yoloyolo/.planning/milestones/v1.1-phases/06-config-package-and-sound-overrides/06-02-PLAN.md

---
phase: 06-config-package-and-sound-overrides
plan: 02
type: execute
wave: 2
depends_on: ["06-01"]
files_modified:
  - encode/mp3.go
  - encode/mp3_test.go
  - cmd/netsynth/main.go
autonomous: true
requirements:
  - CFG-03

must_haves:
  truths:
    - "User passes --config /path/to/file.toml and the tool uses that file for sound overrides"
    - "User passes --config /nonexistent.toml and the tool exits with a clear error before capture"
    - "User runs without --config and auto-discovery kicks in (or defaults used silently)"
    - "RunSynthesis uses the merged config map instead of hardcoded ClassFreqConfigs"
  artifacts:
    - path: "cmd/netsynth/main.go"
      provides: "--config flag, config.Load call, passing merged map to RunSynthesis"
      contains: "configPath"
    - path: "encode/mp3.go"
      provides: "RunSynthesis with freqCfgs parameter"
      contains: "freqCfgs map[classify.TrafficClass]synth.FreqConfig"
    - path: "encode/mp3_test.go"
      provides: "Updated tests for new RunSynthesis signature"
  key_links:
    - from: "cmd/netsynth/main.go"
      to: "config/config.go"
      via: "config.Load(configPath)"
      pattern: "config\\.Load"
    - from: "cmd/netsynth/main.go"
      to: "encode/mp3.go"
      via: "encode.RunSynthesis(snapshots, outputPath, freqCfgs)"
      pattern: "encode\\.RunSynthesis.*freqCfgs"
    - from: "encode/mp3.go"
      to: "synth/bank.go"
      via: "synth.NewBank(1.0, freqCfgs) using passed-in config"
      pattern: "synth\\.NewBank.*freqCfgs"
---

<objective>
Wire the config package into the CLI and synthesis pipeline. Add `--config` flag to Cobra, call `config.Load` at startup, change `RunSynthesis` signature to accept the merged config map, and update all call sites.

Purpose: Completes CFG-03 (explicit --config flag) and D-10 (RunSynthesis signature change). After this plan, the end-to-end flow works: user creates TOML -> tool loads it -> synthesis uses overridden frequencies/waveforms.

Output: Updated `cmd/netsynth/main.go`, `encode/mp3.go`, `encode/mp3_test.go`
</objective>

<execution_context>
@$HOME/.claude/get-shit-done/workflows/execute-plan.md
@$HOME/.claude/get-shit-done/templates/summary.md
</execution_context>

<context>
@.planning/PROJECT.md
@.planning/ROADMAP.md
@.planning/STATE.md
@.planning/phases/06-config-package-and-sound-overrides/06-CONTEXT.md
@.planning/phases/06-config-package-and-sound-overrides/06-01-SUMMARY.md

<interfaces>
<!-- Key types and contracts the executor needs. -->

From config/config.go (created in Plan 01):
```go
// Load finds, parses, validates, and merges a config file.
// configPath is the --config flag value; empty string triggers auto-discovery.
func Load(configPath string) (map[classify.TrafficClass]synth.FreqConfig, error)
```

From encode/mp3.go (current signature to change):
```go
// Current:
func RunSynthesis(snapshots []classify.WindowSnapshot, outputPath string) error
// New:
func RunSynthesis(snapshots []classify.WindowSnapshot, outputPath string, freqCfgs map[classify.TrafficClass]synth.FreqConfig) error
```

From cmd/netsynth/main.go (existing flags pattern):
```go
var (
    ifaceName  string
    listIfaces bool
    verbose    bool
    outputPath string
    bpfFilter  string
    readPath   string
)
// Flag registration pattern:
rootCmd.Flags().StringVar(&bpfFilter, "filter", "", "BPF filter expression")
```

From synth/config.go:
```go
var ClassFreqConfigs = map[classify.TrafficClass]FreqConfig{ /* 14 entries */ }
```
</interfaces>
</context>

