Update README.md

Author: formeo

README.md

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 # FirebirdRepairBase
-Program for analize and repare broken firebird database, it is working on the low level
-This is dirty version of program, now program is in develop process.
-
-Now it features: 
-* check database pages by type
-* replace some header page params
-* set READ ONLY and FORCE WRITE flags
-* replace check sum on pages
-* generate new page
-
-# In developing
-* Analisys pages, pump data.
-* Analisys TIP sequence, generate lost TIP pages
-
-# Firebird Database Pages
-* Database Header Page
-* Page Inventory Page (PIP)
-* Transaction Inventory Page (TIP)
-* Pointer Page
-* Data Page
-* Index Root Page
-* Index B-Tree Page
-* Blob Data Page
-* Generator Page
-* Write Ahead Log Page
+
+A low-level tool for analyzing and potentially recovering data from **broken** Firebird database files (`.fdb`, `.gdb`). It bypasses the standard Firebird engine to read raw page structures and data.
+
+**Warning:** This is a **development version**. It directly manipulates database files. Always create a **backup** of your database before using this tool. Use at your own risk.
+
+## Features
+
+*   **Database Structure Analysis:**
+    *   Opens and reads Firebird database files.
+    *   Identifies and counts pages by type (Header, PIP, TIP, Pointer, Data, Index Root/BTree, Blob, Generator, WAL).
+    *   Displays basic page information (number, type, checksum, relation ID).
+*   **Header Manipulation:**
+    *   Reads and interprets database header flags.
+    *   Allows setting/clearing specific flags (e.g., Read Only, Force Write).
+*   **Page Content Inspection:**
+    *   Reads specific pages by number.
+    *   Extracts and displays raw record fragments from Data Pages.
+    *   Allows changing page type and checksum (Dangerous!).
+*   **Transaction Analysis:**
+    *   Reads Transaction Inventory Pages (TIP).
+    *   Counts transactions by state (Active, Limbo, Dead, Committed).
+*   **Basic Data Recovery:**
+    *   Extracts raw data fragments from Data Pages.
+    *   *(WIP)* Basic MVCC (Multi-Version Concurrency Control) awareness for data visibility (see TODO).
+    *   *(New)* Parses basic record headers to identify deleted records and data length.
+*   **Record Fragment Parsing:**
+    *   Introduces `uRecordParser` module for analyzing individual record fragments.
+    *   Extracts key information like transaction ID, back pointer, flags, and data length from the record header.
+
+## In Development (TODO)
+
+*   **Advanced Data Recovery:**
+    *   Implement full MVCC logic to reconstruct the correct, visible version of records based on transaction states and TIP page data.
+    *   Export recovered data to a new, valid Firebird database or other formats (e.g., CSV).
+    *   Analyze and potentially repair B-Tree index structures.
+    *   Analyze and potentially repair Blob page chains.
+*   **Deeper Integrity Checks:**
+    *   Verify logical links between pages (e.g., Pointer Pages -> Data Pages, Record Back Pointers).
+    *   Identify orphaned pages.
+*   **Page Generation/Repair:**
+    *   Implement logic to generate missing TIP or PIP pages if necessary.
+    *   Attempt to rebuild damaged page structures.
+*   **User Interface Improvements:**
+    *   Add search functionality within page data.
+    *   Provide more detailed views for different page types (B-Tree keys, Blob data).
+    *   Add a 'Restore from Backup' feature.
+    *   Improve error handling and user feedback.
+
+## Supported Firebird Pages
+
+*   Database Header Page
+*   Page Inventory Page (PIP)
+*   Transaction Inventory Page (TIP)
+*   Pointer Page
+*   Data Page
+*   Index Root Page
+*   Index B-Tree Page
+*   Blob Data Page
+*   Generator Page
+*   Write Ahead Log Page (WAL) (Note: WAL functionality might be limited)
+
+## Technical Details
+
+*   **Language:** Pascal (Delphi).
+*   **Target:** Windows.
+*   **Approach:** Direct file I/O, parsing raw page structures according to Firebird Internal Format documentation (`fbint-page-1.html`) and Firebird source code conventions.
+*   **Modules:**
+    *   `uStructs`: Core data structures (TPag, THdr, etc.).
+    *   `uPageAnalyzer`: General page reading and type identification.
+    *   `uDataPage`: Data Page header parsing and record fragment extraction.
+    *   `uTipPage`: TIP page header parsing and transaction state analysis.
+    *   `uBtreePage`: B-Tree page header parsing and key extraction.
+    *   `uRecordParser`: *(New)* Parses headers of individual record fragments.
+    *   `uDatabaseStats`: Aggregates statistics using `uPageAnalyzer`.
+    *   `uFlagManager`: Manages database header flags.
 
 ## License
-MIT:
+
+MIT
 
 ## Author
+
 Gordienko Roman