From 2d2cefb0b09686268a6418c28acd942a25302a15 Mon Sep 17 00:00:00 2001
From: Thomas Harte <thomas.harte@gmail.com>
Date: Wed, 2 Aug 2017 14:36:47 -0400
Subject: [PATCH] Adjusted factoring to introduce support for block 10.

---
 Storage/Tape/Formats/TZX.cpp | 64 +++++++++++++++++++++---------------
 Storage/Tape/Formats/TZX.hpp | 13 ++++++++
 2 files changed, 50 insertions(+), 27 deletions(-)

diff --git a/Storage/Tape/Formats/TZX.cpp b/Storage/Tape/Formats/TZX.cpp
index dba86f98d..efa3b3073 100644
--- a/Storage/Tape/Formats/TZX.cpp
+++ b/Storage/Tape/Formats/TZX.cpp
@@ -162,48 +162,58 @@ void TZX::get_generalised_segment(uint32_t output_symbols, uint8_t max_pulses_pe
 }
 
 void TZX::get_standard_speed_data_block() {
-	__unused uint16_t pause_after_block = fgetc16le();
-	uint16_t data_length = fgetc16le();
-	if(!data_length) return;
+	DataBlock data_block;
+	data_block.length_of_pilot_pulse = 2168;
+	data_block.length_of_sync_first_pulse = 667;
+	data_block.length_of_sync_second_pulse = 735;
+	data_block.length_of_zero_bit_pulse = 855;
+	data_block.length_of_one_bit_pulse = 1710;
+	data_block.number_of_bits_in_final_byte = 8;
+
+	data_block.pause_after_block = fgetc16le();
+	data_block.data_length = fgetc16le();
+	if(!data_block.data_length) return;
 
 	uint8_t first_byte = (uint8_t)fgetc(file_);
-	__unused int pilot_tone_pulses = (first_byte < 128) ? 8063  : 3223;
+	data_block.length_of_pilot_tone = (first_byte < 128) ? 8063  : 3223;
 	ungetc(first_byte, file_);
 
-	// TODO: output pilot_tone_pulses pulses
-	// TODO: output data_length bytes, in the Spectrum encoding
-	fseek(file_, data_length, SEEK_CUR);
-	// TODO: output a pause of length paused_after_block ms
+	get_data_block(data_block);
 }
 
 void TZX::get_turbo_speed_data_block() {
-	uint16_t length_of_pilot_pulse = fgetc16le();
-	uint16_t length_of_sync_first_pulse = fgetc16le();
-	uint16_t length_of_sync_second_pulse = fgetc16le();
-	uint16_t length_of_zero_bit_pulse = fgetc16le();
-	uint16_t length_of_one_bit_pulse = fgetc16le();
-	uint16_t length_of_pilot_tone = fgetc16le();
-	uint8_t number_of_bits_in_final_byte = (uint8_t)fgetc(file_);
-	uint16_t pause_after_block = fgetc16le();
-	long data_length = fgetc16le();
-	data_length |= (long)(fgetc(file_) << 16);
+	DataBlock data_block;
+	data_block.length_of_pilot_pulse = fgetc16le();
+	data_block.length_of_sync_first_pulse = fgetc16le();
+	data_block.length_of_sync_second_pulse = fgetc16le();
+	data_block.length_of_zero_bit_pulse = fgetc16le();
+	data_block.length_of_one_bit_pulse = fgetc16le();
+	data_block.length_of_pilot_tone = fgetc16le();
+	data_block.number_of_bits_in_final_byte = (uint8_t)fgetc(file_);
+	data_block.pause_after_block = fgetc16le();
+	data_block.data_length = fgetc16le();
+	data_block.data_length |= (long)(fgetc(file_) << 16);
 
+	get_data_block(data_block);
+}
+
+void TZX::get_data_block(const DataBlock &data_block) {
 	// Output pilot tone.
-	while(length_of_pilot_tone--) {
-		post_pulse(length_of_pilot_pulse);
+	for(unsigned int c = 0; c < data_block.length_of_pilot_tone; c++) {
+		post_pulse(data_block.length_of_pilot_pulse);
 	}
 
 	// Output sync pulses.
-	post_pulse(length_of_sync_first_pulse);
-	post_pulse(length_of_sync_second_pulse);
+	post_pulse(data_block.length_of_sync_first_pulse);
+	post_pulse(data_block.length_of_sync_second_pulse);
 
 	// Output data.
-	while(data_length--) {
+	for(unsigned int c = 0; c < data_block.data_length; c++) {
 		uint8_t next_byte = (uint8_t)fgetc(file_);
 
-		int c = data_length ? 8 : number_of_bits_in_final_byte;
-		while(c--) {
-			uint16_t pulse_length = (next_byte & 0x80) ? length_of_one_bit_pulse : length_of_zero_bit_pulse;
+		unsigned int bits = (c != data_block.data_length-1) ? 8 : data_block.number_of_bits_in_final_byte;
+		while(bits--) {
+			unsigned int pulse_length = (next_byte & 0x80) ? data_block.length_of_one_bit_pulse : data_block.length_of_zero_bit_pulse;
 			next_byte <<= 1;
 
 			post_pulse(pulse_length);
@@ -212,7 +222,7 @@ void TZX::get_turbo_speed_data_block() {
 	}
 
 	// Output gap.
-	post_gap(pause_after_block);
+	post_gap(data_block.pause_after_block);
 }
 
 void TZX::get_pure_tone_data_block() {
diff --git a/Storage/Tape/Formats/TZX.hpp b/Storage/Tape/Formats/TZX.hpp
index 97c5916b4..aeedf8ce9 100644
--- a/Storage/Tape/Formats/TZX.hpp
+++ b/Storage/Tape/Formats/TZX.hpp
@@ -44,7 +44,20 @@ class TZX: public PulseQueuedTape, public Storage::FileHolder {
 		void get_generalised_data_block();
 		void get_pause();
 
+		struct DataBlock {
+			unsigned int length_of_pilot_pulse;
+			unsigned int length_of_sync_first_pulse;
+			unsigned int length_of_sync_second_pulse;
+			unsigned int length_of_zero_bit_pulse;
+			unsigned int length_of_one_bit_pulse;
+			unsigned int length_of_pilot_tone;
+			unsigned int number_of_bits_in_final_byte;
+			unsigned int pause_after_block;
+			long data_length;
+		};
+
 		void get_generalised_segment(uint32_t output_symbols, uint8_t max_pulses_per_symbol, uint8_t number_of_symbols, bool is_data);
+		void get_data_block(const DataBlock &);
 
 		void post_pulse(unsigned int length);
 		void post_gap(unsigned int milliseconds);