<tasks>

<task type="auto">
  <name>Task 1: Change RunSynthesis signature and update encode tests</name>
  <files>encode/mp3.go, encode/mp3_test.go</files>
  <read_first>
    encode/mp3.go (current RunSynthesis signature and body)
    encode/mp3_test.go (current test calls to RunSynthesis)
    synth/config.go (ClassFreqConfigs, FreqConfig type)
    classify/types.go (TrafficClass type)
  </read_first>
  <action>
    **encode/mp3.go changes:**

    1. Add `freqCfgs map[classify.TrafficClass]synth.FreqConfig` as third parameter to RunSynthesis:
       ```
       func RunSynthesis(snapshots []classify.WindowSnapshot, outputPath string, freqCfgs map[classify.TrafficClass]synth.FreqConfig) error
       ```

    2. Change line 57 from:
       ```
       bank := synth.NewBank(1.0, synth.ClassFreqConfigs)
       ```
       to:
       ```
       bank := synth.NewBank(1.0, freqCfgs)
       ```

    3. No other changes to encode/mp3.go.

    **encode/mp3_test.go changes:**

    4. Update `TestMP3Valid` (line 56): change `RunSynthesis(snaps, tmpPath)` to `RunSynthesis(snaps, tmpPath, synth.ClassFreqConfigs)`.

    5. Update `TestZeroPacketError` (line 101): change `RunSynthesis([]classify.WindowSnapshot{}, tmpPath)` to `RunSynthesis([]classify.WindowSnapshot{}, tmpPath, synth.ClassFreqConfigs)`.

    6. Update `TestZeroPacketError` (line 121): change `RunSynthesis(zeroSnaps, tmpPath2)` to `RunSynthesis(zeroSnaps, tmpPath2, synth.ClassFreqConfigs)`.

    The `synth` import is already present in mp3_test.go.
  </action>
  <verify>
    <automated>cd /home/dev/workspace/yoloyolo && go build ./encode/... && go test ./encode/... -count=1 -run TestZeroPacketError</automated>
  </verify>
  <acceptance_criteria>
    - encode/mp3.go contains `func RunSynthesis(snapshots []classify.WindowSnapshot, outputPath string, freqCfgs map[classify.TrafficClass]synth.FreqConfig) error`
    - encode/mp3.go contains `synth.NewBank(1.0, freqCfgs)` (not synth.ClassFreqConfigs)
    - encode/mp3_test.go contains `RunSynthesis(snaps, tmpPath, synth.ClassFreqConfigs)`
    - encode/mp3_test.go contains `RunSynthesis([]classify.WindowSnapshot{}, tmpPath, synth.ClassFreqConfigs)`
    - encode/mp3_test.go contains `RunSynthesis(zeroSnaps, tmpPath2, synth.ClassFreqConfigs)`
    - `go build ./encode/...` exits 0
    - `go test ./encode/... -count=1 -run TestZeroPacketError` exits 0
  </acceptance_criteria>
  <done>
    RunSynthesis accepts injected config map. All encode tests updated and passing.
  </done>
</task>

<task type="auto">
  <name>Task 2: Add --config flag and wire config.Load into main.go</name>
  <files>cmd/netsynth/main.go</files>
  <read_first>
    cmd/netsynth/main.go (full file — flag definitions, run function, runLiveMode, runPcapMode)
    config/config.go (Load function signature)
    encode/mp3.go (updated RunSynthesis signature from Task 1)
  </read_first>
  <action>
    **cmd/netsynth/main.go changes:**

    1. Add `configPath` to the var block (after `readPath`):
       ```go
       configPath string // NEW: --config flag (CFG-03)
       ```

    2. Add import for config package in the import block:
       ```go
       "github.com/netsynth/netsynth/config"
       ```
       Also add import for `synth` package (needed for ClassFreqConfigs fallback reference — though config.Load handles this internally):
       No — `synth` is NOT needed in main.go. `config.Load` returns the full map. Only add `config` import.

