feat: 独立词库、三向认词与当日快闪复习

## 独立词库

理解词原先只能跟着课程单元走,学完 A0 十课词汇量只增加约 22 个实词,
不足以解决"记不住单词"。新增一份独立词库 assets/words/wordbank.json
(2748 词,A1–B1),挂进 receptiveWordRegistry 的合成单元 bank-A1/A2/B1,
完全复用理解词已有的状态机,不依赖课程进度,第一天就能用。

数据来源、许可与合成规则记在 tool/words/DATA-NOTE.md:CEFR-J 定等级、
公开词书提供音标、AI 重写全部释义并生成例句、OpenSubtitles 提供口语词频。
词书部分为 CC BY-NC-SA 4.0 且上游权利不明,仅供个人非商用;
若要分发或上架,须替换音标那一列。

## 背单词机制

- 间隔阶梯 1/3/7/15/30/60/120 天,连续答对上一级,答错回第一级。
  原先首次答对后要等 7 天才复习,正是"第二天就忘"的成因。
- 每日新词上限(10 分钟 8 个 / 20 分钟 15 个 / 30 分钟 20 个)。
  阶梯第一级是次日,今天引入的新词就是明天的工作量。
- 新词按口语频率发放,不再按字母序 —— A1 从 a.m./ability 变成 no/not/know/just。
- 三个方向按层级轮转:看词(英→中)→ 听词(音→中)→ 想词(中→英)。
  想词题仍是选择题,不要求产出,理解词定位不变,不进升级分母。
- 单词页独立成 tab,首页今日任务卡下方给一张认词入口卡。

## 用法对照

课程 JSON 增加 usage 字段(when/reply/swap/confuse):一个句型用在什么场合、
对方通常怎么答、还能怎么说、跟哪个学过的句型容易混。
知道 How are you? 的意思,不等于知道它不是用来问名字的。

## 复习流

- 当日快闪(recap)独立成队列,不占复习预算,也不计入积压。
- 只发放当日预算内的量,其余保持到期状态等下次,不悄悄丢弃或改期。
- 答错的项隔几题后回来,而不是立刻重问。

