Implemented quest variables.

1 files changed, 75 insertions, 35 deletions

diff --git a/data/scripts/libtmw.lua b/data/scripts/libtmw.lua
index bb724799..3189da6a 100644
--- a/data/scripts/libtmw.lua
+++ b/data/scripts/libtmw.lua
@@ -8,10 +8,12 @@ local npcs = {}
 
 -- Table that associates to each Character pointer its state with respect to
 -- NPCs (only one at a time). A state is an array with four fields:
--- . 1: pointer of the NPC the player is currently talking to.
+-- . 1: pointer to the NPC the player is currently talking to.
 -- . 2: coroutine running the NPC handler.
--- . 3: next query the NPC expects from a player (1 = next, 2 = choice).
+-- . 3: next event the NPC expects from the server.
+--      (1 = npc_next, 2 = npc_choose, 3 = quest_reply, 4 = 1+3)
 -- . 4: countdown (in minutes) before the state is deleted.
+-- . 5: name of the expected quest variable. (optional)
 local states = {}
 
 -- Array containing the function registered by atinit.
@@ -46,34 +48,68 @@ function do_choice(npc, ch, ...)
   return coroutine.yield(2)
 end
 
+-- Gets the value of a quest variable.
+-- Calling this function while an acknowledment is pending is desirable, so
+-- that lag cannot be perceived by the player.
+function get_quest_var(npc, ch, name)
+  -- Query the server and return immediatly if a value is available.
+  local value = tmw.chr_get_quest(ch, name)
+  if value then return value end
+  -- Wait for database reply.
+  return coroutine.yield(3, name)
+end
+
 -- Processes as much of an NPC handler as possible.
-local function process_npc(co, ...)
-  -- First, resume with the arguments the coroutine was waiting for.
-  local b, v = coroutine.resume(co, ...)
-  if not b or not v then
-    return
-  end
-  if v == 2 then
-    return 2
-  end
-  -- Then, keep resuming until the coroutine expects the result of a choice
-  -- or an acknowledgment to a message.
-  local pending = (v == 1)
+local function process_npc(w, ...)
+  local co = w[2]
+  local pending = (w[3] == 4)
+  local first = true
   while true do
-    b, v = coroutine.resume(co)
+    local b, v, u
+    if first then
+      -- First time, resume with the arguments the coroutine was waiting for.
+      b, v, u = coroutine.resume(co, ...)
+      first = false
+    else
+      -- Otherwise, simply resume.
+      b, v, u = coroutine.resume(co)
+    end
     if not b or not v then
+      -- Either there was an error, or the handler just finished its work.
       return
     end
     if v == 2 then
-      return 2
+      -- The coroutine needs a user choice from the server, so wait for it.
+      w[3] = 2
+      break
+    end
+    if v == 3 then
+      -- The coroutine needs the value of a quest variable from the server.
+      w[5] = u
+      if pending then
+        -- The coroutine has also sent a message to the user, so do not
+        -- forget about it, as it would flood the user with new messages.
+        w[3] = 4
+      else
+        w[3] = 3
+      end
+      break
     end
     if pending then
-      return 1
+      -- The coroutine is about to interact with the user. But the previous
+      -- action has not been acknowledged by the user yet, so wait for it.
+      w[3] = 1
+      break
     end
     if v == 1 then
+      -- A message has just been sent. But the coroutine can keep going in case
+      -- there is still some work to do while waiting for user acknowledgment.
       pending = true
     end
   end
+  -- Restore the countdown, as there was some activity.
+  w[4] = 5
+  return true
 end
 
 -- Called by the game whenever a player starts talking to an NPC.
@@ -82,10 +118,9 @@ function npc_start(npc, ch)
   states[ch] = nil
   local h = npcs[npc]
   if not h then return end
-  local co = coroutine.create(h)
-  local v = process_npc(co, npc, ch)
-  if v then
-    states[ch] = {npc, co, v, 5}
+  local w = { npc, coroutine.create(h) }
+  if process_npc(w, npc, ch) then
+    states[ch] = w
     if not timer then
       timer = 600
     end
@@ -96,27 +131,32 @@ end
 -- Checks that the NPC expects it, and processes the respective coroutine.
 function npc_next(npc, ch)
   local w = states[ch]
-  if w and w[1] == npc and w[3] == 1 then
-    local v = process_npc(w[2])
-    if v then
-      w[3] = v
-      w[4] = 5
-      return
-    end
+  if not (w and w[1] == npc and w[3] == 1 and process_npc(w)) then
+    states[ch] = nil
   end
-  states[ch] = nil
 end
 
 -- Called by the game whenever a player selects a particular reply.
 -- Checks that the NPC expects it, and processes the respective coroutine.
 function npc_choose(npc, ch, u)
   local w = states[ch]
-  if w and w[1] == npc and w[3] == 2 then
-    local v = process_npc(w[2], u)
-    if v then
-      w[3] = v
-      w[4] = 5
-      return
+  if not (w and w[1] == npc and w[3] == 2 and process_npc(w, u)) then
+    states[ch] = nil
+  end
+end
+
+-- Called by the game whenever the value of a quest variable is known.
+-- Checks that the NPC expects it, and processes the respective coroutine.
+-- Note: the check for NPC correctness is missing, but it should never matter.
+function quest_reply(ch, name, value)
+  local w = states[ch]
+  if w then
+    local w3 = w[3]
+    if (w3 == 3 or w3 == 4) and w[5] == name then
+      w[5] = nil
+      if process_npc(w, value) then
+        return
+      end
     end
   end
   states[ch] = nil