A long-due cleanup + examples + things

..Obviously this breaks old things (particularly, see changes in
FocusElement).

1 files changed, 97 insertions, 0 deletions

diff --git a/util/Flushable.js b/util/Flushable.js
new file mode 100644
index 0000000..b031677
--- /dev/null
+++ b/util/Flushable.js
@@ -0,0 +1,97 @@
+const ansi = require('./ansi')
+
+module.exports = class Flushable {
+  // A writable that can be used to collect chunks of data before writing
+  // them.
+
+  constructor(writable, shouldCompress = false) {
+    this.target = writable
+
+    // Use the magical ANSI self-made compression method that probably
+    // doesn't *quite* work but should drastically decrease write size?
+    this.shouldCompress = shouldCompress
+
+    // Update these if you plan on using the ANSI compressor!
+    this.screenLines = 24
+    this.screenCols = 80
+
+    this.ended = false
+    this.paused = false
+    this.requestedFlush = false
+
+    this.chunks = []
+  }
+
+  write(what) {
+    this.chunks.push(what)
+  }
+
+  flush() {
+    // If we're paused, we don't want to write, but we will keep a note that a
+    // flush was requested for when we unpause.
+    if (this.paused) {
+      this.requestedFlush = true
+      return
+    }
+
+    // Don't write if we've ended.
+    if (this.ended) {
+      return
+    }
+
+    // End if the target is destroyed.
+    // Yes, this relies on the target having a destroyed property
+    // Don't worry, it'll still work if there is no destroyed property though
+    // (I think)
+    if (this.target.destroyed) {
+      this.end()
+      return
+    }
+
+    let toWrite = this.chunks.join('')
+
+    if (this.shouldCompress) {
+      toWrite = this.compress(toWrite)
+    }
+
+    try {
+      this.target.write(toWrite)
+    } catch(err) {
+      console.error('Flushable write error (ending):', err.message)
+      this.end()
+    }
+
+    this.chunks = []
+  }
+
+  pause() {
+    this.paused = true
+  }
+
+  resume() {
+    this.paused = false
+
+    if (this.requestedFlush) {
+      this.flush()
+    }
+  }
+
+  end() {
+    this.ended = true
+  }
+
+  compress(toWrite) {
+    // TODO: customize screen size
+    const screen = ansi.interpret(toWrite, this.screenLines, this.screenCols)
+
+    /*
+    const pcSaved = Math.round(100 - (100 / toWrite.length * screen.length))
+    console.log(
+      '\x1b[1A' +
+      `${toWrite.length} - ${screen.length} ${pcSaved}% saved   `
+    )
+    */
+
+    return screen
+  }
+}