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Changelog

Release History

In-Interface CSV Error Resolution & Production Hardening (v1.8.0)

Latest Production Release • In-App Question Rescue & Reliability Architecture

Latest Release

A major usability and reliability milestone. Rather than discarding rows or halting CSV imports when options are missing or columns are misaligned, StudyOS v1.8.0 brings In-Interface Error Resolution. Students can review malformed rows in real time, 1-tap convert them to short answers, or repair options and answers directly on-screen with tactile chips. Coupled with 5 deep system-hardening improvements across App Blocker, PDF pagination, database write atomicity, spaced repetition calendar scheduling, and audio walk focus hygiene.

📐 Architectural Logic & In-Interface Issue Resolution Flow

In traditional educational software, CSV imports are brittle: one missing column or unexpected quote aborts the entire file, forcing the student out to an external spreadsheet. In StudyOS v1.8.0, the pipeline never loses data:

1. Stem Option Extraction

When options are embedded inside question stems (e.g., (A) ... (B) ...), the engine extracts them automatically into individual options without error.

2. Interactive Error Cards

Malformed rows are preserved in activeErrors and rendered as interactive cards inside the import modal with row number, error diagnosis, and prompt snippet.

3. 1-Tap & Bulk Rescue

⚡ Convert to Short (and ⚡ Convert All) instantly rescues questions missing options, converting them to standard Short Answer format with zero typing.

4. In-App Option Editor

✏️ Fix Options launches FixQuestionRowDialog: type Option A/B/C/D and tap [A], [B], [C], or [D] chips to validate and rescue on-device.

👁️ Visual Blueprint: How Rescued Questions & Error Cards Look

1. Interactive Issue Resolution Card (In-Dialog)

⚠️ Row 4: MCQ requires at least OptionA and OptionB ✕ Skip

"Which vector quantity represents the rate of change of angular momentum?"

⚡ Convert to Short

✏️ Fix Options

2. Multiple Choice Question (MCQ) Card Layout

MCQ ● Easy 🎯 2x tested

★ 1 Mark

Which particle is the primary carrier of electric current in metallic conductors?

A Protons

B Free Electrons

✓ Correct

C Neutrons

D Positrons

💡 Solution Key & Rationale

In metallic conductors, valence electrons are delocalized and drift under an applied electric field.

FILL IN THE BLANK (FIB)

The light-absorbing green pigment found inside chloroplasts is called [ ________ ].

Target: Chlorophyll

TRUE / FALSE

An exothermic reaction absorbs thermal energy from its surroundings.

TRUE ✓ FALSE (Correct)

🛡️ 5 Subsystem Production Hardening Upgrades

App Blocker Resilience & Instant Kickout: Added cold boot and onServiceConnected() preference sync, 1000ms debounce per package, and immediate performGlobalAction(GLOBAL_ACTION_HOME) dispatch before launching the lock screen.
Intra-Question PDF Continuation Pagination: Generates multi-page exams with line-by-line bounds checking, — Q<Num> (Continued) — headers, and unbreakable formula character-level word wrapping.
Room Database Transaction Atomicity: Wrapped all multi-table insertions across QuizRepositoryImpl, QuestionPaperGenerator, and UniversalCsvProcessor in database.withTransaction with 250-row batch chunking.
Spaced Repetition 04:00 AM Alignment: Next review timestamps align deterministically to 04:00 AM on the target calendar day, eliminating time-of-day creep.
Feynman Audio Walk Focus Hygiene: Releases audio focus immediately upon speech recognition error and composable disposal.

Objective Question Bank & Dynamic Formation Engine (v1.7.0)

Prior Production Release • Complete Feature Planning, Design & Logic

v1.7.0

A major architectural leap introducing the Universal Objective CSV Engine, deterministic Question Formation Normalization, and interactive Live Question Previews. Import hundreds of Multiple Choice Questions (MCQs), Fill in the Blanks (FIBs), and True/False questions in seconds with zero data loss and automated syntax repair.