测试 296 通过,flutter analyze 干净。

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
This commit is contained in:
shenlei
2026-09-20 23:54:17 +09:00
co-authored by Claude Opus 5
parent 1a10ca88e0
commit 6b42b7abc3
52 changed files with 4044 additions and 82 deletions
@@ -0,0 +1,363 @@
import 'package:flutter/material.dart';
import '../../core/app_state.dart';
import '../../core/app_theme.dart';
import '../../core/courses/courses.dart';
import '../../core/models.dart';
import '../../core/voice_service.dart';
import '../../widgets/app_widgets.dart';
/// What the round of recognition is about right now. The home card and this
/// page share it so the two never describe today's words differently.
String wordTaskHeadline(AppState state) {
final due = state.dueWords.length;
if (due > 0) return '今天有 $due 个词该过一遍';
final unasked = state.unaskedWords.length;
if (unasked > 0) return '有 $unasked 个新学的词还没问过';
return '今天还能学 ${state.newWordQuota} 个新词';
}
/// The word list the learner can open on its own (learning engine 3.5).
///
/// Words are never asked to be produced here: the only task is a 5–10 second
/// recognition question, and the rest of the page is just what has been met.
class WordsPage extends StatefulWidget {
const WordsPage({super.key, required this.state});
final AppState state;
@override
State<WordsPage> createState() => _WordsPageState();
}
class _WordsPageState extends State<WordsPage> {
List<WordQuestion>? quiz;
int index = 0;
String? picked;
int right = 0;
void _startQuiz() {
final plan = widget.state.wordSession();
if (plan.isEmpty) return;
setState(() {
quiz = plan;
index = 0;
picked = null;
right = 0;
});
_playIfHeard(plan.first);
}
/// A listening question plays itself: the learner should not have to find a
/// button before the question has even been asked.
void _playIfHeard(WordQuestion question) {
if (question.mode != WordAskMode.listen) return;
VoiceService.instance.speak(wordEnglish(question.id));
}
void _answer(WordQuestion question, String option) {
final correct = option == question.answer;
widget.state.recordWordRecognition(question.id, correct: correct);
setState(() {
picked = option;
if (correct) right += 1;
});
}
void _next() {
final last = index + 1 >= quiz!.length;
setState(() {
if (last) {
quiz = null;
} else {
index += 1;
}
picked = null;
});
if (!last) _playIfHeard(quiz![index]);
}
@override
Widget build(BuildContext context) {
if (quiz case final questions?) return _quizView(questions[index]);
return _listView();
}
Widget _quizView(WordQuestion question) {
final answered = picked != null;
final english = wordEnglish(question.id);
final ipa = wordIpa(question.id);
// Before the answer each way round gives a different clue; after it all
// three land on the spelling, which is what the question was for.
// Withholding it earlier is the question: a heard word shown spelled is
// a reading question, and a meaning shown next to its word is no question
// at all.
final prompt = switch (question.mode) {
WordAskMode.read => english,
WordAskMode.listen => answered ? english : '· · ·',
WordAskMode.recall => answered ? english : question.shown,
};
// Speaking the word before a recall answer would just read it out.
final canSpeak = answered || question.mode != WordAskMode.recall;
return AppPage(
child: SpacedColumn(
children: [
Eyebrow(
'${switch (question.mode) {
WordAskMode.read => '认词',
WordAskMode.listen => '听词',
WordAskMode.recall => '想词',
}} · ${index + 1} / ${quiz!.length}',
),
Row(
children: [
Expanded(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
prompt,
style: Theme.of(context).textTheme.headlineMedium,
),
if (answered &&
ipa.isNotEmpty &&
question.mode != WordAskMode.read)
Text(ipa, style: Theme.of(context).textTheme.bodyMedium),
],
),
),
if (canSpeak)
IconButton(
icon: Icon(
question.mode == WordAskMode.listen
? Icons.replay_outlined
: Icons.volume_up_outlined,
),
tooltip: question.mode == WordAskMode.listen ? '再听一遍' : null,
onPressed: () => VoiceService.instance.speak(english),
),
],
),
Text(switch (question.mode) {
WordAskMode.read => '它是什么意思?只要认出来就行,不用会说。',
WordAskMode.listen => '听到的是哪个意思?听不清可以再听一遍。',
WordAskMode.recall => '哪个词是这个意思?认出来就行,不用自己拼。',
}),
for (final option in question.options)
SizedBox(
width: double.infinity,
child: OutlinedButton(
onPressed: answered ? null : () => _answer(question, option),
style: !answered || option != question.answer
