Add automatic coloring of tags

Please see this as proposal on how to implement automatic/random colors
for tags while keeping the current set of hard coded colors in place (at
least in the frontend).

Bear with me as I have even less Angular knowledge than Django and just
tried to get away with as few changes as possible. :-) AIUI you want to
change to a color picking system anyways in the future, which could also
play well with this.

fixes #51

Pipfile

@@ -40,6 +40,7 @@ whoosh="~=2.7.4"
 inotifyrecursive = ">=0.3.4"
 ocrmypdf = "*"
 tqdm = "*"
+colorhash = "*"
 
 [dev-packages]
 coveralls = "*"

src-ui/src/app/components/common/tag/tag.component.html

@@ -1,2 +1,2 @@
-<span *ngIf="!clickable" class="badge" [style.background]="getColour().value" [style.color]="getColour().textColor">{{tag.name}}</span>
-<a [routerLink]="" [title]="linkTitle" *ngIf="clickable" class="badge" [style.background]="getColour().value" [style.color]="getColour().textColor">{{tag.name}}</a>
+<span *ngIf="!clickable" class="badge" [style.background]="getColour().id" [style.color]="getColour().textColor">{{tag.name}}</span>
+<a [routerLink]="" [title]="linkTitle" *ngIf="clickable" class="badge" [style.background]="getColour().id" [style.color]="getColour().textColor">{{tag.name}}</a>

src-ui/src/app/components/common/tag/tag.component.ts

@@ -23,7 +23,11 @@ export class TagComponent implements OnInit {
   }
 
   getColour() {
-    return TAG_COLOURS.find(c => c.id == this.tag.colour)
+    var color = TAG_COLOURS.find(c => c.id == this.tag.colour)
+    if (color) {
+      return color
+    }
+    return { id: this.tag.colour, name: this.tag.colour, textColor: "#ffffff" }
   }
 
 }

src-ui/src/app/components/manage/tag-list/tag-edit-dialog/tag-edit-dialog.component.html

@@ -7,7 +7,7 @@
     </div>
     <div class="modal-body">
       <app-input-text title="Name" formControlName="name"></app-input-text>
-      <app-input-select title="Colour" [items]="getColours()" formControlName="colour" [textColor]="getColor(objectForm.value.colour).textColor" [backgroundColor]="getColor(objectForm.value.colour).value"></app-input-select>
+      <app-input-select title="Colour" [items]="getColours()" formControlName="colour" [textColor]="getColor(objectForm.value.colour).textColor" [backgroundColor]="getColor(objectForm.value.colour).id"></app-input-select>
       <app-input-check title="Inbox tag" formControlName="is_inbox_tag" hint="Inbox tags are automatically assigned to all consumed documents."></app-input-check>
       <app-input-text title="Match" formControlName="match"></app-input-text>
       <app-input-select title="Matching algorithm" [items]="getMatchingAlgorithms()" formControlName="matching_algorithm"></app-input-select>

src-ui/src/app/components/manage/tag-list/tag-edit-dialog/tag-edit-dialog.component.ts

@@ -20,7 +20,7 @@ export class TagEditDialogComponent extends EditDialogComponent<PaperlessTag> {
   getForm(): FormGroup {
     return new FormGroup({
       name: new FormControl(''),
-      colour: new FormControl(1),
+      colour: new FormControl(''),
       is_inbox_tag: new FormControl(false),
       matching_algorithm: new FormControl(1),
       match: new FormControl(""),
@@ -32,7 +32,7 @@ export class TagEditDialogComponent extends EditDialogComponent<PaperlessTag> {
     return TAG_COLOURS
   }
 
-  getColor(id: number) {
+  getColor(id) {
     return TAG_COLOURS.find(c => c.id == id)
   }
 

src-ui/src/app/components/manage/tag-list/tag-list.component.html

@@ -23,7 +23,7 @@
     <tr *ngFor="let tag of data">
       <td scope="row">{{ tag.name }}</td>
       <td scope="row"><span class="badge" [style.color]="getColor(tag.colour).textColor"
-          [style.background-color]="getColor(tag.colour).value">{{ getColor(tag.colour).name }}</span></td>
+          [style.background-color]="tag.colour">{{ getColor(tag.colour).name }}</span></td>
       <td scope="row">{{ getMatching(tag) }}</td>
       <td scope="row">{{ tag.document_count }}</td>
       <td scope="row">

src-ui/src/app/components/manage/tag-list/tag-list.component.ts

@@ -15,10 +15,14 @@ export class TagListComponent extends GenericListComponent<PaperlessTag> {
 
   constructor(tagService: TagService, modalService: NgbModal) {
     super(tagService, modalService, TagEditDialogComponent)
-   }
+  }
 
   getColor(id) {
-    return TAG_COLOURS.find(c => c.id == id)
+    var color = TAG_COLOURS.find(c => c.id == id)
+    if (color) {
+      return color
+    }
+    return { id: id, name: id, textColor: "#ffffff" }
   }
 
   getObjectName(object: PaperlessTag) {

src-ui/src/app/data/paperless-tag.ts

@@ -3,24 +3,25 @@ import { ObjectWithId } from './object-with-id';
 
