Move cum-calcs to `open_ledger_dfs()`, always parse `str`->`Datetime`

Previously the cum-size calc(s) was in the `disect` CLI but it's better
stuffed into the backing df converter. Also, ensure that whenever
a `dt` field is type-detected as a `str` we parse it to `DateTime`.

piker/accounting/calc.py

@@ -20,6 +20,7 @@ you know when you're losing money (if possible) XD
 
 '''
 from __future__ import annotations
+from collections.abc import ValuesView
 from contextlib import contextmanager as cm
 from math import copysign
 from typing import (
@@ -39,6 +40,7 @@ from pendulum import (
 if TYPE_CHECKING:
     from ._ledger import (
         Transaction,
+        TransactionLedger,
     )
 
 def ppu(
@@ -72,18 +74,23 @@ def ppu(
     where `cost_basis` for the current step is simply the price
     * size of the most recent clearing transaction.
 
+    -----
+    TODO: get the BEP computed and working similarly!
+    -----
+    the equivalent "break even price" or bep at each new clear
+    event step conversely only changes when an "position exiting
+    clear" which **decreases** the cumulative dst asset size:
+
+    bep[-1] = ppu[-1] - (cum_pnl[-1] / cumsize[-1])
+
     '''
     asize_h: list[float] = []  # historical accumulative size
     ppu_h: list[float] = []  # historical price-per-unit
     ledger: dict[str, dict] = {}
 
-    # entry: dict[str, Any] | Transaction
     t: Transaction
     for t in clears:
-        # tid: str = entry['tid']
-        # clear_size = entry['size']
         clear_size: float = t.size
-        # clear_price: str | float = entry['price']
         clear_price: str | float = t.price
         is_clear: bool = not isinstance(clear_price, str)
 
@@ -152,7 +159,6 @@ def ppu(
                 clear_price * abs(clear_size)
                 +
                 # transaction cost
-                # accum_sign * cost_scalar * entry['cost']
                 accum_sign * cost_scalar * t.cost
             )
 
@@ -187,13 +193,13 @@ def ppu(
         asize_h.append(accum_size)
 
         # ledger[t.tid] = {
-            # 'tx': t,
+            # 'txn': t,
         ledger[t.tid] = t.to_dict() | {
             'ppu': ppu,
             'cumsize': accum_size,
             'sign_change': sign_change,
 
-            # TODO: cumpnl, bep
+            # TODO: cum_pnl, bep
         }
 
     final_ppu = ppu_h[-1] if ppu_h else 0
@@ -212,6 +218,7 @@ def ppu(
 def iter_by_dt(
     records: (
         dict[str, dict[str, Any]]
+        | ValuesView[dict]  # eg. `Position._events.values()`
         | list[dict]
         | list[Transaction]  # XXX preferred!
     ),
@@ -220,7 +227,7 @@ def iter_by_dt(
     # so if you know that the record stats show some field
     # is more common then others, stick it at the top B)
     parsers: dict[str, Callable | None] = {
-        'dt': None,  # parity case
+        'dt': parse,  # parity case
         'datetime': parse,  # datetime-str
         'time': from_timestamp,  # float epoch
     },
@@ -259,8 +266,13 @@ def iter_by_dt(
                 # the `parsers` table above (when NOT using
                 # `.get()`), otherwise pass through the value and
                 # sort on it directly
-                parser: Callable | None = parsers[k]
+                if (
-                return parser(v) if (parser is not None) else v
+                    not isinstance(v, DateTime)
+                    and (parser := parsers.get(k))
+                ):
+                    return parser(v)
+                else:
+                    return v
 
         else:
             # XXX: should never get here..
@@ -271,6 +283,7 @@ def iter_by_dt(
         records,
         key=key or dyn_parse_to_dt,
     ):
+        # NOTE the type sig above; either pairs or txns B)
         yield entry
 
 
@@ -331,7 +344,14 @@ def open_ledger_dfs(
     brokername: str,
     acctname: str,
 
-) -> dict[str, pl.DataFrame]:
+    ledger: TransactionLedger | None = None,
+
+    **kwargs,
+
+) -> tuple[
+    dict[str, pl.DataFrame],
+    TransactionLedger,
+]:
     '''
     Open a ledger of trade records (presumably from some broker
     backend), normalize the records into `Transactions` via the
@@ -341,25 +361,32 @@ def open_ledger_dfs(
     '''
     from ._ledger import (
         open_trade_ledger,
-        # Transaction,
-        TransactionLedger,
     )
 
