package agents

import (
	"context"
	"encoding/json"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"g.fc.run/misc/byre/internal/api"
	"g.fc.run/misc/byre/internal/store"
)

func TestSetMergeTitle(t *testing.T) {
	ctx := context.Background()
	st, err := store.Open(filepath.Join(t.TempDir(), "byre.db"), func(api.Event) {})
	if err != nil {
		t.Fatalf("open store: %v", err)
	}
	t.Cleanup(func() { st.Close() })

	now := time.Now().UTC()
	_, err = st.EnsureUser(ctx, "alice", "Alice")
	if err != nil {
		t.Fatalf("ensure user: %v", err)
	}
	err = st.CreateProject(ctx, api.Project{Id: "p1", Name: "demo", RepoPath: "/nonexistent", DefaultBranch: "main", Remote: "none", CreatedBy: "alice", CreatedAt: now})
	if err != nil {
		t.Fatalf("create project: %v", err)
	}
	err = st.CreateTask(ctx, api.Task{Id: "t1", ProjectId: "p1", Title: "Fix the thing", Branch: "b", WorktreePath: "/nonexistent", BaseRef: "x", Status: api.TaskStatusActive, CreatedBy: "alice", CreatedAt: now}, "alice")
	if err != nil {
		t.Fatalf("create task: %v", err)
	}

	task, err := st.GetTask(ctx, "t1")
	if err != nil || task.MergeTitle != "Fix the thing" {
		t.Fatalf("default merge title %q, want the task title: %v", task.MergeTitle, err)
	}

	m := New(st, DefaultLimits, t.TempDir(), t.TempDir())
	l := &live{id: "s1", vendor: api.Claude, taskID: "t1", projectID: "p1"}
	call := func(title string) error {
		raw, err := json.Marshal(setMergeTitleArgs{Title: title})
		if err != nil {
			t.Fatalf("marshal: %v", err)
		}
		_, err = m.setMergeTitle(ctx, l, raw)
		return err
	}

	for _, bad := range []string{"", "  ", "two\nlines", strings.Repeat("x", maxMergeTitle+1)} {
		if call(bad) == nil {
			t.Fatalf("set_merge_title accepted %q", bad)
		}
	}

	err = call("  Add retry with backoff to webhook delivery ")
	if err != nil {
		t.Fatalf("set_merge_title: %v", err)
	}
	task, err = st.GetTask(ctx, "t1")
	if err != nil || task.MergeTitle != "Add retry with backoff to webhook delivery" || task.Title != "Fix the thing" {
		t.Fatalf("after set_merge_title: %+v %v", task, err)
	}

	if !strings.Contains(mergeInPrompt("main", task.MergeTitle), `currently "Add retry with backoff to webhook delivery"`) {
		t.Fatalf("merge-in prompt doesn't show the current title: %s", mergeInPrompt("main", task.MergeTitle))
	}

	_, err = st.DiscardTask(ctx, "t1", "alice")
	if err != nil {
		t.Fatalf("discard: %v", err)
	}
	if call("Too late") == nil {
		t.Fatalf("set_merge_title accepted a title for a closed task")
	}
}