 
 export const TAG_COLOURS = [
-    {id: 1, value: "#a6cee3", name: "Light Blue", textColor: "#000000"},
-    {id: 2, value: "#1f78b4", name: "Blue", textColor: "#ffffff"},
-    {id: 3, value: "#b2df8a", name: "Light Green", textColor: "#000000"},
-    {id: 4, value: "#33a02c", name: "Green", textColor: "#000000"},
-    {id: 5, value: "#fb9a99", name: "Light Red", textColor: "#000000"},
-    {id: 6, value: "#e31a1c", name: "Red ", textColor: "#ffffff"},
-    {id: 7, value: "#fdbf6f", name: "Light Orange", textColor: "#000000"},
-    {id: 8, value: "#ff7f00", name: "Orange", textColor: "#000000"},
-    {id: 9, value: "#cab2d6", name: "Light Violet", textColor: "#000000"},
-    {id: 10, value: "#6a3d9a", name: "Violet", textColor: "#ffffff"},
-    {id: 11, value: "#b15928", name: "Brown", textColor: "#000000"},
-    {id: 12, value: "#000000", name: "Black", textColor: "#ffffff"},
-    {id: 13, value: "#cccccc", name: "Light Grey", textColor: "#000000"}
+    { id: "", name: "Auto", textColor: "#000000" },
+    { id: "#a6cee3", name: "Light Blue", textColor: "#000000" },
+    { id: "#1f78b4", name: "Blue", textColor: "#ffffff" },
+    { id: "#b2df8a", name: "Light Green", textColor: "#000000" },
+    { id: "#33a02c", name: "Green", textColor: "#000000" },
+    { id: "#fb9a99", name: "Light Red", textColor: "#000000" },
+    { id: "#e31a1c", name: "Red ", textColor: "#ffffff" },
+    { id: "#fdbf6f", name: "Light Orange", textColor: "#000000" },
+    { id: "#ff7f00", name: "Orange", textColor: "#000000" },
+    { id: "#cab2d6", name: "Light Violet", textColor: "#000000" },
+    { id: "#6a3d9a", name: "Violet", textColor: "#ffffff" },
+    { id: "#b15928", name: "Brown", textColor: "#000000" },
+    { id: "#000000", name: "Black", textColor: "#ffffff" },
+    { id: "#cccccc", name: "Light Grey", textColor: "#000000" }
 ]
 
 export interface PaperlessTag extends MatchingModel {
 
-    colour?: number
+    colour?: string
 
     is_inbox_tag?: boolean
 

src/documents/migrations/1006_migrate_tag_colour.py

@@ -0,0 +1,70 @@
+# Generated by Django 3.1.4 on 2020-12-02 21:43
+
+from django.db import migrations, models
+
+COLOURS_OLD = {
+    1: "#a6cee3",
+    2: "#1f78b4",
+    3: "#b2df8a",
+    4: "#33a02c",
+    5: "#fb9a99",
+    6: "#e31a1c",
+    7: "#fdbf6f",
+    8: "#ff7f00",
+    9: "#cab2d6",
+    10: "#6a3d9a",
+    11: "#b15928",
+    12: "#000000",
+    13: "#cccccc",
+}
+
+
+def forward(apps, schema_editor):
+    Tag = apps.get_model('documents', 'Tag')
+
+    for tag in Tag.objects.all():
+        colour_old_id = tag.colour_old
+        rgb = COLOURS_OLD[colour_old_id]
+        tag.colour = rgb
+        tag.save()
+
+
+def reverse(apps, schema_editor):
+    Tag = apps.get_model('documents', 'Tag')
+
+    def _get_colour_id(rdb):
+        for idx, rdbx in COLOURS_OLD.items():
+            if rdbx == rdb:
+                return idx
+        # Return colour 1 if we can't match anything
+        return 1
+
+    for tag in Tag.objects.all():
+        colour_id = _get_colour_id(tag.colour)
+        tag.colour_old = colour_id
+        tag.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('documents', '1005_checksums'),
+    ]
+
+    operations = [
+        migrations.RenameField(
+            model_name='tag',
+            old_name='colour',
+            new_name='colour_old',
+        ),
+        migrations.AddField(
+            model_name='tag',
+            name='colour',
+            field=models.CharField(blank=True, max_length=7),
+        ),
+        migrations.RunPython(forward, reverse),
+        migrations.RemoveField(
+            model_name='tag',
+            name='colour_old',
+        )
+    ]

src/documents/models.py

@@ -6,6 +6,7 @@ import re
 from collections import OrderedDict
 
 import dateutil.parser
+from colorhash import ColorHash
 from django.conf import settings
 from django.db import models
 from django.utils import timezone
@@ -84,23 +85,7 @@ class Correspondent(MatchingModel):
 
 class Tag(MatchingModel):
 
-    COLOURS = (
-        (1, "#a6cee3"),
-        (2, "#1f78b4"),
-        (3, "#b2df8a"),
-        (4, "#33a02c"),
-        (5, "#fb9a99"),
-        (6, "#e31a1c"),
-        (7, "#fdbf6f"),
-        (8, "#ff7f00"),
-        (9, "#cab2d6"),
-        (10, "#6a3d9a"),
-        (11, "#b15928"),
-        (12, "#000000"),
-        (13, "#cccccc")
-    )
-
-    colour = models.PositiveIntegerField(choices=COLOURS, default=1)
+    colour = models.CharField(blank=True, max_length=7)
 
     is_inbox_tag = models.BooleanField(
         default=False,
@@ -108,6 +93,15 @@ class Tag(MatchingModel):
                   "documents will be tagged with inbox tags."
     )
 
+    def save(self, *args, **kwargs):
+        if self.colour == "":
+            self.colour = ColorHash(
+                self.name,
+                lightness=(0.35, 0.45, 0.55, 0.65),
+                saturation=(0.2, 0.3, 0.4, 0.5)).hex
+
+        super().save(*args, **kwargs)
+
 
 class DocumentType(MatchingModel):