📐 Feature Planning & Architectural Logic

Standard question banks frequently struggle when importing CSVs due to Excel UTF-8 BOM byte order marks (\uFEFF), embedded multi-line cells containing line breaks inside quotes, inconsistent delimiter conventions (semicolons, commas, tabs), and accidental question numbering or option prefixes. The v1.7.0 engine implements a multi-stage offline pipeline:

1. Ingestion & BOM Stripping

Strips UTF-8 BOM headers (\uFEFF, \uEFBBBF) and auto-detects delimiters (, vs ; vs \t).

2. RFC-4180 State Machine

Character-by-character tokenizer perfectly preserves line breaks inside multi-line quoted questions and explanations.

3. Question Formation Logic

Strips redundant prefixes (Q1., A)) and separates explanations from correct answers (splitAnswerAndExplanation).

4. Dual Room Routing & Resiliency

Non-blocking partial imports populate question_bank and flashcards; invalid rows are skipped without halting valid items.

👁️ Visual Blueprint: How Each Question Looks

1. Multiple Choice Question (MCQ) Card Layout

MCQ ● Easy 🎯 2x tested

★ 1 Mark

Which particle is the primary carrier of electric current in metallic conductors?

A Protons

B Free Electrons

✓ Correct

C Neutrons

D Positrons

💡 Solution Key & Rationale

In metallic conductors, valence electrons are delocalized and drift under an applied electric field.

2. Fill-in-the-Blank (FIB) Card Layout

FILL BLANK ★ 1 Mark

The light-absorbing green pigment found inside chloroplasts is called [ ________ ].

🎯 Target Blank Answer: [ Chlorophyll ]

3. True / False Card Layout

TRUE / FALSE ★ 1 Mark

An exothermic reaction absorbs thermal energy from its surroundings.

TRUE

✓ FALSE (Correct)

📋 CSV Import Blueprint & Column Specifications

Column Name	Accepted Aliases	Required?	Default Fallback	Purpose & Description
SubjectName	subject, sub, course	Optional	"General"	Course or subject category hierarchy
ChapterName	chapter, chap, unit, module	Optional	"General Practice"	Chapter grouping for practice hub
QuestionType	type, qtype, category	Optional	Auto-detected	MCQ, FIB, TRUE_FALSE, or SHORT_ANSWER
Question	questiontext, prompt, stem, q	Mandatory	—	The core question prompt or sentence
OptionA..D	opta..d, a..d, choicea..d	Conditional	Blank	MCQ options (OptionA & B required for MCQ)
CorrectAnswer	answer, key, correct, ans	Mandatory	—	Matching option letter, boolean, or exact text
Explanation	solution, markingscheme, rationale	Optional	Blank	Pedagogical step-by-step reasoning
Difficulty / Marks	diff, level, marks, score	Optional	"MEDIUM" / 1	EASY \| MEDIUM \| HARD; Marks weight

Universal CSV Auto-Detection: Auto-detects whether the user is pasting Objective questions (MCQs, FIBs, True/False) or Standard numerical/theory questions with seamless 3-way toggle.
Live In-Dialog Preview: Immediate real-time rendering of the first recognized question card inside the modal before committing the import.
Non-Blocking Isolation: Isolated syntax mistakes in specific rows are gracefully reported while all valid rows are instantly imported into Room SQLite.
Phase 1–5 Hardened Security & Data Safeguards: Fully enforced network security cleartext prohibitions, pre-migration database snapshotting, and air-gapped AES-256-GCM backup integrity verification.
133 Unit Tests Passing: Comprehensive unit test suite covering BOM removal, delimiter auto-detection, multi-line quoted fields, fuzzy header normalization, and question cleaning logic.

Objective Questions CSV Engine (v1.6.0)

Prior Release Build

v1.6.0

Universal CSV Objective Questions Import: Dedicated engine to import MCQs (Multiple Choice Questions with A/B/C/D option tiles), Fill in the Blanks (FIB with interactive sentence preview), and True/False questions directly from CSV with auto-repair and dual Room persistence (question_bank + flashcards).
Interactive Quiz Runner Overhaul: Sleek letter pills (A)-(D) with accent glow, tactile dual [✓ True] / [✗ False] tiles, and dynamic real-time typing into sentence blanks.
Smart Fuzzy Answer Verification: Natural answer grading ignoring leading articles, punctuation differences, and supporting slash-separated synonyms.
Question Bank Card & UI Polish: Segmented Objective / Standard format toggle, 1-tap CSV template sharing, difficulty badges, and clean multi-line PDF exam paper rendering.
Robust Test Suite: 129 comprehensive unit tests verifying zero regressions across CSV, quiz engines, Room queries, and view models.

