package main

import (
	"fmt"
	"os"

	"github.com/kami/maven/internal/router"
	"github.com/kami/maven/internal/router/semantic"
)

// headsMain runs the deployed cascade minus the resident LLM: stage-0
// grammars → routing heads (fine-tuned e5 copy + softmax, router_heads.onnx,
// 0.6 decline threshold) → ONNX-embedder nearest-centroid classifier →
// 0.55 confidence gate. This is what a production turn takes when the model
// server is out (docs/routing.md: pickLLMRouter degrades to the classifier).
//
// The classifier is seeded from models/seeds like the daemon's seedClassifier,
// embedded with the real multilingual-e5-small model rather than the block
// hash, so this is the closest headless reproduction of the authoritative
// router output the slice-22 report can run.
//
// Requires the ONNX model files and a libonnxruntime.so. Pass the library via
// the MAVEN_ONNX_LIB environment variable, exactly as the daemon does.
func headsMain(poolPath, outPath string) {
	lib := os.Getenv("MAVEN_ONNX_LIB")
	if lib == "" {
		fmt.Fprintln(os.Stderr, "heads mode needs MAVEN_ONNX_LIB pointing at libonnxruntime.so")
		os.Exit(2)
	}
	const (
		embedModel   = "models/embedder/multilingual-e5-small/model_quantized.onnx"
		tokPath      = "models/embedder/multilingual-e5-small/tokenizer.json"
		headsModel   = "models/embedder/router-heads/router_heads.onnx"
	)
	emb, err := router.NewONNXEmbedder(embedModel, tokPath, lib)
	if err != nil {
		fmt.Fprintf(os.Stderr, "heads: embedder: %v\n", err)
		os.Exit(1)
	}
	defer emb.Close()

	cls := router.NewClassifier(emb)
	seedClassifier(cls)

	heads, err := router.NewRouterHeads(headsModel, tokPath)
	if err != nil {
		fmt.Fprintf(os.Stderr, "heads: %v\n", err)
		os.Exit(1)
	}
	defer heads.Close()

	acts := router.DefaultActMatcher{Fns: semantic.ExperimentActVerbs()}
	r := router.New(router.Config{
		Grammars:   router.StageZeroGrammars(acts),
		Classifier: cls,
		Extractor: router.Extractor{
			Time:  router.StubDateTimeParser{},
			Acts:  acts,
			Facts: router.DefaultFactParser{},
		},
		Threshold: 0.55,
		Heads:     heads,
	})
	runOverPool(r, poolPath, outPath)
}