fix!: rewrite bar reader to work with an user specified io.Reader (#5)

examples/reader.v

@@ -5,18 +5,30 @@ import os
 import time
 import bartender
 
-// This example shows the progress of writing content to an io.Writer (i.e., a file).
+// Example: Creating a bar reader from the file reader of `src_file` (with 500MiB dummy content)
+// and copying its contents to `dst_file`.
 fn main() {
-	mut start := time.ticks()
+	mut start := time.new_stopwatch()
 
-	// Create a reader with byte content to be written.
-	// In this example, 500 megabytes of dummy content.
-	mut r := bartender.bar_reader(bartender.Bar{}, '1234567890'.repeat(50 * 1024 * 1024).bytes())
-	mut f := os.create('testfile')!
-	io.cp(mut r, mut f)!
-	f.close()
+	src_file_path := './examples/dummy-src-file.txt'
+	dst_file_path := './examples/dummy-dst-file.txt'
 
-	println('Completed in ${f64(time.ticks() - start) / 1000:.2f}s')
-	// Cleanup - delete written file.
-	os.rm('testfile')!
+	os.write_file(src_file_path, '123456789\n'.repeat(50 * 1024 * 1024))!
+
+	mut src_file := os.open(src_file_path)!
+	mut dst_file := os.create(dst_file_path)!
+	defer {
+		src_file.close()
+		dst_file.close()
+		os.rm(src_file_path) or { panic(err) }
+		os.rm(dst_file_path) or { panic(err) }
+	}
+
+	bar := bartender.Bar{}
+	// Pass src_file as `io.Reader` to use it in a bar reader.
+	mut bar_reader := bar.reader(src_file, os.file_size(src_file_path))
+	// Use the `bar_reader`
+	io.cp(mut bar_reader, mut dst_file)!
+
+	println('Completed in ${start.elapsed()}')
 }

examples/reader_smooth.v

@@ -6,8 +6,36 @@ import time
 import term
 import bartender
 
+struct MyCustomReader {
+	size u64 [required]
+mut:
+	reader io.Reader [required]
+	pos    int
+}
+
+fn (mut r MyCustomReader) read(mut buf []u8) !int {
+	if r.pos >= r.size {
+		return io.Eof{}
+	}
+	n := r.reader.read(mut buf)!
+	r.pos += n
+	time.sleep(10 * time.millisecond)
+	return n
+}
+
 fn main() {
-	mut start := time.ticks()
+	// Prepare dummy files.
+	src_file_path := './examples/dummy-src-file.txt'
+	dst_file_path := './examples/dummy-dst-file.txt'
+	os.write_file(src_file_path, '123456789\n'.repeat(10 * 1024 * 1024))!
+	mut src_file := os.open(src_file_path)!
+	mut dst_file := os.create(dst_file_path)!
+	defer {
+		src_file.close()
+		dst_file.close()
+		os.rm(src_file_path) or { panic(err) }
+		os.rm(dst_file_path) or { panic(err) }
+	}
 
 	// Create a smooth bar. Apply customizations.
 	mut b := bartender.SmoothBar{
@@ -18,11 +46,11 @@ fn main() {
 	}
 	b.colorize(.cyan)
 
-	mut r := bartender.bar_reader(b, '1234567890'.repeat(50 * 1024 * 1024).bytes())
-	mut f := os.create('testfile')!
-	io.cp(mut r, mut f)!
-	f.close()
+	r := MyCustomReader{
+		reader: src_file
+		size: os.file_size(src_file_path)
+	}
 
-	println('Completed in ${f64(time.ticks() - start) / 1000:.2f}s')
-	os.rm('testfile')!
+	mut bar_reader := b.reader(r, r.size)
+	io.cp(mut bar_reader, mut dst_file)!
 }

src/_instructions_reader.v

@@ -2,35 +2,35 @@ module bartender
 
 import io
 
-const buf_max_len = 1024
+fn bar_reader(b BarType, reader io.Reader, size u64) &io.BufferedReader {
+	return io.new_buffered_reader(
+		reader: BarReader{
+			bar: b
+			reader: reader
+			size: size
+		}
+	)
+}
 
-fn bar_reader_(b BarType, bytes []u8) &io.BufferedReader {
-	return match b {
+fn (mut br BarReader) read(mut buf []u8) !int {
+	if br.pos >= br.size {
+		return io.Eof{}
+	}
+	n := br.reader.read(mut buf)!
+	br.pos += n
+	match mut br.bar {
+		// Unfortunately, comma separation doesn't work here ATM.
+		// SmoothBar won't be visible or will have corrupted chars.
 		Bar {
-			io.new_buffered_reader(
-				reader: BarReader{
-					bytes: bytes
-					size: bytes.len
-					bar: b
-				}
-			)
+			if (f64(br.pos) / br.size * br.bar.width) > br.bar.state.pos {
+				br.bar.progress()
+			}
 		}
 		SmoothBar {
-			io.new_buffered_reader(
-				reader: SmoothBarReader{
-					bytes: bytes
-					size: bytes.len
-					bar: b
-				}
-			)
+			if (f64(br.pos) / br.size * br.bar.width) > br.bar.state.pos {
+				br.bar.progress()
+			}
 		}
 	}
-}
-
-fn get_buf_end(r BarReaderType) int {
-	return if r.pos + bartender.buf_max_len >= r.size {
-		r.size
-	} else {
-		r.pos + bartender.buf_max_len
-	}
+	return n
 }

src/_instructions_simple_bar.v

@@ -2,7 +2,6 @@ module bartender
 
 import term
 import time
-import io
 import os
 
 fn (mut b Bar) setup() {
@@ -47,21 +46,6 @@ fn (b Bar) format() string {
 	return left + indicator + right
 }
 