Calm Serenity & Knowledge Graph Release (v1.4.0)

Stable Production Build

v1.4.0

Bidirectional Note Linking & Knowledge Graph: Interconnect your concepts using [[WikiLinks]] syntax with real-time clickable navigation and a 2D interactive force-directed graph visualizer.
Hands-Free Audio Flashcard Drill: Eyes-free spaced repetition study using local Android Text-to-Speech loop (Reads Question → pause for retrieval → speaks Answer → auto-advances).
AI Exam Readiness Radar & Weak Spot Diagnoser: Mathematical 5-axis cognitive readiness spider chart with 1-tap automated 10-minute micro-sprint recommendations.
Air-Gapped AES-256-GCM Encrypted Backups: Export and restore your complete database with military-grade PBKDF2 (10,000 iterations) + AES-256-GCM encryption with 0 cloud leakage.
Foreground FocusService Hardening: Background study sessions with persistent foreground status, 60-second SQLite checkpoints, and crash recovery.
Streaming Document Extraction & Bitmap Recycling: Bounded 16MB stream buffers and RGB_565 downsampling to prevent Dalvik OOM on large scanned PDFs.
Self-Healing Room Integrity Engine: Automatic database quick checks, foreign key verification, WAL checkpointing, and index rebuilds.
Focus Timer Home Screen AppWidget: Quick glance remaining time and start/pause controls right from the Android launcher.
Hardware Keyboard Shortcuts: Full tablet and Chromebook support (Ctrl+N, Ctrl+Space, Space, and Arrow keys).
Minimalist "Coffee Time" Aesthetic: Soft, serene colors (Obsidian `#101216`, Amber Latte `#D4A373`, Soft Chamomile `#EAD9B8`, Muted Sage `#CCD5AE`).

Google Docs & Drive Document Previewer (v1.3.1)

Document Viewing & TTS Narration

v1.3.1

Native Document Viewer: View PDF, Word (.docx, .doc), Markdown (.md), and Text (.txt) files in authentic Google Docs & Drive style paper canvas layout.
Visual High-DPI PDF Rendering: Native Android PdfRenderer converts PDF pages into sharp zoomable bitmaps with page navigation and thumbnail jumping.
Find in Document (Ctrl+F): Real-time text search highlighting matches and cycling previous/next occurrences with exact match counters.
Eye-Friendly Themes & Typography: Google Docs White, Sepia Warm, Midnight Dark, and Slate Cool themes with dynamic text scaling (12sp–24sp).
Text-to-Speech (TTS) Narration: Built-in audio player that reads aloud any document with play/pause, restart, and position tracking.
1-Click AI Transformations: Convert any document or note into StudyOS Notes, spaced-repetition Flashcards, or AI Practice Quizzes with one tap.

All-In-One Intelligence Release (v1.3.0)

UI Polish & Socratic Audio Walk

v1.3.0

Distraction-Free AI Study Session: 5-step cognitive flow (Learn → Recall → Practice → Evaluate → Complete) with local Room persistence.
Sidebar Study Countdown Timer: Circular animated clock, presets (25m, 45m, 60m, stopwatch), and native AlarmManager background alerts.
Dedicated Mock & Tuition Tests Column: Separate tab filter, subject selector, date, and exact native TimePickerDialog (HH:mm).
Mistake Bank & Taxonomy: 5-category cognitive error classification (Concept, Memory, Calculation, Misread, Careless) with diagnostic remediation.
Exam Readiness Engine: 7-dimension mathematical preparation index.
Smart Dynamic Revision Queue: Urgency priority sorting based on memory decay curves.
Subject Intelligence Badges: Real-time Strong / Weak / Due chapter breakdown.
Global Instant Offline Search: Sub-second query across subjects, notes, cards, and mistakes.

Core Foundation Release

Initial Offline Architecture Build

Foundation

Initial offline Room SQLite database architecture.
Subject and Chapter syllabus tracking.
Basic active recall flashcard system.
Jetpack Compose UI with dark surface design system.

Installing on Android (Step-by-Step)

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