From 25c6454e2d968f4a8e5076d87a859e0782549efa Mon Sep 17 00:00:00 2001
From: Brett Smith <brettcsmith@brettcsmith.org>
Date: Wed, 27 Dec 2017 13:44:35 -0500
Subject: [PATCH] importers.amazon: Initial version.

---
 import2ledger/importers/amazon.py | 66 +++++++++++++++++++++++++++++++
 1 file changed, 66 insertions(+)
 create mode 100644 import2ledger/importers/amazon.py

diff --git a/import2ledger/importers/amazon.py b/import2ledger/importers/amazon.py
new file mode 100644
index 0000000..6927e97
--- /dev/null
+++ b/import2ledger/importers/amazon.py
@@ -0,0 +1,66 @@
+import datetime
+import itertools
+
+from . import _csv
+from .. import strparse
+
+class NewMonthEarnings(Exception):
+    pass
+
+
+class MonthlyEarnings:
+    def __init__(self):
+        self.dates = []
+        self.amounts = []
+
+    def in_same_month(self, date):
+        try:
+            start_date = self.dates[0]
+        except IndexError:
+            return True
+        else:
+            return start_date.year == date.year and start_date.month == date.month
+
+    def add(self, row):
+        date = strparse.date(strparse.slice_words(row['Date Shipped'], 0), '%Y-%m-%d')
+        amount = strparse.currency_decimal(row['Ad Fees($)'])
+        if self.in_same_month(date):
+            self.dates.append(date)
+            self.amounts.append(amount)
+        else:
+            raise NewMonthEarnings()
+
+    def report(self):
+        return {
+            'amount': sum(self.amounts),
+            'date': max(self.dates),
+        }
+
+
+class EarningsImporter(_csv.CSVImporterBase):
+    SENTINEL_ROW = {
+        'Ad Fees($)': '0',
+        'Date Shipped': '1979-07-09',
+    }
+    NEEDED_FIELDS = frozenset(SENTINEL_ROW.keys())
+    TEMPLATE_KEY = 'template amazon earnings'
+    ENTRY_SEED = {
+        'currency': 'USD',
+        'payee': 'Amazon',
+    }
+
+    def __init__(self, input_file):
+        super().__init__(input_file)
+        self.in_csv = itertools.chain(self.in_csv, [self.SENTINEL_ROW])
+        self.earnings = MonthlyEarnings()
+
+    def _read_row(self, row):
+        try:
+            self.earnings.add(row)
+        except NewMonthEarnings:
+            retval = self.earnings.report()
+            self.earnings = MonthlyEarnings()
+            self.earnings.add(row)
+        else:
+            retval = None
+        return retval