From 239ee2437c78ce48fbd957b11ba068b8cfb8a60f Mon Sep 17 00:00:00 2001
From: Victor Shyba <victor1984@riseup.net>
Date: Wed, 22 Apr 2020 03:27:10 -0300
Subject: [PATCH] estimate only whats not downloaded

---
 lbry/wallet/header.py             |  7 +++++--
 tests/unit/wallet/test_headers.py | 10 ++++++++++
 2 files changed, 15 insertions(+), 2 deletions(-)

diff --git a/lbry/wallet/header.py b/lbry/wallet/header.py
index de366d802..fc9018562 100644
--- a/lbry/wallet/header.py
+++ b/lbry/wallet/header.py
@@ -136,6 +136,9 @@ class Headers:
     def estimated_timestamp(self, height):
         if height <= 0:
             return
+        if self.has_header(height):
+            offset = height * self.header_size
+            return struct.unpack('<I', self.io.getbuffer()[offset + 100: offset + 104])[0]
         return int(self.first_block_timestamp + (height * self.timestamp_average_offset))
 
     def estimated_julian_day(self, height):
@@ -162,7 +165,7 @@ class Headers:
 
     async def ensure_chunk_at(self, height):
         async with self.check_chunk_lock:
-            if await self.has_header(height):
+            if self.has_header(height):
                 log.debug("has header %s", height)
                 return
             return await self.fetch_chunk(height)
@@ -186,7 +189,7 @@ class Headers:
             f"Checkpoint mismatch at height {start}. Expected {self.checkpoints[start]}, but got {chunk_hash} instead."
         )
 
-    async def has_header(self, height):
+    def has_header(self, height):
         normalized_height = (height // 1000) * 1000
         if normalized_height in self.checkpoints:
             return normalized_height not in self.known_missing_checkpointed_chunks
diff --git a/tests/unit/wallet/test_headers.py b/tests/unit/wallet/test_headers.py
index 1b0e7628b..578b85512 100644
--- a/tests/unit/wallet/test_headers.py
+++ b/tests/unit/wallet/test_headers.py
@@ -153,6 +153,16 @@ class TestHeaders(AsyncioTestCase):
         self.assertIsNone(headers.estimated_timestamp(0))
         self.assertIsNotNone(headers.estimated_timestamp(1))
 
+    async def test_dont_estimate_whats_there(self):
+        headers = Headers(':memory:')
+        await headers.open()
+        estimated = headers.estimated_timestamp(10)
+        await headers.connect(0, HEADERS)
+        real_time = (await headers.get(10))['timestamp']
+        after_downloading_header_estimated = headers.estimated_timestamp(10)
+        self.assertNotEqual(estimated, after_downloading_header_estimated)
+        self.assertEqual(after_downloading_header_estimated, real_time)
+
     async def test_misalignment_triggers_repair_on_open(self):
         headers = Headers(':memory:')
         headers.io.seek(0)