-    ledger: TransactionLedger
+    if not ledger:
         import time
+        from tractor._debug import open_crash_handler
         now = time.time()
+
         with (
+            open_crash_handler(),
+
             open_trade_ledger(
                 brokername,
                 acctname,
                 rewrite=True,
                 allow_from_sync_code=True,
+
+                # proxied through from caller
+                **kwargs,
+
             ) as ledger,
         ):
             if not ledger:
                 raise ValueError(f'No ledger for {acctname}@{brokername} exists?')
 
             print(f'LEDGER LOAD TIME: {time.time() - now}')
+
             # process raw TOML ledger into txns using the
             # appropriate backend normalizer.
             # cache: AssetsInfo = get_symcache(
@@ -367,12 +394,7 @@ def open_ledger_dfs(
             #     allow_reload=True,
             # )
 
-        txns: dict[str, Transaction]
+    txns: dict[str, Transaction] = ledger.to_txns()
-        if acctname != 'paper':
-            txns = ledger.mod.norm_trade_records(ledger)
-        else:
-            txns = ledger.to_txns()
-
     ldf = pl.DataFrame(
         list(txn.to_dict() for txn in txns.values()),
         # schema=[
@@ -385,13 +407,14 @@ def open_ledger_dfs(
         #     ('expiry', str),
         #     ('bs_mktid', str),
         # ],
-        ).sort('dt').select([
+    # ).sort('dt').select([
-            pl.col('fqme'),
+    ).sort('dt').with_columns([
+        # pl.col('fqme'),
         pl.col('dt').str.to_datetime(),
         # pl.col('expiry').dt.datetime(),
-            pl.col('bs_mktid'),
+        # pl.col('bs_mktid'),
-            pl.col('size'),
+        # pl.col('size'),
-            pl.col('price'),
+        # pl.col('price'),
     ])
 
     # filter out to the columns matching values filter passed
@@ -408,19 +431,19 @@ def open_ledger_dfs(
         # bs_mktid: str = fdf[0]['bs_mktid']
         # pos: Position = acnt.pps[bs_mktid]
 
+    # TODO: not sure if this is even possible but..
     # ppt = df.groupby('fqme').agg([
     #     # TODO: ppu and bep !!
     #     pl.cumsum('size').alias('cumsum'),
     # ])
-
     dfs: dict[str, pl.DataFrame] = ldf.partition_by(
         'fqme',
         as_dict=True,
     )
+    for key in dfs:
+        df = dfs[key]
+        dfs[key] = df.with_columns([
+            pl.cumsum('size').alias('cumsize'),
+        ])
 
-        # for fqme, ppt in act.items():
+    yield dfs, ledger
-        #     ppt.with_columns
-        #     # TODO: ppu and bep !!
-        #     pl.cumsum('size').alias('cumsum'),
-        # ])
-        yield dfs

piker/accounting/cli.py

@@ -37,8 +37,8 @@ from ..calc import humanize
 from ..brokers._daemon import broker_init
 from ._ledger import (
     load_ledger,
+    TransactionLedger,
     # open_trade_ledger,
-    # TransactionLedger,
 )
 from .calc import (
     open_ledger_dfs,
@@ -263,20 +263,17 @@ def disect(
 
     # ledger dfs groupby-partitioned by fqme
     dfs: dict[str, pl.DataFrame]
+    # actual ledger ref filled in with all txns
+    ldgr: TransactionLedger
+
     with open_ledger_dfs(
         brokername,
         account,
-    ) as dfs:
+    ) as (dfs, ldgr):
 
-        for key in dfs:
+        # look up specific frame for fqme-selected asset
-            df = dfs[key]
+        df = dfs[fqme]
-            dfs[key] = df.with_columns([
-                pl.cumsum('size').alias('cumsum'),
-            ])
-
-        ppt = dfs[fqme]
         assert not df.is_empty()
-        assert not ppt.is_empty()
 
         # TODO: we REALLY need a better console REPL for this
         # kinda thing..