First pass at tagging and report functions.

1 files changed, 99 insertions, 0 deletions

diff --git a/ugbudget/ugbudget.py b/ugbudget/ugbudget.py
new file mode 100644
index 0000000..f75a444
--- /dev/null
+++ b/ugbudget/ugbudget.py
@@ -0,0 +1,99 @@
+import argparse
+import collections
+import csv
+import gnucashxml
+import os
+import sys
+from decimal import Decimal
+
+def main():
+    parser = argparse.ArgumentParser(description='The Usable GnuCash Budget Tool')
+
+    cmd_group = parser.add_mutually_exclusive_group(required=True)
+    cmd_group.add_argument('--create-tags', action='store_true',
+                           help='Update tags-file with any unmapped accounts')
+    cmd_group.add_argument('--report', action='store_true',
+                           help='Produce a budget vs. actuals report')
+    parser.add_argument('tags_file', metavar='tags-file',
+                        help='The mapping of GnuCash accounts to budget tags')
+    parser.add_argument('data_file', metavar='gnucash-file',
+                        help='The GnuCash data file to process')
+
+    args = parser.parse_args()
+
+    book = gnucashxml.from_filename(args.data_file)
+
+    if args.create_tags:
+        create_tags(book, args.tags_file)
+    elif args.report:
+        report(book, args.tags_file)
+
+def read_tags(filename):
+    '''
+    Read a TSV file where each row maps a GnuCash account to a tag. A tag is
+    one or more tab-separated values which are treated as budget categories,
+    subcategories, etc.
+    '''
+    tag_header = ('category',)
+    tags = {}
+    if os.path.isfile(filename):
+        with open(filename, 'rb') as f:
+            reader = csv.reader(f, csv.excel_tab)
+            for row in reader:
+                if row[0] == "account":
+                    tag_header = row[1:]
+                else:
+                    tags[row[0]] = tuple(row[1:])
+    return (tag_header, tags)
+
+def write_tags(filename, tag_header, tags):
+    '''
+    Write a tags file as described by read_tags().
+    '''
+    with open(filename, 'wb') as f:
+        writer = csv.writer(f, csv.excel_tab)
+        writer.writerow(['account'] + list(tag_header))
+        for account in sorted(tags):
+            writer.writerow([account] + list(tags[account]))
+
+def create_tags(book, tags_file):
+    '''
+    Read a GnuCash data file and add any new, unmapped accounts to tags_file.
+    '''
+    (tag_header, tags) = read_tags(tags_file)
+    for (acc, children, splits) in book.walk():
+        if not children:
+            if acc.actype == "INCOME" or acc.actype == "EXPENSE":
+                acc_name = gnucash_account_fullname(acc)
+                if acc_name not in tags:
+                    tags[acc_name] = tag_header
+    write_tags(tags_file, tag_header, tags)
+
+def report(book, tags_file):
+    (tag_header, tags) = read_tags(tags_file)
+    report = collections.defaultdict(lambda: collections.defaultdict(Decimal))
+    for (acc, children, splits) in book.walk():
+        acc_name = gnucash_account_fullname(acc)
+        if acc_name in tags:
+            mapping = tuple([acc.actype] + list(tags[acc_name]))
+            for split in splits:
+                date = split.transaction.date.strftime("%Y-%m-01")
+                report[date][mapping] += split.value.copy_negate()
+
+    writer = csv.writer(sys.stdout, csv.excel_tab)
+    writer.writerow(['month', 'account_type'] + list(tag_header) + ['value'])
+    for month in sorted(report):
+        for (mapping, value) in report[month].iteritems():
+            writer.writerow([month] + list(mapping) + [value])
+
+def gnucash_account_fullname(acc, partial=''):
+    if acc.parent:
+        if partial:
+            partial = "%s:%s" % (acc.name, partial)
+        else:
+            partial = acc.name
+        return gnucash_account_fullname(acc.parent, partial)
+    else:
+        return partial
+
+main()