Use named constants instead of strings for enum-like OFX fields

This adds a python script to generate constants.go when `go generate` is
called, and updates the structs, tests, and command-line client to all
use the new named constants.

generate_constants.py

@@ -0,0 +1,155 @@
+#!/usr/bin/env python
+
+enums = {
+    # Bank/general
+    "AcctType": ["Checking", "Savings", "MoneyMrkt", "CreditLine", "CD"],
+    "TrnType": ["Credit", "Debit", "Int", "Div", "Fee", "SrvChg", "Dep", "ATM", "POS", "Xfer", "Check", "Payment", "Cash", "DirectDep", "DirectDebit", "RepeatPmt", "Hold", "Other"],
+    "ImageType": ["Statement", "Transaction", "Tax"],
+    "ImageRefType": ["Opaque", "URL", "FormURL"],
+    "CheckSup": ["FrontOnly", "BackOnly", "FrontAndBack"],
+    "CorrectAction": ["Delete", "Replace"],
+    "BalType": ["Dollar", "Percent", "Number"],
+
+    # InvStmt
+    "Inv401kSource": ["PreTax", "AfterTax", "Match", "ProfitSharing", "Rollover", "OtherVest", "OtherNonVest"],
+    "SubAcctType": ["Cash", "Margin", "Short", "Other"], # used in fields named: SubAcctSec, HeldInAcct, SubAcctFund
+    "BuyType": ["Buy", "BuyToCover"],
+    "OptAction": ["Exercise", "Assign", "Expire"],
+    "TferAction": ["In", "Out"],
+    "PosType": ["Long", "Short"],
+    "Secured": ["Naked", "Covered"],
+    "Duration": ["Day", "GoodTilCancel", "Immediate"],
+    "Restriction": ["AllOrNone", "MinUnits", "None"],
+    "UnitType": ["Shares", "Currency"],
+    "OptBuyType": ["BuyToOpen", "BuyToClose"],
+    "SellType": ["Sell", "SellShort"],
+    "LoanPmtFreq": ["Weekly", "Biweekly", "TwiceMonthly", "Monthly", "FourWeeks", "BiMonthly", "Quarterly", "Semiannually", "Annually", "Other"],
+    "IncomeType": ["CGLong", "CGShort", "Div", "Interest", "Misc"],
+    "SellReason": ["Call", "Sell", "Maturity"],
+    "OptSellType": ["SellToClose", "SellToOpen"],
+    "RelType": ["Spread", "Straddle", "None", "Other"],
+
+    # Prof
+    "CharType": ["AlphaOnly", "NumericOnly", "AlphaOrNumeric", "AlphaAndNumeric"],
+    "SyncMode": ["Full", "Lite"],
+
+    # SecList
+    "DebtType": ["Coupon", "Zero"],
+    "DebtClass": ["Treasury", "Municipal", "Corporate", "Other"],
+    "CouponFreq": ["Monthly", "Quarterly", "Semiannual", "Annual", "Other"],
+    "CallType": ["Call", "Put", "Prefund", "Maturity"],
+    "AssetClass": ["DomesticBond", "IntlBond", "LargeStock", "SmallStock", "IntlStock", "MoneyMrkt", "Other"],
+    "MfType": ["Open", "End", "CloseEnd", "Other"],
+    "OptType": ["Put", "Call"],
+    "StockType": ["Common", "Preferred", "Convertible", "Other"],
+    "OfxSec": ["None", "Type 1"],
+
+    # Signup
+    "HolderType": ["Individual", "Joint", "Custodial", "Trust", "Other"],
+    "AcctClassification": ["Personal", "Business", "Corporate", "Other"],
+    "SvcStatus": ["Avail", "Pend", "Active"],
+    "UsProductType": ["401K", "403B", "IRA", "KEOGH", "Other", "SARSEP", "Simple", "Normal", "TDA", "Trust", "UGMA"],
+}
+
+header = """package ofxgo
+
+/*
+ * Do not edit this file by hand. It is auto-generated by calling `go generate`.
+ * To make changes, edit generate_constants.py, re-run `go generate`, and check
+ * in the result.
+ */
+
+import (
+	"errors"
+	"fmt"
+	"github.com/aclindsa/go/src/encoding/xml"
+	"strings"
+)
+"""
+
+template = """
+type {enumLower} uint
+
+const (
+{constNames})
+
+var {enumLower}s = [...]string{{"{upperValueString}"}}
+
+func (e {enumLower}) Valid() bool {{
+	return e >= {firstValue} && e <= {lastValue}
+}}
+
+func (e {enumLower}) String() string {{
+	if e.Valid() {{
+		return {enumLower}s[e-1]
+	}}
+	return fmt.Sprintf("invalid {enumLower} (%d)", e)
+}}
+
+func (e *{enumLower}) FromString(in string) error {{
+	value := strings.TrimSpace(in)
+
+	for i, s := range {enumLower}s {{
+		if s == value {{
+			*e = {enumLower}(i + 1)
+			return nil
+		}}
+	}}
+	return errors.New("Invalid {enum}: \\\"" + in + "\\\"")
+}}
+
+func (e *{enumLower}) UnmarshalXML(d *xml.Decoder, start xml.StartElement) error {{
+	var value string
+	err := d.DecodeElement(&value, &start)
+	if err != nil {{
+		return err
+	}}
+
+	return e.FromString(value)
+}}
+
+func (e *{enumLower}) MarshalXML(enc *xml.Encoder, start xml.StartElement) error {{
+	if *e == 0 {{
+		return nil
+	}} else if !e.Valid() {{
+		return errors.New("Invalid {enum}")
+	}}
+	enc.EncodeElement({enumLower}s[*e-1], start)
+	return nil
+}}
+
+func New{enum}(s string) ({enumLower}, error) {{
+	var e {enumLower}
+	err := e.FromString(s)
+	if err != nil {{
+		return 0, err
+	}}
+	return e, nil
+}}
+"""
+
+with open("constants.go", 'w') as f:
+    f.write(header)
+
+    for enum in enums:
+        enumLower = enum[:1].lower() + enum[1:].replace(" ", "")
+        firstValue = enum+enums[enum][0].replace(" ", "")
+        lastValue = enum+enums[enum][-1].replace(" ", "")
+
+        constNames = "\t{firstValue} {enumLower} = 1 + iota\n".format(
+            enum=enum,
+            firstValue=firstValue,
+            enumLower=enumLower)
+        for value in enums[enum][1:]:
+            constNames += "\t{enum}{value}\n".format(
+                enum=enum,
+                value=value.replace(" ", ""))
+
+        upperValueString = "\", \"".join([s.upper() for s in enums[enum]])
+
+        f.write(template.format(enum=enum,
+                              enumLower=enumLower,
+                              firstValue=firstValue,
+                              lastValue=lastValue,
+                              constNames=constNames,
+                              upperValueString=upperValueString))