add backend functionality

common/utils.py

@@ -1,8 +1,9 @@
 from random import choices
 from string import ascii_lowercase
-from typing import Any
+from typing import Any, Callable
 
 from django.template.loader import render_to_string
+from django.urls import NoReverseMatch, reverse
 from django.utils.safestring import mark_safe
 
 
@@ -31,16 +32,68 @@ HTMLAttribute = tuple[str, str]
 HTMLTag = str
 
 
-def A(attributes: list[HTMLAttribute], children: list[HTMLTag] | HTMLTag) -> HTMLTag:
+def Component(
+    attributes: list[HTMLAttribute] = [],
+    children: list[HTMLTag] | HTMLTag = [],
+    template: str = "",
+    tag_name: str = "",
+) -> HTMLTag:
+    if not tag_name and not template:
+        raise ValueError("One of template or tag_name is required.")
     if isinstance(children, str):
         children = [children]
     childrenBlob = "\n".join(children)
     attributesList = [f'{name} = "{value}"' for name, value in attributes]
     attributesBlob = " ".join(attributesList)
-    tag: str = f"<a {attributesBlob}>{childrenBlob}</a>"
+    tag: str = ""
+    if tag_name != "":
+        tag = f"<a {attributesBlob}>{childrenBlob}</a>"
+    elif template != "":
+        tag = render_to_string(
+            template,
+            {name: value for name, value in attributes} | {"slot": "\n".join(children)},
+        )
     return mark_safe(tag)
 
 
+def A(
+    attributes: list[HTMLAttribute] = [],
+    children: list[HTMLTag] | HTMLTag = [],
+    url: str | Callable[..., Any] = "",
+):
+    """
+    Returns the HTML tag "a".
+    "url" can either be:
+        - URL (string)
+        - path name passed to reverse() (string)
+        - function
+    """
+    additional_attributes = []
+    if url:
+        if type(url) is str:
+            try:
+                url_result = reverse(url)
+            except NoReverseMatch:
+                url_result = url
+        elif callable(url):
+            url_result = url()
+        else:
+            raise TypeError("'url' is neither str nor function.")
+        additional_attributes = [("href", url_result)]
+    return Component(
+        tag_name="a", attributes=attributes + additional_attributes, children=children
+    )
+
+
+def Button(
+    attributes: list[HTMLAttribute] = [],
+    children: list[HTMLTag] | HTMLTag = [],
+):
+    return Component(
+        template="cotton/button.html", attributes=attributes, children=children
+    )
+
+
 def safe_division(numerator: int | float, denominator: int | float) -> int | float:
     """
     Divides without triggering division by zero exception.

games/templates/cotton/button.html

@@ -1,4 +1,5 @@
 <button type="button"
         class="text-white bg-blue-700 hover:bg-blue-800 focus:ring-4 focus:ring-blue-300 font-medium rounded-lg text-sm px-5 py-2.5 me-2 mb-2 mt-2 dark:bg-blue-600 dark:hover:bg-blue-700 focus:outline-none dark:focus:ring-blue-800">
     {{ text }}
+    {{ slot }}
 </button>

games/templates/cotton/simple_table.html

@@ -2,6 +2,11 @@
 <div class="shadow-md sm:rounded-lg" hx-boost="false">
     <div class="relative overflow-x-auto sm:rounded-lg">
         <table class="w-full text-sm text-left rtl:text-right text-gray-500 dark:text-gray-400">
+            {% if header_action %}
+                <c-table-header>
+                {{ header_action }}
+                </c-table-header>
+            {% endif %}
             <thead class="text-xs text-gray-700 uppercase bg-gray-50 dark:bg-gray-700 dark:text-gray-400">
                 <tr>
                     {% for column in columns %}<th scope="col" class="px-6 py-3">{{ column }}</th>{% endfor %}

games/templates/cotton/table_header.html

@@ -0,0 +1,3 @@
+<caption class="p-2 text-lg font-semibold rtl:text-left text-right text-gray-900 bg-white dark:text-white dark:bg-gray-900">
+    {{ slot }}
+</caption>

games/templates/list_purchases.html

@@ -5,6 +5,6 @@
 {% endblock title %}
 {% block content %}
     <div class="2xl:max-w-screen-2xl md:max-w-screen-md sm:max-w-screen-sm self-center">
-        <c-simple-table :columns=data.columns :rows=data.rows :page_obj=page_obj :elided_page_range=elided_page_range />
+        <c-simple-table :columns=data.columns :rows=data.rows :page_obj=page_obj :elided_page_range=elided_page_range :header_action=data.header_action />
     </div>
 {% endblock content %}

games/views/device.py

@@ -7,6 +7,7 @@ from django.shortcuts import get_object_or_404, redirect, render
 from django.template.loader import render_to_string
 from django.urls import reverse
 