    3. Add flag registration in main() after the `readPath` flag line (line 44):
       ```go
       rootCmd.Flags().StringVar(&configPath, "config", "", "Path to TOML config file (default: auto-discover)")
       ```

    4. In the `run` function, add config loading AFTER the BPF filter validation block (after line 80) and BEFORE output path resolution (before line 83). This is per D-11 (fail fast on config errors before capture):
       ```go
       // Load config (CFG-01 through CFG-05, D-11: fail fast)
       freqCfgs, err := config.Load(configPath)
       if err != nil {
           return err
       }
       ```

    5. The `freqCfgs` variable must be accessible in both `runLiveMode` and `runPcapMode`. Two approaches:
       - Option A: Pass freqCfgs to both functions (cleanest).
       - Option B: Store in a package-level var (simpler change).

       Use Option A. Change signatures:
       - `runLiveMode(cmd *cobra.Command) error` -> `runLiveMode(cmd *cobra.Command, freqCfgs map[classify.TrafficClass]synth.FreqConfig) error`
       - `runPcapMode(cmd *cobra.Command) error` -> `runPcapMode(cmd *cobra.Command, freqCfgs map[classify.TrafficClass]synth.FreqConfig) error`

       This requires adding `synth` import after all:
       ```go
       "github.com/netsynth/netsynth/synth"
       ```

       Update call sites in `run()`:
       - Line 92: `return runPcapMode(cmd)` -> `return runPcapMode(cmd, freqCfgs)`
       - Line 94: `return runLiveMode(cmd)` -> `return runLiveMode(cmd, freqCfgs)`

    6. In `runLiveMode`, change the RunSynthesis call (line 147):
       From: `encode.RunSynthesis(collectedSnapshots, outputPath)`
       To: `encode.RunSynthesis(collectedSnapshots, outputPath, freqCfgs)`

    7. In `runPcapMode`, change the RunSynthesis call (line 215):
       From: `encode.RunSynthesis(collectedSnapshots, outputPath)`
       To: `encode.RunSynthesis(collectedSnapshots, outputPath, freqCfgs)`

    After all changes, run `go build ./cmd/netsynth/...` to verify compilation.
  </action>
  <verify>
    <automated>cd /home/dev/workspace/yoloyolo && go build ./cmd/netsynth/... && go vet ./cmd/netsynth/... && go test ./... -count=1 2>&1 | tail -20</automated>
  </verify>
  <acceptance_criteria>
    - cmd/netsynth/main.go contains `configPath string`
    - cmd/netsynth/main.go contains `rootCmd.Flags().StringVar(&configPath, "config", ""`
    - cmd/netsynth/main.go contains `config.Load(configPath)`
    - cmd/netsynth/main.go contains `"github.com/netsynth/netsynth/config"` in imports
    - cmd/netsynth/main.go contains `encode.RunSynthesis(collectedSnapshots, outputPath, freqCfgs)` (two occurrences — one in runLiveMode, one in runPcapMode)
    - cmd/netsynth/main.go contains `runLiveMode(cmd, freqCfgs)` and `runPcapMode(cmd, freqCfgs)`
    - `go build ./cmd/netsynth/...` exits 0
    - `go vet ./cmd/netsynth/...` exits 0
    - `go test ./... -count=1` exits 0 (full suite green)
  </acceptance_criteria>
  <done>
    --config flag registered in Cobra. config.Load called at startup before capture. Merged config map flows through to RunSynthesis in both live and pcap modes. Full test suite passes.
  </done>
</task>

</tasks>

<verification>
- `go build ./...` compiles entire project
- `go test ./... -count=1` all tests pass
- `go vet ./...` no issues
- `./netsynth --help` shows `--config` flag in output
</verification>

<success_criteria>
- --config flag appears in CLI help output (CFG-03)
- Explicit --config with missing file produces error before capture (CFG-03)
- RunSynthesis uses injected config map, not hardcoded ClassFreqConfigs (D-10)
- Full test suite passes including encode and config package tests
</success_criteria>

<output>
After completion, create `.planning/phases/06-config-package-and-sound-overrides/06-02-SUMMARY.md`
</output>