From 0520120ccfd39b5e4539ae360b97923abfa3a586 Mon Sep 17 00:00:00 2001
From: daniel-michel <65034538+daniel-michel@users.noreply.github.com>
Date: Wed, 10 Jan 2024 14:46:03 +0100
Subject: [PATCH] feature: movie description

---
 lib/api/wikidata_movie_api.dart | 57 ++++++++++++++++++++++++++++++++-
 lib/model/movie.dart            | 12 +++++++
 lib/view/movie_page.dart        |  3 +-
 3 files changed, 70 insertions(+), 2 deletions(-)

diff --git a/lib/api/wikidata_movie_api.dart b/lib/api/wikidata_movie_api.dart
index 13ebf1b..2364144 100644
--- a/lib/api/wikidata_movie_api.dart
+++ b/lib/api/wikidata_movie_api.dart
@@ -75,7 +75,7 @@ class WikidataMovieApi implements MovieApi {
       final start = i * batchSize;
       final end = min((i + 1) * batchSize, movieIds.length);
       var response = await _wikidataApi.get(
-          "&action=wbgetentities&format=json&props=labels|claims&ids=${movieIds.sublist(start, end).join("|")}");
+          "&action=wbgetentities&format=json&props=labels|claims|sitelinks/urls&ids=${movieIds.sublist(start, end).join("|")}");
       Map<String, dynamic> result = jsonDecode(response.body);
       Map<String, dynamic> batchEntities = result["entities"];
       entities.addAll(batchEntities);
@@ -94,6 +94,12 @@ class WikidataMovieApi implements MovieApi {
     // they will be retrieved from the cache in fromWikidataEntity
     await _getLabelsForEntities(allCountryAndGenreIds);
 
+    // Get wikipedia explaintexts
+    Iterable<String> allWikipediaTitles =
+        selectInJson<String>(entities, "*.sitelinks.enwiki.url")
+            .map((url) => url.split("/").last);
+    await _getWikipediaExplainTextForTitles(allWikipediaTitles.toList());
+
     return movieIds
         .map((id) => WikidataMovieData.fromWikidataEntity(id, entities[id]))
         .toList();
@@ -142,6 +148,13 @@ class WikidataMovieData extends MovieData {
     String title =
         selectInJson<String>(entity, "labels.en.value").firstOrNull ??
             selectInJson<String>(entity, "labels.*.value").first;
+    String? wikipediaTitle = selectInJson(entity, "sitelinks.enwiki.url")
+        .firstOrNull
+        ?.split("/")
+        .last;
+    String? description = wikipediaTitle != null
+        ? _getCachedWikipediaExplainTextFotTitle(wikipediaTitle)
+        : null;
     Map<String, dynamic> claims = entity["claims"];
     List<TitleInLanguage>? titles = selectInJson(
             claims, "${WikidataProperties.title}.*.mainsnak.datavalue.value")
@@ -167,6 +180,7 @@ class WikidataMovieData extends MovieData {
                 DateTime.now(), DatePrecision.decade, "unknown location"),
         entityId);
     movie.setDetails(
+      description: description,
       titles: titles,
       releaseDates: releaseDates,
       genres: genres,
@@ -267,3 +281,44 @@ Future<Map<String, String>> _getLabelsForEntities(
 String _getCachedLabelForEntity(String entityId) {
   return _labelCache[entityId] ?? entityId;
 }
+
+ApiManager _wikipediaApi =
+    ApiManager("https://en.wikipedia.org/w/api.php?format=json&origin=*");
+Map<String, String> _wikipediaExplainTextCache = {};
+Future<Map<String, String>> _getWikipediaExplainTextForTitles(
+    List<String> pageTitles) async {
+  const batchSize = 50;
+  Map<String, String> explainTexts = {};
+  for (int i = pageTitles.length - 1; i >= 0; i--) {
+    if (_labelCache.containsKey(pageTitles[i])) {
+      explainTexts[pageTitles[i]] = _labelCache[pageTitles[i]]!;
+      pageTitles.removeAt(i);
+    }
+  }
+  for (int i = 0; i < (pageTitles.length / batchSize).ceil(); i++) {
+    final start = i * batchSize;
+    final end = min((i + 1) * batchSize, pageTitles.length);
+    Response response = await _wikipediaApi.get(
+        "&action=query&prop=extracts&exintro&explaintext&redirects=1&titles=${pageTitles.sublist(start, end).join("|")}");
+    Map<String, dynamic> result = jsonDecode(response.body);
+    List<dynamic> normalize = result["query"]["normalized"];
+    Map<String, dynamic> batchPages = result["query"]["pages"];
+    for (String pageId in batchPages.keys) {
+      String pageTitle = batchPages[pageId]["title"];
+      String originalTitle = normalize
+              .where((element) => element["to"] == pageTitle)
+              .firstOrNull?["from"] ??
+          pageTitle;
+      String? explainText = batchPages[pageId]["extract"];
+      if (explainText != null) {
+        _wikipediaExplainTextCache[originalTitle] =
+            explainTexts[originalTitle] = explainText;
+      }
+    }
+  }
+  return explainTexts;
+}
+
+String? _getCachedWikipediaExplainTextFotTitle(String title) {
+  return _wikipediaExplainTextCache[title];
+}
diff --git a/lib/model/movie.dart b/lib/model/movie.dart
index e386299..57d518c 100644
--- a/lib/model/movie.dart
+++ b/lib/model/movie.dart
@@ -7,6 +7,7 @@ class MovieData extends ChangeNotifier {
   bool _bookmarked = false;
 