+from common.utils import A, Button
 from games.forms import DeviceForm
 from games.models import Device
 from games.views.general import dateformat
@@ -35,6 +36,7 @@ def list_devices(request: HttpRequest) -> HttpResponse:
             else None
         ),
         "data": {
+            "header_action": A([], Button([], "Add device"), url="add_device"),
             "columns": [
                 "Name",
                 "Type",

games/views/edition.py

@@ -7,7 +7,7 @@ from django.shortcuts import get_object_or_404, redirect, render
 from django.template.loader import render_to_string
 from django.urls import reverse
 
-from common.utils import A, truncate_with_popover
+from common.utils import A, Button, truncate_with_popover
 from games.forms import EditionForm
 from games.models import Edition, Game
 from games.views.general import dateformat
@@ -36,6 +36,7 @@ def list_editions(request: HttpRequest) -> HttpResponse:
             else None
         ),
         "data": {
+            "header_action": A([], Button([], "Add edition"), url="add_edition"),
             "columns": [
                 "Game",
                 "Name",

games/views/game.py

@@ -9,7 +9,7 @@ from django.template.loader import render_to_string
 from django.urls import reverse
 
 from common.time import format_duration
-from common.utils import A, safe_division, truncate_with_popover
+from common.utils import A, Button, safe_division, truncate_with_popover
 from games.forms import GameForm
 from games.models import Edition, Game, Purchase, Session
 from games.views.general import (
@@ -45,6 +45,7 @@ def list_games(request: HttpRequest) -> HttpResponse:
             else None
         ),
         "data": {
+            "header_action": A([], Button([], "Add game"), url="add_game"),
             "columns": [
                 "Name",
                 "Sort Name",

games/views/platform.py

@@ -7,6 +7,7 @@ from django.shortcuts import get_object_or_404, redirect, render
 from django.template.loader import render_to_string
 from django.urls import reverse
 
+from common.utils import A, Button
 from games.forms import PlatformForm
 from games.models import Platform
 from games.views.general import dateformat, use_custom_redirect
@@ -35,6 +36,7 @@ def list_platforms(request: HttpRequest) -> HttpResponse:
             else None
         ),
         "data": {
+            "header_action": A([], Button([], "Add platform"), url="add_platform"),
             "columns": [
                 "Name",
                 "Group",

games/views/purchase.py

@@ -13,7 +13,7 @@ from django.template.loader import render_to_string
 from django.urls import reverse
 from django.utils import timezone
 
-from common.utils import A, truncate_with_popover
+from common.utils import A, Button, truncate_with_popover
 from games.forms import PurchaseForm
 from games.models import Edition, Purchase
 from games.views.general import dateformat, use_custom_redirect
@@ -42,6 +42,7 @@ def list_purchases(request: HttpRequest) -> HttpResponse:
             else None
         ),
         "data": {
+            "header_action": A([], Button([], "Add purchase"), url="add_purchase"),
             "columns": [
                 "Name",
                 "Platform",

games/views/session.py

@@ -1,15 +1,22 @@
-from typing import Any
+import operator
+from functools import reduce
+from json import dumps as json_dumps
+from json import loads as json_loads
+from typing import Any, NotRequired, TypeAlias, TypedDict, TypeGuard
 
 from django.contrib.auth.decorators import login_required
 from django.core.paginator import Paginator
+from django.db.models.query import QuerySet
+from django.db.models.query_utils import Q
 from django.http import HttpRequest, HttpResponse
 from django.shortcuts import get_object_or_404, redirect, render
 from django.template.loader import render_to_string
 from django.urls import reverse
 from django.utils import timezone
+from typing_extensions import TypeGuard
 
 from common.time import format_duration
-from common.utils import A, truncate_with_popover
+from common.utils import A, Button, truncate_with_popover
 from games.forms import SessionForm
 from games.models import Purchase, Session
 from games.views.general import (
@@ -22,12 +29,283 @@ from games.views.general import (
 )
 
