--           (ignored if 'wait')
+function timers.Timer:new(delay, callback, iterate)
+    local obj = setmetatable({}, self)
+    self.__index = self
+
+    if callback == 'wait' then
+        dbg('scheduleAfter(%d):', delay)
+        sequence = leap.generate('Timers', {op='scheduleAfter', after=delay})
+        -- ignore the immediate return
+        dbg('scheduleAfter(%d) -> %s', delay,
+        sequence.next())
+        -- this call is where we wait for real
+        dbg('next():')
+        dbg('next() -> %s',
+        sequence.next())
+        sequence.done()
+        return
+    end
+
+    callback = callback or function() obj:tick() end
+
+    local first = true
+    if iterate then
+        obj.id = leap.eventstream(
+            'Timers',
+            {op='scheduleEvery', every=delay},
+            function (event)
+                local reqid = event.reqid
+                if first then
+                    first = false
+                    dbg('timer(%s) first callback', reqid)
+                    -- discard the first (immediate) response: don't call callback
+                    return nil
+                else
+                    dbg('timer(%s) nth callback', reqid)
+                    return callback(event)
+                end
+            end
+        ).reqid
+    else
+        obj.id = leap.eventstream(
+            'Timers',
+            {op='scheduleAfter', after=delay},
+            function (event)
+                -- Arrange to return nil the first time, true the second. This
+                -- callback is called immediately with the response to
+                -- 'scheduleAfter', and if we immediately returned true, we'd
+                -- be done, and the subsequent timer event would be discarded.
+                if first then
+                    first = false
+                    -- Caller doesn't expect an immediate callback.
+                    return nil
+                else
+                    callback(event)
+                    -- Since caller doesn't want to iterate, the value
+                    -- returned by the callback is irrelevant: just stop after
+                    -- this one and only call.
+                    return true
+                end
+            end
+        ).reqid
+    end
+
+    return obj
+end
+
+function timers.Timer:tick()
+    error('Pass a callback to Timer:new(), or override Timer:tick()')
+end
+
+function timers.Timer:cancel()
+    local ok = leap.request('Timers', {op='cancel', id=self.id}).ok
+    leap.cancelreq(self.id)
+    return ok
+end
+
+function timers.Timer:isRunning()
+    return leap.request('Timers', {op='isRunning', id=self.id}).running
+end
+
+-- returns (true, seconds left) for a live timer, else (false, 0)
+function timers.Timer:timeUntilCall()
+    local result = leap.request('Timers', {op='timeUntilCall', id=self.id})
+    return result.ok, result.remaining
+end
+
+return timers