From 0485580b899007368f95822e21067bc0763f01b2 Mon Sep 17 00:00:00 2001
From: Ian Gulliver <ian@flamingcow.tv>
Date: Thu, 11 Jul 2019 22:30:53 +0000
Subject: [PATCH] Proper history tracking

---
 Architype.js   | 68 +++++++++++++++++++++++++++++++++++++++++++++-----
 EditorLabel.js | 15 +++++++++--
 EditorNode.js  | 16 ++++++++++--
 IdSource.js    |  4 +++
 4 files changed, 93 insertions(+), 10 deletions(-)

diff --git a/Architype.js b/Architype.js
index 3d4a1d4..c9356f8 100644
--- a/Architype.js
+++ b/Architype.js
@@ -33,28 +33,56 @@ class Architype {
       this.render_.push(render);
     }
 
-    this.unserialize(JSON.parse(localStorage.getItem('currentState')));
+    addEventListener('hashchange', (e) => { this.onHashChange(e); });
+
+    let fixUrl = false;
+    if (location.hash.length > 1) {
+      this.unserialize(JSON.parse(atob(location.hash.substring(1))));
+    } else {
+      this.unserialize(JSON.parse(localStorage.getItem('currentState')));
+      fixUrl = true;
+    }
     if (this.editor_.getEntries().length == 0) {
       this.editor_.addHelpAfter();
     }
     this.editor_.selectNext();
 
     this.observer_ = new MutationObserver(e => { this.onChange(e); });
+    this.observer2_ = new MutationObserver(e => { this.snapshot(e); });
+    this.observe();
+
+    this.saveAndRender();
+
+    if (fixUrl) {
+      history.replaceState(null, null, '#' + btoa(this.serializedStr_));
+    }
+  }
+
+  observe() {
     this.observer_.observe(this.editorElem_, {
       attributes: true,
       attributeFilter: ['data-arch-refresh'],
       childList: true,
       subtree: true,
     });
+    this.observer2_.observe(this.editorElem_, {
+      attributes: true,
+      attributeFilter: ['data-arch-snapshot'],
+      childList: true,
+      subtree: true,
+    });
+  }
 
-    this.onChange();
+  unobserve() {
+    this.observer_.disconnect();
+    this.observer2_.disconnect();
   }
 
   serialize() {
     return {
       version: 1,
-      generation: ++this.generation_,
-      nextId: idSource.getId(),
+      generation: this.generation_,
+      nextId: idSource.peekId(),
       editor: this.editor_.serialize(),
     };
   }
@@ -64,6 +92,9 @@ class Architype {
       return;
     }
 
+    this.renderGeneration_ = -1;
+    this.drawGeneration_ = -1;
+
     switch (ser.version) {
       case 1:
         this.generation_ = ser.generation;
@@ -77,10 +108,35 @@ class Architype {
     }
   }
 
-  onChange(e) {
+  overwrite(ser) {
+    this.unobserve();
+    this.editor_.clear();
+    this.unserialize(ser);
+    this.observe();
+    this.editor_.selectNext();
+    this.saveAndRender();
+  }
+
+  onHashChange() {
+    if (location.hash.length > 1) {
+      this.overwrite(JSON.parse(atob(location.hash.substring(1))));
+    }
+  }
+
+  onChange() {
+    ++this.generation_;
+    this.saveAndRender();
+  }
+
+  snapshot() {
+    history.pushState(null, null, '#' + btoa(this.serializedStr_));
+  }
+
+  saveAndRender() {
     this.serialized_ = this.serialize();
     this.startRender();
-    localStorage.setItem('currentState', JSON.stringify(this.serialized_));
+    this.serializedStr_ = JSON.stringify(this.serialized_);
+    localStorage.setItem('currentState', this.serializedStr_);
   }
 
   onKeyDown(e) {
diff --git a/EditorLabel.js b/EditorLabel.js
index 025361b..a5f54fd 100644
--- a/EditorLabel.js
+++ b/EditorLabel.js
@@ -9,8 +9,11 @@ class EditorLabel extends EditorEntryBase {
     this.input_.type = 'text';
     this.input_.placeholder = 'label';
     this.listen(this.input_, 'keydown', (e) => this.onInputKeyDown(e));
-    this.listen(this.input_, 'input', (e) => this.onInput());
+    this.listen(this.input_, 'input', (e) => this.onInput(e));
+    this.listen(this.input_, 'blur', (e) => this.onBlur(e));
     this.elem_.appendChild(this.input_);
+
+    this.lastSnapshotLabel_ = null;
   }
 
   afterDomAdd() {
@@ -30,6 +33,7 @@ class EditorLabel extends EditorEntryBase {
 
   setLabel(label) {
     this.input_.value = label;
+    this.lastSnapshotLabel_ = label;
     this.onInput();
   }
 
@@ -38,7 +42,14 @@ class EditorLabel extends EditorEntryBase {
   }
 
   onInput() {
-    this.input_.setAttribute('data-arch-refresh', '');
+    this.elem_.setAttribute('data-arch-refresh', '');
+  }
+
+  onBlur() {
+    if (this.getLabel() != this.lastSnapshotLabel_) {
+      this.lastSnapshotLabel_ = this.getLabel();
+      this.elem_.setAttribute('data-arch-snapshot', '');
+    }
   }
 
   onInputKeyDown(e) {
diff --git a/EditorNode.js b/EditorNode.js
index 2c3c50c..e16ca12 100644
--- a/EditorNode.js
+++ b/EditorNode.js
@@ -8,9 +8,12 @@ class EditorNode extends EditorEntryBase {
     this.input_.type = 'text';
     this.input_.placeholder = 'node name';
     this.listen(this.input_, 'keydown', (e) => this.onInputKeyDown(e));
-    this.listen(this.input_, 'input', (e) => this.onInput());
+    this.listen(this.input_, 'input', (e) => this.onInput(e));
+    this.listen(this.input_, 'blur', (e) => this.onBlur(e));
     this.elem_.appendChild(this.input_);
 
+    this.lastSnapshotLabel_ = null;
+
     if (label) {
       this.setLabel(label);
     }
@@ -35,6 +38,7 @@ class EditorNode extends EditorEntryBase {
 
   setLabel(label) {
     this.input_.value = label;
+    this.lastSnapshotLabel_ = label;
     this.onInput();
   }
 
@@ -58,7 +62,15 @@ class EditorNode extends EditorEntryBase {
   }
 
   onInput() {
-    this.input_.setAttribute('data-arch-refresh', '');
+    this.elem_.setAttribute('data-arch-refresh', '');
+  }
+
+  onBlur() {
+    if (this.getLabel() != this.lastSnapshotLabel_) {
+      console.log('changed');
+      this.lastSnapshotLabel_ = this.getLabel();
+      this.elem_.setAttribute('data-arch-snapshot', '');
+    }
   }
 
   onInputKeyDown(e) {
diff --git a/IdSource.js b/IdSource.js
index 4fec2b2..aa0dda5 100644
--- a/IdSource.js
+++ b/IdSource.js
@@ -7,6 +7,10 @@ class IdSource {
     return ++this.nextId_;
   }
 
+  peekId() {
+    return this.nextId_;
+  }
+
   setId(nextId) {
     this.nextId_ = nextId;
   }