# Changelog

All notable changes to this project will be documented in this file.

The format is based on [Keep a
Changelog](https://keepachangelog.com/en/1.1.0/), and this project adheres to
[Semantic Versioning](https://semver.org/spec/v2.0.0.html).

## [0.7.0] - 2026-04-22

### Added

- **`--dry-run` option**: Validate configuration and preview what would happen
  without making any LLM API calls. Useful for validating feeds file and
  configuration, checking article counts and filtering results and anything
  else that can be done "offline".
- **Styled terminal output using `lipgloss`**: All CLI output now uses ANSI
  colour codes for better readability:
- **`$NO_COLOR` environment variable support**: Respects the ["no
color"](https://no-color.org/) standard. When `NO_COLOR` is set, all styling is
disabled and plain text is output instead.

### Changed

- API key validation now only occurs when not using `--dry-run` mode

## [0.6.0] - 2026-04-22

### Added

- **Comprehensive unit test suite**, including CLI argument tests
  (`--feeds-file`, `--prompt`, `--api-key`, `--model`, `--base-url`),
  configuration tests, aggregator tests, output formatter tests, processor
  tests and defaults tests.
- **`--base-url` CLI option**: configure custom API endpoints for different LLM
  providers. Should support any OpenAI-compatible provider.
  - Environment variable: `LLM_AGGREGATOR_BASE_URL`
- `internal/defaults` package
- `docs/TESTING.md` which contains a comprehensive testing guide with test
  descriptions

### Changed

- **Configuration defaults**: All packages now use `defaults.Default*` constants
  - `internal/config`: Uses `defaults.Default*` for default values
  - `internal/runtime`: Uses `defaults.Default*` for runtime defaults
  - `internal/llm`: Uses `defaults.Default*` for LLM client defaults

### Fixed

- `nil` pointer safety in aggregator
  - Added nil checks for `progressCtx` across all log statements
  - `FeedAggregator` now works correctly when progress context is nil
  - Tests use `NewFeedAggregatorWithProgress` with explicit progress context

## [0.5.0] - 2026-04-22

### Added

- **Accurate token counting with tiktoken**
  - New `internal/tokeniser` package using OpenAI's tiktoken-go library
  - BPE tokenisation for accurate token counting vs rough character estimation
  - Encoding caching to avoid repeated initialisation overhead
  - Model-aware encoding selection (cl100k_base, o200k_base, etc.)
  - `CountTokens()` and `CountMessagesTokens()` functions
  - Fallback to rough estimation when tiktoken initialisation fails
- **Concurrent feed fetching**: Feeds are now fetched concurrently using
  `golang.org/x/sync/errgroup`
  - Semaphore limits concurrent requests to 10 to avoid server overload
  - Mutex-protected shared state for thread-safe article collection
  - Partial failures don't stop other feeds from being processed
- **Scrollable summary in TUI**
  - Bubble Tea viewport component for browsing long summaries
  - Keyboard navigation: j/k or arrows (scroll), Space/B (page), g/G
  (start/end)
  - Mouse wheel scrolling support
  - Scroll progress indicator showing position and total lines

### Changed

- **Streamlined configuration management**: Viper now uses global instance with
automatic precedence handling. Simplified configuration flow: Parse → GetViper
→ BindCLIArgs → ViperToRuntime
- **TUI colour scheme**: All hex colour codes replaced with ANSI 256-colour
  palette

### Fixed

- Viewport now properly handles scroll events via `Update()`. Summary content
  pre-wrapped to viewport width before display
- Fixed string literal colour names to use actual variables

## [0.4.0] - 2026-04-21

### Changed 

- **TUI is now fully functional and production-ready**: Replaced the
work-in-progress TUI implementation with a robust Bubble Tea command pattern:
  - Runtime execution now uses native `tea.Cmd` instead of manual goroutine
  orchestration.
  - Added real-time progress updates via `progress.Progress` interface with
  stage, substage, and article count messages.
  - TUI displays a spinner, elapsed time, and final summary inline.
  - Removed signal handling and channel synchronisation in favour of Bubble
  Tea's built-in lifecycle.
  - `TUIProgress` now only sends messages to an existing program, simplifying
  integration.
  - Both verbose mode (`SimpleLogger`) and TUI mode share the same
  `progress.Progress` interface.

