Fix files so that they are validated by the schema

Liber Usualis - mei3/liberupdatev5.py

@@ -0,0 +1,240 @@
+import lxml.etree as ET
+
+def main(filename: str) -> None:
+    """
+    Converts an MEI file to MEI 5.0 format.
+
+    Args:
+        filename: The path to the MEI file to be converted.
+    """
+    ET.register_namespace("mei", "http://www.music-encoding.org/ns/mei")
+
+    tree = ET.parse(filename)
+    root = tree.getroot()
+
+    # Dictionaries for mapping attribute values
+    div_dict = {"minor": "maior", "minior": "maior", "major": "maxima", "final": "finalis", "small": "minima", "comma": "virgula"}
+    epi_dict = {"horizontal": "h", "vertical": "v"}
+
+    # Flags for tracking certain conditions
+    theres_an_episema = False
+    theres_a_pb = False
+    theres_a_sb = False
+    nc_flag = False
+    neume_flag = False
+
+    # Extra attributes for neumes and notes
+    extra_nc = {}
+    extra_neume = {}
+
+    # Set MEI version to 5.0
+    root.attrib["meiversion"] = "5.0"
+
+    # Iterate over all elements in the tree
+    for child in root.iter("*"):
+        child.tag = ET.QName(child).localname
+
+        # Handle graphic elements (e.g., change href to target)
+        if child.tag.endswith("graphic"): #changes some stuff in the headers
+            for att in list(child.attrib):
+                if att.endswith("href"):                    
+                    child.attrib('target', child.attrib.pop(att))
+
+        # Handle page breaks
+        elif child.tag.endswith("pb"): #adds in pagebreak info from layout element (which gets deleted later)
+            child.tag = "peeb"
+            for att in child.attrib:                
+                if att.endswith("pageref"):                    
+                    pageref = child.attrib.pop(att)
+                    break
+            for child_2 in root.iter():
+              for attr, value in child_2.attrib.items():               
+                if attr.endswith("id") and value == pageref:
+                        child.set("n", child_2.attrib["n"])
+                        break                 
+            pa_bre = ET.tostring(child)
+            theres_a_pb = True
+            child.tag = "TODELETE"
+
+        # Handle system breaks
+        elif child.tag.endswith("sb"):
+            child.tag = "seeb"
+            for att in child.attrib:
+                if att.endswith("systemref"):                    
+                    systemref = child.attrib.pop(att)
+                    break
+            for child_2 in root.iter():               
+              for attr, value in child_2.attrib.items():
+                if attr.endswith("id") and value == systemref:
+                        child.set("facs", child_2.attrib["facs"])
+                        break
+            sy_bre = ET.tostring(child)           
+            theres_a_sb = True
+            child.tag = "TODELETE"
+
+        # Moves system breaks and page breaks inside layer
+        elif child.tag.endswith("layer"):
+            if theres_a_pb:
+                theres_a_pb = False
+                child.append(ET.fromstring(pa_bre))
+            if theres_a_sb:
+                theres_a_sb = False
+                child.append(ET.fromstring(sy_bre))
+
+        # Handle zone elements (adjusts negative ulx and lrx attributes)
+        elif child.tag.endswith("zone"):
+            label = ""
+            for attr, value in child.attrib.items():
+                if attr.endswith("ulx") and int(value) < 0:
+                    label = f"{label} ulx = {value} "
+                    child.set("label", label)
+                    child.set(attr, "0")
+                    break
+            for attr, value in child.attrib.items():
+                if attr.endswith("lrx") and int(value) < 0:
+                    label = f"{label} ulx = {value} "
+                    child.set("label", label)
+                    child.set(attr, "0")
+                    break
+
+        # Handle dot elements (temporary fix until morae get added to MEI)
+        elif child.tag.endswith("dot"):
+            child.tag = "signifLet"
+            for att in child.attrib:
+                if att.endswith("form"):
+                    child.attrib.pop(att)
+                    break
+
+        # Handle neume elements (become syllables, ncs become neumes, and notes become ncs)
+        elif child.tag.endswith("neume"):
+            _syl = ET.SubElement(child, "syl")
+            extra_neume= dict(child.attrib)
+            child.attrib.clear()
+            neume_flag = True
+            for att in extra_neume:
+                if att.endswith("name"):                    
+                    child.set('type', extra_neume.pop(att))
+                    break
+            for att in extra_neume:
