DFHack · lethosor · Nov 27, 2016 · Nov 22, 2016 · Nov 22, 2016
diff --git a/season-palette.lua b/season-palette.lua
@@ -0,0 +1,221 @@
+-- Swap color palettes with the changes of the seasons.
+-- 
+-- Based on my script for the Rubble addon "Libs/Colors/Swap Palette", modified at
+-- Meph's request to support automatic seasonal switching.
+
+--[[
+Copyright 2016 Milo Christiansen
+
+This software is provided 'as-is', without any express or implied warranty. In
+no event will the authors be held liable for any damages arising from the use of
+this software.
+
+Permission is granted to anyone to use this software for any purpose, including
+commercial applications, and to alter it and redistribute it freely, subject to
+the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not claim
+that you wrote the original software. If you use this software in a product, an
+acknowledgment in the product documentation would be appreciated but is not
+required.
+
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+
+3. This notice may not be removed or altered from any source distribution.
+]]
+
+--@ module = true
+--@ enable = true
+
+local mappingsA = {
+    ["BLACK"] = 0,
+    ["BLUE"] = 1,
+    ["GREEN"] = 2,
+    ["CYAN"] = 3,
+    ["RED"] = 4,
+    ["MAGENTA"] = 5,
+    ["BROWN"] = 6,
+    ["LGRAY"] = 7,
+    ["DGRAY"] = 8,
+    ["LBLUE"] = 9,
+    ["LGREEN"] = 10,
+    ["LCYAN"] = 11,
+    ["LRED"] = 12,
+    ["LMAGENTA"] = 13,
+    ["YELLOW"] = 14,
+    ["WHITE"] = 15,
+}
+
+local mappingsB = {
+    ["R"] = 0,
+    ["G"] = 1,
+    ["B"] = 2,
+}
+
+local function trimPrefix(pre, str)
+    if (string.find(str, pre, 1, true)) ~= 1 then return str end
+    return string.sub(str, #pre + 1)
+end
+
+function LoadPalette(path)
+    -- Strip off the DF path (if it is included) so the log message is shorter.
+    print("Attempting to load color palette file: \""..trimPrefix(dfhack.getDFPath(), path).."\"")
+
+    local file, err = io.open(path, "rb")
+    if file == nil then
+        -- Use a less verbose error message to keep the console cleaner.
+        --print("  Load failed: "..err)
+        print("  Could not open file.")
+        return false
+    end
+
+    local contents = file:read("*a")
+    file:close()
+
+    -- Keep track of the old colors so we can revert to them if we have trouble parsing the new color file.
+    local revcolors = {}
+    for a = 0, 15, 1 do
+        revcolors[a] = {}
+        for b = 0, 2, 1 do
+            revcolors[a][b] = df.global.enabler.ccolor[a][b]
+        end
+    end
+
+    -- If only I could use the Rubble raw parser here... Oh well, I suppose regular expressions will do almost as well.
+    for a, b, v in string.gmatch(contents, "%[([A-Z]+)_([RGB]):([0-9]+)%]") do
+        local ka, kb, v = mappingsA[a], mappingsB[b], tonumber(v)
+        if ka == nil or kb == nil or v == nil then
+            -- Parse error, revert changes.
+            for x = 0, 15, 1 do
+                for y = 0, 2, 1 do
+                    df.global.enabler.ccolor[x][y] = revcolors[x][y]
+                end
+            end
+            print("  Color file parse error (all changes reverted).")
+            return false
+        end
+
+        if v == 0 then
+            df.global.enabler.ccolor[ka][kb] = 0
+        else
+            v = v / 255
+            if v > 1 then
+                print("  Warning: The "..b.." component for color "..a.." is out of range! Adjusting value.")
+                v = 1
+            end
+            df.global.enabler.ccolor[ka][kb] = v
+        end
+    end
+    return true
+end
+
+if moduleMode then return end
+
+function usage()
+    print [==[
+Swap color palettes when the seasons change.
+
+For this script to work you need to add *at least* one color palette file to
+your save raw directory.
+
+Palette file names:
+    "colors.txt": The world "default" (worldgen and replacement) palette.
+    "colors_spring.txt": The palette displayed during spring.
+    "colors_summer.txt": The palette displayed during summer.
+    "colors_autumn.txt": The palette displayed during autumn.
+    "colors_winter.txt": The palette displayed during winter.
+
+If you do not provide a world default palette, palette switching will be
+disabled for the current world. The seasonal palettes are optional, the default
+palette is not! The default palette will be used to replace any missing
+seasonal palettes and during worldgen.
+
+When the world is unloaded or this script is disabled, the system default color
+palette ("/data/init/colors.txt") will be loaded. The system default palette
+will always be used in the main menu, but your custom palettes should be used
+everywhere else.
+
+Usage:
+    season-palette start|enable
+    enable season-palette
+        Begin swapping seasonal color palettes.
+
+    season-palette stop|disable
+    disable season-palette
+        Stop swapping seasonal color palettes and load the default color
+        palette.
+
+    If loaded as a module this script will export a single Lua function:
+
+    LoadPalette(path)
+        Load a color palette from the text file at "path". This file must be in
+        the same format as "/data/init/colors.txt". If there is an error any
+        changes will be reverted and this function will return false (returns
+        true normally).
+]==]
+end
+
+args = {...}
+if dfhack_flags and dfhack_flags.enable then
+    table.insert(args, dfhack_flags.enable_state and 'enable' or 'disable')
+end
+
+enabled = false
+if #args >= 1 then
+    if args[1] == 'start' or args[1] == 'enable' then
+        enabled = true
+    elseif args[1] == 'stop' or args[1] == 'disable' then
+        enabled = false
+    else
+        usage()
+        return
+    end
+else
+    usage()
+    return
+end
+
+local seasons = {
+    [-1] = '', -- worldgen
+    [0] = '_spring',
+    [1] = '_summer',
+    [2] = '_autumn',
+    [3] = '_winter',
+}
+lastSeason = lastSeason or nil
+
+local function seasonSwapLoop()
+    if not enabled then
+        LoadPalette(dfhack.getDFPath().."/data/init/colors.txt")
+        return
+    end
+
+    if lastSeason == nil or lastSeason ~= df.global.cur_season then
+        lastSeason = df.global.cur_season
+
+        -- Try to load the seasonal palette, if that fails fall back on the world default palette.
+        if not LoadPalette(dfhack.getSavePath().."/raw/colors"..seasons[lastSeason]..".txt") then
+            if seasons[lastSeason] == "" or not LoadPalette(dfhack.getSavePath().."/raw/colors.txt") then
+                print("The current world do not provide a valid default palette, disabling palette swapping for this world.")
+                return
+            end
+        end
+    end
+
+    dfhack.timeout(50, 'ticks', seasonSwapLoop)
+end
+
+dfhack.onStateChange.SeasonPalette = function(event)
+    if event == SC_WORLD_LOADED and enabled then
+        seasonSwapLoop()
+    end
+    if event == SC_WORLD_UNLOADED and enabled then
+        LoadPalette(dfhack.getDFPath().."/data/init/colors.txt")
+        -- Ticker is auto-canceled by DFHack.
+    end
+end
+
+if dfhack.isWorldLoaded() then
+    dfhack.onStateChange.SeasonPalette(SC_WORLD_LOADED)
+end