## [0.3.0] - 2026-04-21

### Added

- **Configuration file support via TOML** (XDG-compliant and cross-platform)
  - Load settings from `~/.config/llm_aggregator/config.toml`
  - Supports all aggregation, API, and output options
  - Example configuration file at `configs/config.example.toml`
- **Environment variable support with `LLM_AGGREGATOR_` prefix**
  - All configuration options can be set via environment variables
  - Precedence order: CLI arguments > environment variables > config file >
  built‑in defaults
- New `internal/config` package with Viper integration
  - `Load()` and `Save()` methods for configuration management
  - `GetConfigPath()` for XDG‑compliant config file location
  - `ConfigExists()` to check for existing configuration
- Comprehensive unit tests for configuration loading, saving, and environment
  variable precedence (`internal/config/config_test.go`)

### Changed

- **Environment variable renamed:** `DEEPSEEK_API_KEY` →
  `LLM_AGGREGATOR_API_KEY`
- **CLI help text** now reflects the new API key environment variable and
  general configuration options
- **Command‑line argument precedence** implemented in `cmd/llm_aggregator.go`
via `applyConfiguration()`
- Updated all help text, documentation, and code references
- `README.md` completely revised with a new "Configuration" section

### Removed

- Global `QuietMode` and `VerboseMode` variables from
`internal/config/config.go`. Replaced by runtime‑specific configuration in
`runtime.Runtime` and CLI arguments
- Hardcoded system prompt in `runtime.NewRuntime()`. Now left empty, allowing
configuration or client default to be used
- CLI flags now correctly override config file and environment variables

## [0.2.0] - 2026-04-21

### Changed

- Moved all progress and status messages behind `-v/--verbose` flag
- Default CLI mode is now silent except for final output and errors
- Components (aggregator, processor, LLM client) use logger interface
controlled by verbose flag

## [0.1.0] - 2026-04-21

### Added

- Complete translation from Python prototype to Go implementation
- RSS/Atom feed parsing using `gofeed` library
- DeepSeek API integration via `openai-go` client, configured for `/chat/completions` endpoint
- Content filtering and processing with keyword‑based include/exclude, date filtering, and sorting
- Command‑line interface using `go‑arg` with automatic help and version flags
- Multiple output formats: plain text, GitHub‑flavoured markdown, and JSON
- Terminal user interface (TUI) built with `bubbletea` featuring:
  - Animated progress bar with gradient colours (`#FF7CCB` to `#FDFF8C`)
  - Live article counters (aggregated/processed)
  - Elapsed time display
  - Coloured status indicators using `lipgloss` styling
  - Keyboard controls (q/Ctrl+C to quit)
- Web content extraction fallback using `goquery` when feed descriptions are minimal
- Configurable limits: articles per feed, maximum age, total articles
- Token estimation and API usage logging
- Environment variable support (`LLM_AGGREGATOR_API_KEY`) for authentication
- Example feeds file with technology, programming, and free software sources

### Changed

- Program structure organised into standard Go layout: `cmd/`, `internal/`, `pkg/`
- English spelling conventions maintained throughout (colour, initialise, summarise)
- Error handling improved with specific messages for common API failures (invalid key, rate limits, etc.)
- Progress reporting unified through a `ProgressContext` interface for both TUI and CLI modes

### Fixed

- Initial API endpoint mismatch (using `/responses` instead of `/chat/completions`)
- Nil pointer dereferences when handling optional feed metadata (author, dates)
- String repetition syntax errors in Go (replaced `"="*80` with `strings.Repeat`)
- CLI help/version flag handling to show information without requiring other arguments
- Type compatibility issues with `openai-go` v3 API (message parameters, token usage fields)