+                if att.endswith("variant"):                    
+                    child.set('type',  child.attrib['type'] + extra_neume.pop(att))
+                    break
+            for att in extra_neume:
+                if att.endswith("id"):                    
+                    child.set(att, extra_neume.pop(att))
+                    break
+
+        #Handle nc elements
+        elif child.tag.endswith("nc"):
+            extra_nc = dict(child.attrib)
+            child.attrib.clear()
+            nc_flag = True
+            if neume_flag:
+                neume_flag = False
+                child.attrib.update(extra_neume)
+            for att in extra_nc:
+                if att.endswith("id"):                    
+                    child.set(att, extra_nc.pop(att))
+                    break
+
+        # Handle division elements (become divLine)
+        elif child.tag.endswith("division"):
+            for att, value in child.attrib.items():
+                if att.endswith("form"):
+                    child.set(att, div_dict[value])
+
+        # Handle note elements
+        elif child.tag.endswith("note"):
+            if nc_flag:
+                nc_flag = False
+                child.attrib.update(extra_nc)
+            for att, value in child.attrib.items():
+                if att.endswith("inclinatum"):
+                    child.set("tilt", "se")
+                    child.attrib.pop(att)
+                    break
+            for att in child.attrib:
+                if att.endswith("quilisma"):
+                    child.attrib.pop(att)
+                    _quil = ET.SubElement(child, "quilisma")
+                    break
+            if theres_an_episema:
+                theres_an_episema = False
+                child.append(ET.fromstring(epis))
+
+        # Handle accid elements (remove oct and pname attributes)
+        elif child.tag.endswith("accid"):
+            for att in child.attrib:
+                if att.endswith("oct"):
+                    child.attrib.pop(att)
+                    break
+            for att in child.attrib:
+                if att.endswith("pname"):
+                    child.attrib.pop(att)
+                    break
+
+        # Handle episema elements
+        elif child.tag.endswith("episema"):
+            child.tag = "apisema"
+            theres_an_episema = True
+            for att, value in child.attrib.items():
+                if att.endswith("form"):
+                    child.set(att, epi_dict[value])
+            for att in child.attrib:
+                if att.endswith("startid"):
+                    child.attrib.pop(att)
+                    break
+            for att in child.attrib:
+                if att.endswith("endid"):
+                    child.attrib.pop(att)
+                    break
+            epis = ET.tostring(child)
+            child.tag = "TODELETE"
+
+
+    # Create a new root element with MEI 5.0 namespace
+    new_root = ET.Element(root.tag)
+    new_root.attrib["xmlns"] = "http://www.music-encoding.org/ns/mei"
+    new_root.attrib["meiversion"] = "5.0"
+
+    # Create processing instructions
+    pi1 = ET.ProcessingInstruction('xml-model', 'href="https://music-encoding.org/schema/5.0/mei-all.rng" type="application/xml" schematypens="http://relaxng.org/ns/structure/1.0"')
+    pi2 = ET.ProcessingInstruction('xml-model', 'href="https://music-encoding.org/schema/5.0/mei-all.rng" type="application/xml" schematypens="http://purl.oclc.org/dsdl/schematron"')
+
+    # Add processing instructions to the tree
+    new_root.addprevious(pi1)
+    new_root.addprevious(pi2)
+
+    # Recursively build the new tree
+    stack = [(new_root, root)]
+    while stack:
+        new_element, old_element = stack.pop()
+        for child in old_element:
+            tag = child.tag
+            if tag.endswith("layout"):  # delete some elements
+                continue
+            if tag.endswith("TODELETE"):
+                continue
+
+            if tag.endswith("neume"):  # rename some others
+                tag = "syllable"
+            elif tag.endswith("nc"):
+                tag = "neume"
+            elif tag.endswith("note"):
+                tag = "nc"
+            elif tag.endswith("apisema"):
+                tag = "episema"
+            elif tag.endswith("peeb"):
+                tag = "pb"
+            elif tag.endswith("seeb"):
+                tag = "sb"
+            elif tag.endswith("division"):
+                tag = "divLine"
+
+            new_child = ET.Element(tag, child.attrib)
+            new_element.append(new_child)
+            stack.append((new_child, child))
+
+    # Write the new tree to a file
+    new_tree = ET.ElementTree(new_root)
+    new_tree.write(filename[:-4] + " - mei5.mei", encoding="utf8", xml_declaration=True)