+from http.server import BaseHTTPRequestHandler, HTTPServer
+import sys
+hostName = "localhost"
+serverPort = 8082
+
+
+class HandledException(Exception):
+ pass
+
+
+def handled_error_exit(msg):
+ print(f"ERROR: {msg}")
+ sys.exit(1)
+
+
+def apply_booking_to_account_balances(account_sums, account, currency, amount):
+ if not account in account_sums:
+ account_sums[account] = {currency: amount}
+ elif not currency in account_sums[account].keys():
+ account_sums[account][currency] = amount
+ else:
+ account_sums[account][currency] += amount
+
+
+class Booking:
+
+ def __init__(self, date_string, description, booking_lines, start_line):
+ self.date_string = date_string
+ self.description = description
+ self.lines = booking_lines
+ self.start_line = start_line
+ self.validate_booking_lines()
+ self.account_changes = self.parse_booking_lines_to_account_changes()
+
+ def validate_booking_lines(self):
+ prefix = f"booking at line {self.start_line}"
+ sums = {}
+ empty_values = 0
+ for line in self.lines:
+ if line == '':
+ continue
+ _, amount, currency = line
+ if amount is None:
+ if empty_values > 0:
+ raise HandledException(f"{prefix} relates more than one empty value of same currency {currency}")
+ empty_values += 1
+ continue
+ if currency not in sums:
+ sums[currency] = 0
+ sums[currency] += amount
+ if empty_values == 0:
+ for k, v in sums.items():
+ if v != 0:
+ raise HandledException(f"{prefix} does not sum up to zero")
+ else:
+ sinkable = False
+ for k, v in sums.items():
+ if v != 0:
+ sinkable = True
+ if not sinkable:
+ raise HandledException(f"{prefix} has empty value that cannot be filled")
+
+ def parse_booking_lines_to_account_changes(self):
+ account_changes = {}
+ debt = {}
+ sink_account = None
+ for line in self.lines:
+ if line == '':
+ continue
+ account, amount, currency = line
+ if amount is None:
+ sink_account = account
+ continue
+ apply_booking_to_account_balances(account_changes, account, currency, amount)
+ if currency not in debt:
+ debt[currency] = amount
+ else:
+ debt[currency] += amount
+ if sink_account:
+ for currency, amount in debt.items():
+ apply_booking_to_account_balances(account_changes, sink_account, currency, -amount)
+ return account_changes
+
+
+
+class Database:
+
+ def __init__(self, load_from_file=True):
+ import os
+ db_name = "_ledger"
+ self.db_file = db_name + ".json"
+ self.lock_file = db_name+ ".lock"
+ self.bookings = []
+ self.comments = []
+ if load_from_file and os.path.exists(self.db_file):
+ with open(self.db_file, "r") as f:
+ self.parse_lines(f.readlines())
+
+ def parse_lines(self, lines):
+ import datetime
+ import decimal
+ inside_booking = False
+ date_string, description = None, None
+ booking_lines = []
+ start_line = 0
+ for i, line in enumerate(lines):
+ prefix = f"line {i}"
+ # we start with the case of an utterly empty line
+ self.comments += [""]
+ stripped_line = line.rstrip()
+ if stripped_line == '':
+ if inside_booking:
+ # assume we finished a booking, finalize, and commit to DB
+ if len(booking_lines) < 2:
+ raise HandledException(f"{prefix} booking ends to early")
+ booking = Booking(date_string, description, booking_lines, start_line)
+ self.bookings += [booking]
+ # expect new booking to follow so re-zeroall booking data
+ inside_booking = False
+ date_string, description = None, None
+ booking_lines = []
+ continue
+ # if non-empty line, first get comment if any, and commit to DB
+ split_by_comment = stripped_line.split(sep=";", maxsplit=1)
+ if len(split_by_comment) == 2:
+ self.comments[i] = split_by_comment[1]
+ # if pre-comment empty: if inside_booking, this must be a comment-only line so we keep it for later ledger-output to capture those comments; otherwise, no more to process for this line
+ non_comment = split_by_comment[0].rstrip()
+ if non_comment.rstrip() == '':
+ if inside_booking:
+ booking_lines += ['']
+ continue
+ # if we're starting a booking, parse by first-line pattern
+ if not inside_booking:
+ start_line = i
+ toks = non_comment.split(maxsplit=1)
+ date_string = toks[0]
+ try:
+ datetime.datetime.strptime(date_string, '%Y-%m-%d')
+ except ValueError:
+ raise HandledException(f"{prefix} bad date string: {date_string}")
+ try:
+ description = toks[1]
+ except IndexError:
+ raise HandledException(f"{prefix} bad description: {description}")
+ inside_booking = True
+ continue
+ # otherwise, read as transfer data
+ toks = non_comment.split() # ignore specification's allowance of single spaces in names
+ if len(toks) > 3:
+ raise HandledException(f"{prefix} too many booking line tokens: {toks}")
+ amount, currency = None, None
+ account_name = toks[0]
+ if account_name[0] == '[' and account_name[-1] == ']':
+ # ignore specification's differentiation of "virtual" accounts
+ account_name = account_name[1:-1]
+ decimal_chars = ".-0123456789"
+ if len(toks) == 3:
+ i_currency = 1
+ try:
+ amount = decimal.Decimal(toks[1])
+ i_currency = 2
