#!/usr/bin/env python3
"""Local web front end for the statement loader.  Run:  .venv/bin/python app.py
Opens http://127.0.0.1:8765  - listens on this Mac only; nothing is sent anywhere.
"""
import os, json, secrets, shutil, subprocess, sys, re, calendar, datetime as dt, threading, webbrowser
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
from pathlib import Path
from urllib.parse import urlparse, parse_qs
import statement_loader as L
import budget as B

PORT = int(os.environ.get("PORT", "8765"))
BIND = os.environ.get("BIND", "127.0.0.1")   # in Docker: 0.0.0.0 (publish the port to 127.0.0.1 only)
EXTRA_HOSTS = {h.strip() for h in os.environ.get("ALLOWED_HOSTS", "").split(",") if h.strip()}
TOKEN = secrets.token_urlsafe(24)
LOCK = threading.Lock()
HERE = L.HERE      # code and pages
DATA = L.DATA      # statements and workbook

def eom(y, m): return calendar.monthrange(y, m)[1]

def coverage(sts):
    today = dt.date.today()
    cfg = {a[0]: a[2] for a in L.ACCOUNTS}
    by = {}
    recent = {}                      # "Account Details" pages: partial months, never count as a full statement
    for st in sts:
        if st.kind == "activity": recent[st.account] = max(recent.get(st.account, st.end), st.end)
        else: by.setdefault(st.account, []).append(st)
    if not by: return dict(months=[], accounts=[])
    lo = min(s.start or s.end for s in sum(by.values(), [])); months = []
    y, m = lo.year, lo.month
    while (y, m) <= (today.year, today.month):
        months.append(f"{y}-{m:02d}"); m += 1
        if m > 12: y, m = y + 1, 1
    out = []
    for acct, lst in by.items():
        csv_only = all(s.kind == "csv" for s in lst)
        ends = {s.end.day for s in lst}; day = cfg.get(acct) or (ends.pop() if len(ends) == 1 and max(ends) < 28 else None)   # accounts not in ACCOUNTS: reuse their usual closing day
        cells, first = {}, min((s.start or s.end) for s in lst)
        for mo in months:
            y, m = int(mo[:4]), int(mo[5:])
            if csv_only:
                have = any((s.start.year, s.start.month) <= (y, m) <= (s.end.year, s.end.month) for s in lst)
                cells[mo] = "have" if have else ("future" if (y, m) > (max(s.end for s in lst).year, max(s.end for s in lst).month) else ("none" if (y, m) < (first.year, first.month) else "missing"))
                continue
            have = any((s.end.year, s.end.month) == (y, m) for s in lst)
            due = dt.date(y, m, day or eom(y, m))
            started = (y, m) >= (min(s.end for s in lst).year, min(s.end for s in lst).month)
            cells[mo] = "have" if have else ("none" if not started else ("future" if due > today else "missing"))
        last = max(s.end for s in lst)
        if csv_only:
            nxt = f"Next download: from {last + dt.timedelta(days=1):%b %-d, %Y}"
        else:
            ny, nm = (last.year, last.month + 1) if last.month < 12 else (last.year + 1, 1)
            if day is None and last.day != eom(last.year, last.month): ny, nm = last.year, last.month
            nd = dt.date(ny, nm, day or eom(ny, nm))
            nxt = f"Next statement closes ~{nd:%b %-d, %Y}" + (" (ready to download)" if nd <= today else "")
        if acct in recent and recent[acct] > last: nxt += f" · recent activity loaded through {recent[acct]:%b %-d}"
        out.append(dict(account=acct, cells=cells, count=len(lst), through=f"{last:%b %-d, %Y}", next=nxt, kind="csv" if csv_only else "pdf"))
    return dict(months=months, accounts=out)