? null
: OutlinedButton.styleFrom(
backgroundColor: AppColors.softGreen,
),
child: Align(
alignment: Alignment.centerLeft,
child: Padding(
padding: const EdgeInsets.symmetric(vertical: 6),
child: Text(option, style: const TextStyle(fontSize: 16)),
),
),
),
),
if (answered) ...[
SectionCard(
tint: picked == question.answer
? AppColors.softGreen
: AppColors.warm,
child: SpacedColumn(
children: [
Text(
picked == question.answer
? '对了。'
: question.mode == WordAskMode.recall
? '「${question.shown}」是 $english,明天再问你一次。'
: '$english 是「${question.answer}」,明天再问你一次。',
style: TextStyle(color: AppColors.warmInk, height: 1.45),
),
// The sentence is the point of the feedback: a gloss alone is
// what did not stick the first time.
if (WordBank.instance.exampleOf(question.id) case final sample?) ...[
Text(
sample.en,
style: TextStyle(
color: AppColors.warmInk,
fontSize: 16,
height: 1.45,
),
),
if (sample.zh.isNotEmpty)
Text(
sample.zh,
style: Theme.of(context).textTheme.bodyMedium,
),
],
if (WordBank.instance.moreSenses(question.id) case final more
when more.isNotEmpty)
Text(
'也有「$more」的意思。',
style: Theme.of(context).textTheme.bodySmall,
),
],
),
),
PrimaryButton(
label: index + 1 >= quiz!.length ? '做完了' : '下一个',
onPressed: _next,
),
],
TextButton(
onPressed: () => setState(() {
quiz = null;
picked = null;
}),
child: const Text('先不做了'),
),
],
),
);
}
Widget _listView() {
final state = widget.state;
final shaky = state.shakyWords;
final grouped = state.wordsByUnit;
final waiting = state.unstartedBankWordCount;
final quota = state.newWordQuota;
final planned = state.wordSessionPreviewSize;
return AppPage(
child: SpacedColumn(
children: [
const Eyebrow('学过的词'),
Text(
grouped.isEmpty
? '还没有学过的词'
: '认识 ${state.recognizedWordCount} · 熟悉 ${state.familiarWordCount}',
style: Theme.of(context).textTheme.headlineMedium,
),
const Text('这些词只要听到、看到能认出来就够了,不用背着写出来。'),
if (planned > 0)
SectionCard(
tint: AppColors.softGreen,
child: SpacedColumn(
children: [
Text(
wordTaskHeadline(state),
style: const TextStyle(fontSize: 17),
),
Text(
'$planned 个题,一个题几秒钟。',
style: Theme.of(context).textTheme.bodyMedium,
),
PrimaryButton(label: '开始认词', onPressed: _startQuiz),
],
),
)
else if (grouped.isNotEmpty)
SectionCard(
tint: AppColors.surfaceMuted,
child: Text(
quota > 0
? '今天的词都过完了,剩下的等到期再问。'
: '今天的新词学满 ${state.newWordsPerDay} 个了,到期的也都过完了。'
'明天它们会回来找你。',
),
),
if (waiting > 0)
Text(
quota > 0
? '词库里还有 $waiting 个词没开始,今天还能学 $quota 个。'
: '词库里还有 $waiting 个词没开始,明天继续。',
style: Theme.of(context).textTheme.bodySmall,
),
if (shaky.isNotEmpty) ...[
const Eyebrow('没记住的'),
SectionCard(
tint: AppColors.warm,
child: SpacedColumn(
children: [
for (final id in shaky.take(8)) _WordRow(id: id, state: state),
],
),
),
],
for (final entry in grouped.entries) ...[
Eyebrow(_unitTitle(entry.key)),
SectionCard(
tint: AppColors.surfaceMuted,
child: SpacedColumn(
children: [
for (final id in entry.value.take(_groupLimit))
_WordRow(id: id, state: state),
if (entry.value.length > _groupLimit)
Text(
'还有 ${entry.value.length - _groupLimit} 个',
style: Theme.of(context).textTheme.bodySmall,
),
],
),
),
],
],
),
);
}
/// A unit group is a reminder of what has been met, not a dictionary, so it
/// stops before the bank turns it into an endless scroll.
static const _groupLimit = 30;
String _unitTitle(String unit) {
if (unit.isEmpty) return '查词收藏';
if (WordBank.isBankUnit(unit)) return '词库 · ${WordBank.levelOfUnit(unit)}';
final lesson = allLessons.where((item) => item.id == unit);
return lesson.isEmpty ? unit : lesson.first.title;
}
}
class _WordRow extends StatelessWidget {
const _WordRow({required this.id, required this.state});
final String id;
final AppState state;
@override
Widget build(BuildContext context) {
final status = state.wordStatus(id);
return Row(
children: [
Expanded(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Text(
wordEnglish(id),
style: const TextStyle(fontSize: 16, fontWeight: FontWeight.w600),
),
Text(
wordIpa(id).isEmpty
? wordMeaning(id)
: '${wordIpa(id)} ${wordMeaning(id)}',
style: Theme.of(context).textTheme.bodyMedium,
),
],
),
),
Text(
switch (status) {
WordStatus.newWord => '新学',
WordStatus.recognized => '认识',
WordStatus.familiar => '熟悉',
},
style: Theme.of(context).textTheme.bodySmall,
),
IconButton(
icon: const Icon(Icons.volume_up_outlined, size: 20),
onPressed: () => VoiceService.instance.speak(wordEnglish(id)),
),
],
);
}
}