beta 2011.04.22 18:17

1 files changed, 216 insertions, 0 deletions

diff --git a/scripts/context/lua/mtx-flac.lua b/scripts/context/lua/mtx-flac.lua
new file mode 100644
index 000000000..dc7f89218
--- /dev/null
+++ b/scripts/context/lua/mtx-flac.lua
@@ -0,0 +1,216 @@
+if not modules then modules = { } end modules ['mtx-flac'] = {
+    version   = 1.001,
+    comment   = "companion to mtxrun.lua",
+    author    = "Hans Hagen, PRAGMA-ADE, Hasselt NL",
+    copyright = "PRAGMA ADE / ConTeXt Development Team",
+    license   = "see context related readme files"
+}
+
+-- Written with Within Temptation's "The Unforgiven" in loopmode on
+-- the speakers. The following code is also used for my occasional music
+-- repository cleanup session using the code below.
+
+-- this can become l-flac.lua
+
+local sub, match, byte, lower = string.sub, string.match, string.byte, string.lower
+local readstring, readnumber = io.readstring, io.readnumber
+local concat = table.concat
+local tonumber = tonumber
+local tobitstring = number.tobitstring
+
+flac = flac or { }
+
+flac.report = string.format
+
+local splitter = lpeg.splitat("=")
+local readers  = { }
+
+readers[0] = function(f,size,target) -- not yet ok
+    local info = { }
+    target.info = info
+    info.minimum_block_size = readnumber(f,-2)
+    info.maximum_block_size = readnumber(f,-2)
+    info.minimum_frame_size = readnumber(f,-3)
+    info.maximum_frame_size = readnumber(f,-3)
+    local buffer = { }
+    for i=1,8 do
+        buffer[i] = tobitstring(readnumber(f,1))
+    end
+    local bytes = concat(buffer)
+    info.sample_rate_in_hz  = tonumber(sub(bytes, 1,20),2) -- 20
+    info.number_of_channels = tonumber(sub(bytes,21,23),2) --  3
+    info.bits_per_sample    = tonumber(sub(bytes,24,28),2) --  5
+    info.samples_in_stream  = tonumber(sub(bytes,29,64),2) -- 36
+    info.md5_signature = readstring(f,16) -- 128
+end
+
+readers[4] = function(f,size,target,banner)
+    local tags = { }
+    target.tags = tags
+    target.vendor = readstring(f,readnumber(f,-4))
+    for i=1,readnumber(f,-4) do
+        local key, value = lpeg.match(splitter,readstring(f,readnumber(f,-4)))
+        tags[lower(key)] = value
+    end
+end
+
+readers.default = function(f,size,target)
+    f:seek("cur",size)
+end
+
+function flac.getmetadata(filename)
+    local f = io.open(filename, "rb")
+    if f then
+        local banner = readstring(f,4)
+        if banner == "fLaC" then
+            local data = {
+                banner   = banner,
+                filename = filename,
+                filesize = lfs.attributes(filename,"size"),
+            }
+            while true do
+                local flag = readnumber(f,1)
+                local size = readnumber(f,3)
+                local last = flag > 127
+                if last then
+                    flag = flag - 128
+                end
+                local reader = readers[flag] or readers.default
+                reader(f,size,data,banner)
+                if last then
+                    return data
+                end
+            end
+        else
+            flac.report("no flac file: %s (%s)",filename,banner)
+        end
+        f:close()
+    else
+        flac.report("no file: %s",filename)
+    end
+end
+
+function flac.savecollection(pattern,filename)
+    pattern = (pattern ~= "" and pattern) or "**/*.flac"
+    filename = (filename ~= "" and filename) or "music-collection.xml"
+    flac.report("identifying files using pattern %q" ,pattern)
+    local files = dir.glob(pattern)
+    flac.report("%s files found, analyzing files",#files)
+    local music = { }
+    for i=1,#files do
+        local data = flac.getmetadata(files[i])
+        if data then
+            local tags = data.tags
+            local info = data.info
+            local artist = tags.artist
+            local album = tags.album
