From 610862b3a703790e6a5546b97fdb3b11efe09233 Mon Sep 17 00:00:00 2001
From: "Timur A. Fatkhullin" <amirych@gmail.com>
Date: Sat, 8 Mar 2025 10:50:18 +0300
Subject: [PATCH] ...

---
 cxx/mount_astrom.h | 60 ++++++++++++++++++++++++++++++++++++++++++++--
 1 file changed, 58 insertions(+), 2 deletions(-)

diff --git a/cxx/mount_astrom.h b/cxx/mount_astrom.h
index 497e130..67bc35a 100644
--- a/cxx/mount_astrom.h
+++ b/cxx/mount_astrom.h
@@ -185,7 +185,11 @@ struct earth_orient_db_elem_t {
 };
 
 
-typedef std::vector<earth_orient_db_elem_t> earth_orient_db_t;
+// typedef std::vector<earth_orient_db_elem_t> earth_orient_db_t;
+struct earth_orient_db_t {
+    std::chrono::system_clock::time_point bulletinDate{};
+    std::vector<earth_orient_db_elem_t> db{};
+};
 
 // init to some known state
 static leapsecond_db_t CURRENT_LEAPSECONDS_DB = {
@@ -202,8 +206,30 @@ static leapsecond_db_t CURRENT_LEAPSECONDS_DB = {
 
 };
 
+
+static earth_orient_db_t CURRENT_EARTH_ORIENT_DB;
+
 bool mcc_parse_bulletinA(std::derived_from<std::basic_istream<char>> auto& stream, char comment_sym = '*')
 {
+    const std::regex bull_date_rx{
+        "^ *[0-9]{1,2} +(January|Febraury|March|April|May|June|July|August|September|October|November|December) "
+        "+[0-9]{4,} + Vol\\.[XMLCDVI]+ +No\\. +[0-9]+ *$"};
+
+    const std::regex bull_tab_title_rx{"^ *MJD +x\\(arcsec\\) +y\\(arcsec\\) +UT1-UTC\\(sec\\) *$"};
+
+    // 2025  3  7  60741       0.0663      0.3341      0.04348
+    const std::regex bull_tab_vals_rx{
+        "^ *[0-9]{4,} +[0-9]{1,2} +[0-9]{1,2} +[0-9]{5,} +[0-9]+\\.[0-9]+ +[0-9]+\\.[0-9]+ +[0-9]+\\.[0-9]+ *$"};
+
+    earth_orient_db_t db;
+    enum { TAB_STATE_SEEK, TAB_STATE_START };
+    int tab_state = TAB_STATE_SEEK;
+
+    int year;
+    unsigned month, day;
+    double mjd, x, y, dut1;
+    std::istringstream is;
+
     for (std::string line; std::getline(stream, line);) {
         if (line.empty()) {
             continue;
@@ -215,11 +241,41 @@ bool mcc_parse_bulletinA(std::derived_from<std::basic_istream<char>> auto& strea
             if (sv[0] == comment_sym) {  // comment string
                 continue;
             }
-        } else {
+
+            if (tab_state == TAB_STATE_START) {
+                if (std::regex_match(sv.begin(), sv.end(), bull_tab_vals_rx)) {
+                    is.str({sv.begin(), sv.end()});
+                    is >> year >> month >> day >> mjd >> x >> y >> dut1;
+                    db.db.emplace_back(year, month, day, mjd, x, y, dut1);
+                } else {  // end of the table - just stop parsing
+                    break;
+                }
+
+                continue;
+            }
+
+            if (std::regex_match(sv.begin(), sv.end(), bull_date_rx)) {
+                is.str({sv.begin(), sv.end()});
+                is >> std::chrono::parse("%d %B %Y", db.bulletinDate);
+                continue;
+            }
+
+            if (std::regex_match(sv.begin(), sv.end(), bull_tab_title_rx)) {
+                tab_state = TAB_STATE_START;
+                continue;
+            }
+
+        } else {  // empty string (only spaces)
             continue;
         }
     }
 
+    if (db.db.empty()) {
+        return false;
+    }
+
+    CURRENT_EARTH_ORIENT_DB = std::move(db);
+
     return true;
 }