From ccbedfa15079e17c24ec4cebee7f50689422611a Mon Sep 17 00:00:00 2001
From: Robert Smallshire <robert@smallshire.org.uk>
Date: Wed, 28 Jan 2015 21:50:04 +0100
Subject: [PATCH] High level SEG Y writer. Work in progress

---
 segpy/writer.py | 56 +++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 56 insertions(+)
 create mode 100644 segpy/writer.py

diff --git a/segpy/writer.py b/segpy/writer.py
new file mode 100644
index 0000000..cf3cedb
--- /dev/null
+++ b/segpy/writer.py
@@ -0,0 +1,56 @@
+from segpy.encoding import ASCII, is_supported_encoding, UnsupportedEncodingError
+from segpy.toolkit import (write_textual_reel_header, write_binary_reel_header, compile_trace_header_format,
+                           write_trace_header, write_trace_samples, format_extended_textual_header,
+                           write_extended_textual_headers)
+
+
+def write_segy(fh,
+               seg_y_data,
+               encoding=None,
+               endian='>',
+               progress=None):
+    """
+    Args:
+        fh: A file-like object open for binary write.
+
+        seg_y_data:  An object from which the headers and trace_samples data can be retrieved. Requires the following
+            properties and methods:
+              seg_y_data.textual_reel_header
+              seg_y_data.binary_reel_header
+              seg_y_data.extended_textual_header
+              seg_y_data.trace_indexes
+              seg_y_data.trace_header(trace_index)
+              seg_y_data.trace_samples(trace_index)
+
+              seg_y_data.encoding
+              seg_y_data.endian
+
+              One such legitimate object would be a SegYReader instance.
+
+        encoding: Optional encoding for text data. Typically 'cp037' for EBCDIC or 'ascii' for ASCII. If ommited, the
+            seg_y_data object will be queries for an encoding property.
+
+        endian: Big endian by default. If omitted, the seg_y_data object will be queried for an encoding property.
+
+        progress: An optional progress bar object.
+    """
+
+    encoding = encoding or (hasattr(seg_y_data, 'encoding') and seg_y_data.encoding) or ASCII
+
+    if not is_supported_encoding(encoding):
+        raise UnsupportedEncodingError("Writing SEG Y", encoding)
+
+    extended_header_pages = format_extended_textual_header(seg_y_data.extended_textual_header, encoding, include_text_stop=True)
+
+    write_textual_reel_header(fh, seg_y_data.textual_reel_header, encoding)
+    write_binary_reel_header(fh, seg_y_data.binary_reel_header, endian)
+    write_extended_textual_headers(fh, extended_header_pages, encoding)
+
+    trace_header_format = compile_trace_header_format(endian)
+
+    for trace_index in seg_y_data.trace_indexes:
+        write_trace_header(fh, seg_y_data.trace_header(trace_index), trace_header_format)
+        write_trace_samples(fh, seg_y_data.trace_samples(trace_index), seg_y_data.data_sample_format)
+
+
+