def state():
    if not L.WORKBOOK.exists():
        return dict(setup=True, data_dir=str(DATA), rules=(DATA / "loader_rules.json").exists(),
                    files=sorted(p.name for p in DATA.glob("*") if p.is_file())[:50])
    res = L.run_preview(DATA)
    new = res["new"]
    rows = [dict(date=f"{r.txn.date:%Y-%m-%d}", account=r.txn.account, desc=r.txn.desc[:60], amount=r.txn.amount, kind=r.kind,
                 payee=r.payee, what=r.what, reason=r.reason, new_payee=r.is_new_payee) for r in new]
    sm = L.summarize(new)
    return dict(coverage=coverage(res["statements"] + L.archived_statements()), skipped=[dict(file=f, why=w) for f, w in res["skipped"]],
                duplicates=[dict(file=a, same_as=b) for a, b in res["dups"]],
                bad=[dict(file=f, parsed=p, stated=s) for f, p, s, ok in res["checks"] if not ok],
                already=res["already"], new=rows, accounts_new=len(res["snaps"]), archivable=(0 if (new or res["snaps"]) else len([x for x in res["statements"] if x.file not in res["bad"]])), summary=sm, statements=len(res["statements"]),
                excel_open=(DATA / "~$Bills_Tracker.xlsx").exists() or (DATA / ".~lock.Bills_Tracker.xlsx#").exists(),
                backups=sorted(p.name for p in L.BACKUPS.glob("*.xlsx"))[-5:] if L.BACKUPS.exists() else [])

_DATA = {}
def workbook_data():
    """Read-only snapshot of the Bill Log for the web dashboard (computed from raw cells, not cached formulas)."""
    from openpyxl import load_workbook
    if not L.WORKBOOK.exists(): return dict(tx=[], income=[], budget=[], categories=[], excluded=0, updated="", setup=True, data_dir=str(DATA))
    key = L.WORKBOOK.stat().st_mtime_ns
    if _DATA.get("key") == key: return _DATA["val"]
    wb = load_workbook(L.WORKBOOK, read_only=True)
    pay = {}
    for r in wb["Lists"].iter_rows(min_row=4, max_row=153, max_col=3, values_only=True):
        if r[0]: pay[r[0]] = (r[1] or "Other / Unsorted", r[2] or "Spending")
    cats = [r[0] for r in wb["Lists"].iter_rows(min_row=4, max_row=40, min_col=5, max_col=5, values_only=True) if r[0] and not str(r[0]).startswith("Slots")]
    tx = []
    for r in wb["Bill Log"].iter_rows(min_row=6, max_col=9, values_only=True):
        if isinstance(r[0], dt.datetime) and r[1] and r[5] is not None:
            c, t = pay.get(r[1], ("Other / Unsorted", "Spending"))
            tx.append([f"{r[0]:%Y-%m-%d}", r[1], c, t, r[4] or "", round(float(r[5]), 2), r[6] or "", r[8] or ""])
    budget = []
    if "Budget" in wb.sheetnames:
        for r in wb["Budget"].iter_rows(min_row=2, max_col=3, values_only=True):
            if r[0] and r[1] and isinstance(r[2], (int, float)):
                budget.append([r[0] if isinstance(r[0], str) else f"{r[0]:%Y-%m}", r[1], float(r[2])])
    ex, income = 0, []
    for r in wb["Excluded Transfers"].iter_rows(min_row=5, max_col=7, values_only=True):
        if not isinstance(r[0], dt.datetime): continue
        ex += 1
        if r[5] == "Money in" and r[6] in ("Income (payroll deposit)", "Interest earned"):
            m = re.search(r"EFT (.+?)\s*[;,]", r[2] or "")
            src = (m.group(1).strip().title() if m else (r[2] or "Other").title()) if r[6].startswith("Income") else "Interest"
            income.append([f"{r[0]:%Y-%m-%d}", src, "Interest" if r[6].startswith("Interest") else "Paycheck", round(float(r[4]), 2), r[1] or ""])
    wb.close()
    _DATA["key"], _DATA["val"] = key, dict(tx=tx, income=income, budget=budget, categories=cats, excluded=ex, updated=f"{dt.datetime.fromtimestamp(L.WORKBOOK.stat().st_mtime):%b %-d, %Y %-I:%M %p}")
    return _DATA["val"]

def safe_name(name):
    name = re.sub(r"[^\w.\- ]", "_", Path(name).name)
    if name == "Bills_Tracker.xlsx":
        if L.WORKBOOK.exists(): raise ValueError("Bills_Tracker.xlsx already exists in the data folder; it won't be overwritten.")
        return L.WORKBOOK
    if name == "loader_rules.json": return DATA / name
    if Path(name).suffix.lower() not in (".pdf", ".csv"): raise ValueError("Only PDF or CSV statements, Bills_Tracker.xlsx (first time only) or loader_rules.json can be added.")
    p = DATA / name; i = 1
    while p.exists():
        p = DATA / f"{Path(name).stem}_{i}{Path(name).suffix}"; i += 1
    return p

