package adminapi

import (
	"context"
	"encoding/json"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"slices"
	"strings"
	"testing"
	"time"

	"gitea.mynodes.xyz/ilker/llmgw/internal/agent/discovery"
	"gitea.mynodes.xyz/ilker/llmgw/internal/agent/weights"
	"gitea.mynodes.xyz/ilker/llmgw/internal/control"
	"gitea.mynodes.xyz/ilker/llmgw/internal/control/catalog"
	"gitea.mynodes.xyz/ilker/llmgw/internal/control/inventory"
)

// deletingDispatcher deletes what it is asked to as a node would, by its
// files dropping out of what the node lists — but for refused, which it
// keeps, as an agent keeps a file it cannot prove it fetched.
type deletingDispatcher struct {
	nullDispatcher
	inv     *inventory.Store
	refused string
}

func (d *deletingDispatcher) RemoveWeights(_ context.Context, node string, paths []string) error {
	n, _ := d.inv.Get(node)
	n.Weights = slices.DeleteFunc(n.Weights, func(w discovery.LocalWeights) bool {
		return w.Path != d.refused && slices.Contains(paths, w.Path)
	})
	d.inv.Upsert(n)
	return nil
}

// What a sweep says it freed is what the node no longer lists: a file it
// kept is said to be left, not counted as freed.
func TestASweepSaysWhatWasDeletedNotWhatWasAsked(t *testing.T) {
	confirmWait = 1500 * time.Millisecond
	t.Cleanup(func() { confirmWait = 30 * time.Second })

	gone := weights.CachePathFor("/var/lib/llmgw-weights", "http://mirror/old/v1/old.gguf")
	set := weights.CachePathFor("/var/lib/llmgw-weights", "http://mirror/big/v1")
	kept := weights.CachePathFor("/var/lib/llmgw-weights", "http://mirror/stuck/v1/stuck.gguf")
	cat, _ := catalog.New(nil)
	d := &deletingDispatcher{refused: kept}
	ctl := control.New(control.DefaultConfig(), catalog.NewLive(cat), d, nullSink{}, slog.New(slog.DiscardHandler))
	d.inv = ctl.Inventory()
	node := gpuNode("n1", 1)
	node.Weights = []discovery.LocalWeights{{Path: gone, SizeBytes: 1 << 30}, {Path: set, SizeBytes: 20 << 30},
		{Path: kept, SizeBytes: 4 << 30}}
	ctl.Inventory().Upsert(node)
	a := New(ctl)

	rec := httptest.NewRecorder()
	a.collectWeights(rec, httptest.NewRequest(http.MethodPost, "/api/v1/weights/collect", strings.NewReader(`{"node":"n1"}`)))
	var got []CollectResult
	if err := json.Unmarshal(rec.Body.Bytes(), &got); err != nil {
		t.Fatalf("%v: %s", err, rec.Body.String())
	}
	if len(got) != 1 {
		t.Fatalf("results %+v", got)
	}
	r := got[0]
	if r.Files != 2 || r.Bytes != 21<<30 || r.Left != 1 || r.LeftBytes != 4<<30 {
		t.Errorf("result %+v: want 2 files and 21 GB freed, 1 file of 4 GB left", r)
	}
}