 
+class Filter(TypedDict):
+    filter_id: str
+    filter_display: str
+    filter_string: str
+
+
+def is_filter(obj: dict[Any, Any]) -> TypeGuard[Filter]:
+    return (
+        isinstance(obj, dict)
+        and "filter_id" in obj
+        and isinstance(obj["filter_id"], str)
+        and "filter_display" in obj
+        and isinstance(obj["filter_display"], str)
+        and "filter_string" in obj
+        and isinstance(obj["filter_string"], str)
+    )
+
+
+FilterList: TypeAlias = list[Filter]
+
+
+def is_filterlist(obj: list[Any]) -> TypeGuard[FilterList]:
+    return isinstance(obj, list) and all([is_filter(item) for item in obj])
+
+
+ModelFilterSet: TypeAlias = list[dict[str, FilterList]]
+
+
+class FieldFilter(TypedDict):
+    filtered_field: str
+    filtered_value: str
+    negated: NotRequired[bool]
+    filter: Filter
+
+
+def is_fieldfilter(obj: dict) -> TypeGuard[FieldFilter]:
+    return (
+        isinstance(obj, dict)
+        and "filtered_field" in obj
+        and isinstance(obj["filtered_field"], str)
+        and "filtered_value" in obj
+        and isinstance(obj["filtered_value"], str)
+        and "filter" in obj
+        and is_filter(obj["filter"])
+    )
+
+
+FilterSet: TypeAlias = list[FieldFilter]
+
+
+def is_filterset(obj: list) -> TypeGuard[FilterSet]:
+    return isinstance(obj, list) and all([is_fieldfilter(item) for item in obj])
+
+
+iexact_filter: Filter = {
+    "filter_id": "IEXACT",
+    "filter_display": "Equals (case-insensitive)",
+    "filter_string": "__iexact",
+}
+exact_filter: Filter = {
+    "filter_id": "EXACT",
+    "filter_display": "Equals (case-sensitive)",
+    "filter_string": "__exact",
+}
+isnull_filter: Filter = {
+    "filter_id": "ISNULL",
+    "filter_display": "Is null",
+    "filter_string": "__isnull",
+}
+contains_filter: Filter = {
+    "filter_id": "CONTAINS",
+    "filter_display": "Contains",
+    "filter_string": "__contains",
+}
+startswith_filter: Filter = {
+    "filter_id": "STARTSWITH",
+    "filter_display": "Starts with",
+    "filter_string": "__startswith",
+}
+endswith_filter: Filter = {
+    "filter_id": "ENDSWITH",
+    "filter_display": "Ends with",
+    "filter_string": "__endswith",
+}
+gt_filter: Filter = {
+    "filter_id": "GT",
+    "filter_display": "Greater than",
+    "filter_string": "__gt",
+}
+lt_filter: Filter = {
+    "filter_id": "LT",
+    "filter_display": "Lesser than",
+    "filter_string": "__lt",
+}
+year_gt_filter: Filter = {
+    "filter_id": "YEARGT",
+    "filter_display": "Greater than",
+    "filter_string": "__year__gt",
+}
+year_lt_filter: Filter = {
+    "filter_id": "YEARLT",
+    "filter_display": "Lesser than",
+    "filter_string": "__year__lt",
+}
+year_exact_filter: Filter = {
+    "filter_id": "YEAREXACT",
+    "filter_display": "Equals (case-sensitive)",
+    "filter_string": "__year__exact",
+}
+
+defined_filters = [
+    iexact_filter,
+    exact_filter,
+    isnull_filter,
+    contains_filter,
+    startswith_filter,
+    endswith_filter,
+    gt_filter,
+    lt_filter,
+    year_gt_filter,
+    year_lt_filter,
+    year_exact_filter,
+]
+
+defined_filters_list = {list["filter_id"]: list for list in defined_filters}
+
+char_filter: FilterList = [
+    iexact_filter,
+    isnull_filter,
+    contains_filter,
+    startswith_filter,
+    endswith_filter,
+]
+text_filter: FilterList = [
+    isnull_filter,
+    contains_filter,
+]
+num_filter: FilterList = [exact_filter, gt_filter, lt_filter]
+date_filter: FilterList = [
+    year_exact_filter,
+    isnull_filter,
+    year_gt_filter,
+    year_lt_filter,
+]
+
+conditions = ["and", "or"]
+session_filters: ModelFilterSet = [
+    {"name": char_filter},
+    {"timestamp_start": date_filter},
+    {"timestamp_end": date_filter},
+    {"duration_manual": num_filter},
+    {"duration_calculated": num_filter},
+    {"note": text_filter},
+    {"device": char_filter},
+    {"created_at": date_filter},
+    {"modified_at": date_filter},
+]
+name_contains_age: FieldFilter = {
+    "filtered_field": "name",
+    "filtered_value": "age",
+    "filter": contains_filter,
+}
+simple_example_filter: FilterSet = [name_contains_age]
+timestamp_start_year_2024: FieldFilter = {
+    "filtered_field": "timestamp_start",
+    "filtered_value": "2024",
+    "filter": year_exact_filter,
+}
+physical_only: FieldFilter = {
+    "filtered_field": "purchase__ownership_type",
+    "filtered_value": "ph",
+    "filter": exact_filter,
+}
+
+
+def negate_filter(filter: FieldFilter) -> FieldFilter:
+    return {**filter, "negated": True}
+
+
+without_physical: FieldFilter = negate_filter(physical_only)