class H(BaseHTTPRequestHandler):
    def log_message(self, *a): pass
    def _send(self, code, body, ctype="application/json"):
        b = body if isinstance(body, bytes) else json.dumps(body).encode()
        self.send_response(code); self.send_header("Content-Type", ctype); self.send_header("Content-Length", str(len(b)))
        self.send_header("Cache-Control", "no-store"); self.end_headers(); self.wfile.write(b)
    def _ok_host(self):
        if "*" in EXTRA_HOSTS: return True   # LAN/NAS use: any hostname or IP (the app has no login, so keep it on a trusted network)
        h = self.headers.get("Host", ""); return h.rsplit(":", 1)[0] in {"127.0.0.1", "localhost"} | EXTRA_HOSTS or h in EXTRA_HOSTS
    def do_GET(self):
        if not self._ok_host(): return self._send(403, {"error": "forbidden"})
        u = urlparse(self.path)
        if u.path == "/": return self._send(200, PAGE.replace("__TOKEN__", TOKEN).encode(), "text/html; charset=utf-8")
        if u.path == "/dashboard":
            f = HERE / "app_dashboard.html"
            return self._send(200, f.read_bytes() if f.exists() else b"app_dashboard.html missing", "text/html; charset=utf-8")
        if u.path == "/api/data":
            with LOCK:
                try: return self._send(200, workbook_data())
                except Exception as e: return self._send(500, {"error": str(e)})
        if u.path == "/budget":
            f = HERE / "app_budget.html"
            return self._send(200, f.read_bytes().replace(b"__TOKEN__", TOKEN.encode()) if f.exists() else b"app_budget.html missing", "text/html; charset=utf-8")
        if u.path == "/api/budget":
            month = parse_qs(u.query).get("month", [B.this_month()])[0]
            with LOCK:
                try:
                    if not L.WORKBOOK.exists(): return self._send(200, {"setup": True})
                    return self._send(200, B.compute(workbook_data(), month))
                except Exception as e: return self._send(500, {"error": str(e)})
        if u.path == "/accounts":
            f = HERE / "app_accounts.html"
            return self._send(200, f.read_bytes().replace(b"__TOKEN__", TOKEN.encode()) if f.exists() else b"app_accounts.html missing", "text/html; charset=utf-8")
        if u.path == "/api/accounts":
            with LOCK:
                try:
                    if not L.WORKBOOK.exists(): return self._send(200, {"setup": True, "rows": []})
                    from openpyxl import load_workbook
                    wb = load_workbook(L.WORKBOOK, read_only=True, data_only=True)
                    try: rows = L.account_rows(wb)
                    finally: wb.close()
                    for r in rows:
                        for k in ("date", "due"): r[k] = r[k].isoformat() if r[k] else None
                    return self._send(200, {"rows": rows})
                except Exception as e: return self._send(500, {"error": str(e)})
        if u.path == "/api/budget_history":
            with LOCK:
                try:
                    if not L.WORKBOOK.exists(): return self._send(200, dict(months=[], envelopes=[]))
                    return self._send(200, B.history(workbook_data()))
                except Exception as e: return self._send(500, {"error": str(e)})
        if u.path == "/api/payees":
            with LOCK:
                try: return self._send(200, L.uncategorized())
                except Exception as e: return self._send(500, {"error": str(e)})
        if u.path == "/api/state":
            with LOCK:
                try: return self._send(200, state())
                except Exception as e: return self._send(500, {"error": str(e)})
        self._send(404, {"error": "not found"})
    def do_POST(self):
        if not self._ok_host() or self.headers.get("X-Token") != TOKEN: return self._send(403, {"error": "forbidden"})
        u = urlparse(self.path); n = int(self.headers.get("Content-Length") or 0)
        try:
            if u.path == "/api/upload":
                name = parse_qs(u.query).get("name", [""])[0]; data = self.rfile.read(n)
                with LOCK:
                    p = safe_name(name)
                    if p.name == "loader_rules.json": json.loads(data)   # must be valid JSON
                    DATA.mkdir(parents=True, exist_ok=True); p.write_bytes(data)
                return self._send(200, {"saved": p.name})
            body = self.rfile.read(n)
            if u.path == "/api/budget":
                req = json.loads(body or b"{}")
                with LOCK: out = L.set_budget(req["month"], req["budgets"])
                return self._send(200, {"message": f"Saved the {req['month']} budget ({out['rows']} envelopes). Backup: {out['backup']}."})