+            local albums = music[artist]
+            if not albums then
+                albums = { }
+                music[artist] = albums
+            end
+            local albumx = albums[album]
+            if not albumx then
+                albumx = {
+                    year   = tags.date,
+                    tracks = { },
+                }
+                albums[album] = albumx
+            end
+            albumx.tracks[tonumber(tags.tracknumber) or 0] = {
+                title  = tags.title,
+                length = math.round((info.samples_in_stream/info.sample_rate_in_hz)),
+            }
+        end
+    end
+ -- inspect(music)
+    local nofartists, nofalbums, noftracks, noferrors = 0, 0, 0, 0
+    local f = io.open(filename,"wb")
+    if f then
+        f:write("<?xml version='1.0' standalone='yes'?>\n\n")
+        f:write("<collection>\n")
+        for artist, albums in table.sortedpairs(music) do
+            nofartists = nofartists + 1
+            f:write("\t<artist>\n")
+            f:write("\t\t<name>" .. artist .. "</name>\n")
+            f:write("\t\t\t<albums>\n")
+            for album, data in table.sortedpairs(albums) do
+                nofalbums = nofalbums + 1
+                f:write("\t\t\t\t<album year='" .. (data.year or 0) .. "'>\n")
+                f:write("\t\t\t\t\t<name>" .. album .. "</name>\n")
+                f:write("\t\t\t\t\t<tracks>\n")
+                local tracks = data.tracks
+                for i=1,#tracks do
+                    local track = tracks[i]
+                    if track then
+                        noftracks = noftracks + 1
+                        f:write("\t\t\t\t\t\t<track length='" .. track.length .. "'>" .. track.title .. "</track>\n")
+                    else
+                        noferrors = noferrors + 1
+                        flac.report("error in album: %q of artist",album,artist)
+                        f:write("\t\t\t\t\t\t<error track='" .. i .. "'/>\n")
+                    end
+                end
+                f:write("\t\t\t\t\t</tracks>\n")
+                f:write("\t\t\t\t</album>\n")
+            end
+            f:write("\t\t\t</albums>\n")
+            f:write("\t\t</artist>\n")
+        end
+        f:write("</collection>\n")
+    end
+    f:close()
+    flac.report("%s tracks of %s albums of %s artists saved in %q (%s errors)",noftracks,nofalbums,nofartists,filename,noferrors)
+end
+
+--
+
+local helpinfo = [[
+--collect             collect albums in xml file
+
+example:
+
+mtxrun --collect somename.flac
+mtxrun --collect --pattern="m:/music/**")
+]]
+
+local application = logs.application {
+    name     = "mtx-flac",
+    banner   = "ConTeXt Flac Helpers 0.10",
+    helpinfo = helpinfo,
+}
+
+flac.report = application.report
+
+-- script code
+
+scripts      = scripts      or { }
+scripts.flac = scripts.flac or { }
+
+function scripts.flac.collect()
+    local files   = environment.files
+    local pattern = environment.arguments.pattern
+    if #files > 0 then
+        for i=1,#files do
+            local filename = files[1]
+            if file.suffix(filename) == "flac" then
+                flac.savecollection(filename,file.replacesuffix(filename,"xml"))
+            elseif lfs.isdir(filename) then
+                local pattern = filename .. "/**.flac"
+                flac.savecollection(pattern,file.addsuffix(file.basename(filename),"xml"))
+            else
+                flac.savecollection(file.replacesuffix(filename,"flac"),file.replacesuffix(filename,"xml"))
+            end
+        end
+    elseif pattern then
+        flac.savecollection(file.addsuffix(pattern,"flac"),"music-collection.xml")
+    else
+        flac.report("no file(s) or pattern given" )
+    end
+end
+
+if environment.argument("collect") then
+    scripts.flac.collect()
+else
+    application.help()
+end