   bool _hasDetails = false;
+  String? _description;
   List<DateWithPrecisionAndCountry>? _releaseDates;
   List<String>? _genres;
   List<TitleInLanguage>? _titles;
@@ -25,6 +26,10 @@ class MovieData extends ChangeNotifier {
     return _bookmarked;
   }
 
+  get description {
+    return _description;
+  }
+
   List<DateWithPrecisionAndCountry>? get releaseDates {
     return _releaseDates;
   }
@@ -47,6 +52,7 @@ class MovieData extends ChangeNotifier {
     setDetails(
         title: movie.title,
         releaseDate: movie.releaseDate,
+        description: movie.description,
         releaseDates: movie.releaseDates,
         genres: movie.genres,
         titles: movie.titles);
@@ -56,6 +62,7 @@ class MovieData extends ChangeNotifier {
       {String? title,
       DateWithPrecisionAndCountry? releaseDate,
       bool? bookmarked,
+      String? description,
       List<DateWithPrecisionAndCountry>? releaseDates,
       List<String>? genres,
       List<TitleInLanguage>? titles}) {
@@ -68,6 +75,9 @@ class MovieData extends ChangeNotifier {
     if (bookmarked != null) {
       _bookmarked = bookmarked;
     }
+    if (description != null) {
+      _description = description;
+    }
     if (releaseDates != null) {
       _releaseDates = releaseDates;
     }
@@ -99,6 +109,7 @@ class MovieData extends ChangeNotifier {
       "title": title,
       "releaseDate": _releaseDate.toJsonEncodable(),
       "bookmarked": _bookmarked,
+      "description": _description,
       "releaseDates": releaseDatesByCountry,
       "genres": genres,
       "titles": titlesByCountry,
@@ -111,6 +122,7 @@ class MovieData extends ChangeNotifier {
             DateWithPrecisionAndCountry.fromJsonEncodable(json["releaseDate"]) {
     setDetails(
         bookmarked: json["bookmarked"] as bool,
+        description: json["description"] as String?,
         genres: (json["genres"] as List<dynamic>?)
             ?.map((genre) => genre as String)
             .toList(),
diff --git a/lib/view/movie_page.dart b/lib/view/movie_page.dart
index fe9d31e..2b764e2 100644
--- a/lib/view/movie_page.dart
+++ b/lib/view/movie_page.dart
@@ -51,7 +51,8 @@ class MoviePage extends StatelessWidget {
                             .toList() ??
                         [],
                   ),
-                  const SizedBox(height: 20),
+                  const Heading("Description"),
+                  Text(movie.description ?? "No description"),
                   const Heading("Titles"),
                   Table(
                     border: TableBorder.symmetric(