+ except decimal.InvalidOperation:
+ try:
+ amount = decimal.Decimal(toks[2])
+ except decimal.InvalidOperation:
+ raise HandledException(f"{prefix} no decimal number in: {toks[1:]}")
+ currency = toks[i_currency]
+ if currency[0] in decimal_chars:
+ raise HandledException(f"{prefix} currency starts with int, dot, or minus: {currency}")
+ elif len(toks) == 2:
+ value = toks[1]
+ inside_amount = False
+ inside_currency = False
+ amount_string = ""
+ currency = ""
+ dots_counted = 0
+ for i, c in enumerate(value):
+ if i == 0:
+ if c in decimal_chars:
+ inside_amount = True
+ else:
+ inside_currency = True
+ if inside_currency:
+ if c in decimal_chars and len(amount_string) == 0:
+ inside_currency = False
+ inside_amount = True
+ else:
+ currency += c
+ continue
+ if inside_amount:
+ if c not in decimal_chars:
+ if len(currency) > 0:
+ raise HandledException(f"{prefix} amount has non-decimal chars: {value}")
+ inside_currency = True
+ inside_amount = False
+ currency += c
+ continue
+ if c == '-' and len(amount_string) > 1:
+ raise HandledException(f"{prefix} amount has non-start '-': {value}")
+ if c == '.':
+ if dots_counted > 1:
+ raise HandledException(f"{prefix} amount has multiple dots: {value}")
+ dots_counted += 1
+ amount_string += c
+ if len(amount_string) == 0:
+ raise HandledException(f"{prefix} amount missing: {value}")
+ if len(currency) == 0:
+ raise HandledException(f"{prefix} currency missing: {value}")
+ amount = decimal.Decimal(amount_string)
+ booking_lines += [(account_name, amount, currency)]
+
+ def ledger_as_html(self):
+ lines = []
+ for comment in self.comments:
+ lines += [f"; {comment}" if comment != '' else '']
+ for booking in self.bookings:
+ i = booking.start_line
+ suffix = f" {lines[i]}" if len(lines[i]) > 0 else ""
+ lines[i] = f"{booking.date_string} {booking.description}{suffix}"
+ for booking_line in booking.lines:
+ i += 1
+ if booking_line == '':
+ continue
+ suffix = f" {lines[i]}" if len(lines[i]) > 0 else ""
+ value = f" {booking_line[1]} {booking_line[2]}" if booking_line[1] else ""
+ lines[i] = f"{booking_line[0]}{value}{suffix}"
+ content = "\n".join(lines)
+ return f"<html><meta charset=\"UTF-8\"><pre>{content}</pre></html>"
+
+ def balance_as_html(self):
+ account_sums = {}
+ for booking in self.bookings:
+ for account, changes in booking.account_changes.items():
+ for currency, amount in changes.items():
+ apply_booking_to_account_balances(account_sums, account, currency, amount)
+ account_tree = {}
+ def collect_branches(account_name, path):
+ node = account_tree
+ path_copy = path[:]
+ while len(path_copy) > 0:
+ step = path_copy.pop(0)
+ node = node[step]
+ toks = account_name.split(":", maxsplit=1)
+ parent = toks[0]
+ if parent in node.keys():
+ child = node[parent]
+ else:
+ child = {}
+ node[parent] = child
+ if len(toks) == 2:
+ k, v = collect_branches(toks[1], path + [parent])
+ if k not in child.keys():
+ child[k] = v
+ else:
+ child[k].update(v)
+ return parent, child
+ for account_name in sorted(account_sums.keys()):
+ k, v = collect_branches(account_name, [])
+ if k not in account_tree.keys():
+ account_tree[k] = v
+ else:
+ account_tree[k].update(v)
+ def collect_totals(parent_path, tree_node):
+ for k, v in tree_node.items():
+ child_path = parent_path + ":" + k
+ for currency, amount in collect_totals(child_path, v).items():
+ apply_booking_to_account_balances(account_sums, parent_path, currency, amount)
+ return account_sums[parent_path]
+ for account_name in account_tree.keys():
+ account_sums[account_name] = collect_totals(account_name, account_tree[account_name])
+ lines = []
+ def print_subtree(lines, indent, node, subtree, path):
+ line = f"{indent}{node}"
+ n_tabs = 5 - (len(line) // 8)
+ line += n_tabs * "\t"
+ if "€" in account_sums[path + node].keys():
+ amount = account_sums[path + node]["€"]
+ line += f"{amount:9.2f} €\t"
+ else:
+ line += f"\t\t"
+ for currency, amount in account_sums[path + node].items():
+ if currency != '€' and amount > 0:
+ line += f"{amount:5.2f} {currency}\t"
+ lines += [line]
+ indent += " "
+ for k, v in sorted(subtree.items()):
+ print_subtree(lines, indent, k, v, path + node + ":")
+ for k, v in sorted(account_tree.items()):
+ print_subtree(lines, "", k, v, "")
+ content = "\n".join(lines)
+ return f"<html><meta charset=\"UTF-8\"><pre>{content}</pre></html>"
+
+
+class MyServer(BaseHTTPRequestHandler):
+
+ def do_GET(self):
+ self.send_response(200)
+ self.send_header("Content-type", "text/html")
+ self.end_headers()
+ db = Database()
+ # page = db.ledger_as_html()
+ page = db.balance_as_html()
+ self.wfile.write(bytes(page, "utf-8"))
+
+
+db = Database()
+if __name__ == "__main__":
+ webServer = HTTPServer((hostName, serverPort), MyServer)
+ print(f"Server started http://{hostName}:{serverPort}")
+ try:
+ webServer.serve_forever()
+ except KeyboardInterrupt:
+ pass
+ webServer.server_close()
+ print("Server stopped.")
projects / misc / commitdiff