-fn (mut r BarReader) read(mut buf []u8) !int {
-	if r.pos >= r.size {
-		return io.Eof{}
-	}
-
-	n := copy(mut buf, r.bytes[r.pos..get_buf_end(r)])
-	r.pos += n
-
-	if (f64(r.pos) / r.size * r.bar.width) > r.bar.pos() {
-		r.bar.progress()
-	}
-
-	return n
-}
-
 fn (mut b Bar) colorize_uni(color Color) {
 	b.runes_ = BarRunes_{
 		progress: color.paint(b.runes_.progress, .fg)

src/_instructions_smooth_bar.v

@@ -2,7 +2,6 @@ module bartender
 
 import term
 import time
-import io
 import os
 
 fn (mut b SmoothBar) setup() {
@@ -183,21 +182,6 @@ fn (b SmoothBar) format() string {
 	}
 }
 
-fn (mut r SmoothBarReader) read(mut buf []u8) !int {
-	if r.pos >= r.size {
-		return io.Eof{}
-	}
-
-	n := copy(mut buf, r.bytes[r.pos..get_buf_end(r)])
-	r.pos += n
-
-	if (f64(r.pos) / r.size * r.bar.width) > r.bar.pos() {
-		r.bar.progress()
-	}
-
-	return n
-}
-
 fn (b SmoothBar) next_pos() u16 {
 	return b.state.pos + u16(if b.theme_ == .push || b.theme_ == .pull {
 		1

src/_state_common.v

@@ -1,5 +1,7 @@
 module bartender
 
+import io
+
 struct BarBase {
 pub mut:
 	width u16 = 60
@@ -17,11 +19,12 @@ mut:
 	post_  string
 }
 
-struct BarReaderBase {
-	bytes []u8
-	size  int
+struct BarReader {
+	size u64
 mut:
-	pos int
+	bar    BarType
+	pos    int
+	reader io.Reader
 }
 
 struct State {
@@ -36,6 +39,4 @@ mut:
 
 type BarType = Bar | SmoothBar
 
-type BarReaderType = BarReader | SmoothBarReader
-
 type MultiBarType = []&Bar | []&SmoothBar

src/_state_simple.v

@@ -25,9 +25,3 @@ struct BarRunes_ {
 	indicator string
 	remaining string
 }
-
-struct BarReader {
-	BarReaderBase
-mut:
-	bar Bar
-}

src/_state_smooth.v

@@ -50,12 +50,6 @@ mut: // Strings instead of runes for color support.
 	sm []string // Smooth Mirrored. Used for merge, expand and split variant.
 }
 
-struct SmoothBarReader {
-	BarReaderBase
-mut:
-	bar SmoothBar
-}
-
 const (
 	smooth_ltr = [' ', '▏', '▎', '▍', '▌', '▋', '▊', '▉', '█']
 	smooth_rtl = ['█', '🮋', '🮊', '🮉', '▐', '🮈', '🮇', '▕', ' ']

src/lib.v

@@ -77,8 +77,8 @@ pub fn (mut b Bar) reset() {
 }
 
 // Returns a `io.BufferedReader` that displays a progressing bar when used in a reader operation.
-pub fn (mut b Bar) bar_reader(bytes []u8) &io.BufferedReader {
-	return bar_reader_(b, bytes)
+pub fn (b Bar) reader(reader io.Reader, size u64) &io.BufferedReader {
+	return bar_reader(b, reader, size)
 }
 
 // Monitors the progress of multiple bars until all of them are finished.
@@ -122,8 +122,8 @@ pub fn (mut b SmoothBar) reset() {
 }
 
 // Returns a `io.BufferedReader` that displays a progressing bar when used in a reader operation.
-pub fn (mut b SmoothBar) bar_reader(bytes []u8) &io.BufferedReader {
-	return bar_reader_(b, bytes)
+pub fn (b SmoothBar) reader(reader io.Reader, size u64) &io.BufferedReader {
+	return bar_reader(b, reader, size)
 }
 
 // Monitors the progress of multiple bars until all of them are finished.
@@ -133,10 +133,6 @@ pub fn (bars []&SmoothBar) watch(mut wg sync.WaitGroup) {
 
 // == Misc ====================================================================
 
-pub fn bar_reader(b BarType, bytes []u8) &io.BufferedReader {
-	return bar_reader_(b, bytes)
-}
-
 // Returns the bar's current position.
 pub fn (b BarBase) pos() u16 {
 	return b.state.pos