            if u.path == "/api/add_category":
                try:
                    with LOCK: out = L.add_category(json.loads(body or b"{}").get("name"))
                except ValueError as e: return self._send(400, {"error": str(e)})
                note = " It will show on the web pages; the Excel summary tabs only have 20 category slots." if out["beyond_excel"] else ""
                return self._send(200, {"message": f"Added category '{out['name']}'.{note} Backup: {out['backup']}.", "name": out["name"]})
            if u.path == "/api/set_categories":
                with LOCK: out = L.set_categories(json.loads(body or b"[]"))
                return self._send(200, {"message": f"Updated {out['updated']} payee(s). Backup: {out['backup']}."})
            if u.path == "/api/autocategorize":
                with LOCK: out = L.autocategorize()
                return self._send(200, {"message": f"Auto-categorized {out['updated']} payee(s); {out['remaining']} still need you. Backup: {out['backup']}."})
            if u.path == "/api/import":
                with LOCK:
                    res = L.run_preview(DATA)
                    if not res["new"] and not res["snaps"]: return self._send(200, {"message": "Nothing new to import."})
                    out = L.apply(res["new"], snaps=res["snaps"])
                    try: filed = L.archive_statements()["moved"]
                    except Exception: filed = 0
                tail = f" Filed {filed} statement(s) into Statements/year/month." if filed else ""
                acc = f" Recorded {out['accounts']} savings/loan balance(s) on the Accounts tab." if out["accounts"] else ""
                return self._send(200, {"message": f"Added {out['log_rows']} rows to the Bill Log and {out['excluded_rows']} to Excluded Transfers.{acc}{tail}",
                                        "backup": Path(out["backup"]).name, "new_payees": out["new_payees"]})
            if u.path == "/api/archive":
                try:
                    with LOCK: out = L.archive_statements()
                except ValueError as e: return self._send(400, {"error": str(e)})
                return self._send(200, {"message": f"Filed {out['moved']} statement(s) into Statements/year/month. They won't be read again."})
            if u.path == "/api/undo":
                with LOCK:
                    b = sorted(L.BACKUPS.glob("*.xlsx")) if L.BACKUPS.exists() else []
                    if not b: return self._send(200, {"message": "No backups to restore."})
                    keep = L.BACKUPS / f"before_undo_{dt.datetime.now():%Y%m%d_%H%M%S}.xlsx"
                    shutil.copy2(L.WORKBOOK, keep); shutil.copy2(b[-1], L.WORKBOOK)
                    back = L.unarchive_last()
                return self._send(200, {"message": f"Restored the workbook from {b[-1].name}." + (f" Moved {back} statement(s) back to the data folder." if back else "")})
            if u.path == "/api/create_blank":
                tpl = HERE / "template" / "Bills_Tracker.template.xlsx"
                with LOCK:
                    if L.WORKBOOK.exists(): return self._send(400, {"error": "Bills_Tracker.xlsx already exists; it won't be overwritten."})
                    if not tpl.exists(): return self._send(400, {"error": "Template not found in the app."})
                    DATA.mkdir(parents=True, exist_ok=True); shutil.copy2(tpl, L.WORKBOOK)
                return self._send(200, {"message": "Created a blank Bills_Tracker.xlsx. Now drop your statements in."})
            if u.path == "/api/open":
                if sys.platform != "darwin": return self._send(200, {"message": "Open Bills_Tracker.xlsx from the data folder on the host."})
                subprocess.run(["open", str(L.WORKBOOK)], check=False)
                return self._send(200, {"message": "Opening the workbook…"})
        except Exception as e:
            return self._send(400, {"error": str(e)})
        self._send(404, {"error": "not found"})

PAGE = (HERE / "app_page.html").read_text() if (HERE / "app_page.html").exists() else "<h1>app_page.html missing</h1>"

if __name__ == "__main__":
    if not L.WORKBOOK.exists(): print(f"WARNING: {L.WORKBOOK} not found - put Bills_Tracker.xlsx in the data folder.")
    srv = ThreadingHTTPServer((BIND, PORT), H)
    url = f"http://127.0.0.1:{PORT}/"
    print(f"Statement loader running at {url}   (Ctrl+C to stop)")
    if "--no-browser" not in sys.argv and not os.environ.get("DATA_DIR"): threading.Timer(0.8, lambda: webbrowser.open(url)).start()
    try: srv.serve_forever()
    except KeyboardInterrupt: print("\nStopped.")