+combined_example_filter: FilterSet = [name_contains_age, timestamp_start_year_2024]
+combined_with_negated_example_filter = [timestamp_start_year_2024, without_physical]
+
+
+def string_to_dict(s: str) -> dict[str, str]:
+    key, value = s.split("=")
+    return {key: value}
+
+
+def create_django_filter_dict(
+    filter: Filter, field: str, filtered_value: str
+) -> dict[str, str]:
+    """
+    Creates a dict that can be used with the Django
+    filter function by unpacking it:
+    Model.objects.filter(**return_value)
+    """
+    if not is_filter(filter):
+        raise ValueError("filter is not of type Filter")
+    return {f"{field}{filter["filter_string"]}": filtered_value}
+
+
+def join_filter_with_condition(filters: FilterSet, condition: str):
+    if not is_filterset(filters):
+        raise ValueError("filters is not FilterSet")
+    conditions = {"AND": operator.and_, "OR": operator.or_, "XOR": operator.xor}
+    condition = condition.upper()
+    if condition not in conditions:
+        raise ValueError(f"Condition '{condition}' not one of '{conditions.keys()}'.")
+    q_objects: list[Q] = []
+    for filter_item in filters:
+        q = Q(
+            **create_django_filter_dict(
+                filter_item["filter"],
+                filter_item["filtered_field"],
+                filter_item["filtered_value"],
+            )
+        )
+        if filter_item.get("negated", False):
+            q = ~q
+        q_objects.append(q)
+    return reduce(conditions[condition], q_objects)
+
+
+def apply_filters(
+    filters: FilterSet,
+    queryset: QuerySet[Any],
+) -> QuerySet[Any] | None:
+    if len(filters) == 0:
+        return queryset
+    if type(filters) is not list:
+        raise ValueError("filters argument not of type list")
+    # TODO: modify FilterSet so it includes the condition to use
+    # so we can remove the hard-coding of "AND" here
+    return queryset.filter(join_filter_with_condition(filters, "AND"))
+
+
+def filters_to_string(filters: FilterSet) -> str:
+    constructed_filters: list[dict[str, str | bool]] = []
+    for filter in filters:
+        constructed_filters.append(
+            {
+                "id": filter["filter"]["filter_id"],
+                "field": filter["filtered_field"],
+                "value": filter["filtered_value"],
+                "negated": filter.get("negated", False),
+            }
+        )
+    return json_dumps(constructed_filters)
+
+
+def string_to_filters(filter_string: str) -> FilterSet:
+    obj = json_loads(filter_string)
+    filters = [
+        {
+            "filter": defined_filters_list[item["id"]],
+            "filtered_field": item["field"],
+            "filtered_value": item["value"],
+            "negated": item.get("negated", False),
+        }
+        for item in obj
+    ]
+    if not is_filterset(filters):
+        raise ValueError("filters is not of type FilterSet")
+    return filters
+
+
 @login_required
 def list_sessions(request: HttpRequest) -> HttpResponse:
     context: dict[Any, Any] = {}
     page_number = request.GET.get("page", 1)
     limit = request.GET.get("limit", 10)
+    filters = request.GET.get("filters", "")
     sessions = Session.objects.order_by("-timestamp_start")
+    if filters != "":
+        filter_obj = string_to_filters(filters)
+        sessions = apply_filters(filter_obj, queryset=sessions)
     page_obj = None
     if int(limit) != 0:
         paginator = Paginator(sessions, limit)
@@ -45,6 +323,7 @@ def list_sessions(request: HttpRequest) -> HttpResponse:
             else None
         ),
         "data": {
+            "header_action": A([], Button([], "Add session"), url="add_session"),
             "columns": [
                 "Name",
                 "Date",
@@ -57,16 +336,11 @@ def list_sessions(request: HttpRequest) -> HttpResponse:
             "rows": [
                 [
                     A(
-                        [
-                            (
-                                "href",
-                                reverse(
+                        children=truncate_with_popover(session.purchase.edition.name),
+                        url=reverse(
                             "view_game",
                             args=[session.purchase.edition.game.pk],
                         ),
-                            )
-                        ],
-                        truncate_with_popover(session.purchase.edition.name),
                     ),
                     f"{session.timestamp_start.strftime(datetimeformat)}{f" — {session.timestamp_end.strftime(timeformat)}" if session.timestamp_end else ""}",
                     (