scenario.go

 1// Package scenario loads the plain-text brief that opens the game-loop LLM
 2// context. A scenario file is one to three sentences describing place, time,
 3// and vibe; the model invents everything else on the fly. The file name (base
 4// without extension) is the scenario name.
 5package scenario
 6
 7import (
 8	"fmt"
 9	"os"
10	"path/filepath"
11	"strings"
12)
13
14// Scenario is one brief: a display name plus the text that opens the
15// game-loop system prompt.
16type Scenario struct {
17	Name  string
18	Brief string
19}
20
21// Load reads and validates a scenario from path. Name is the file's base name
22// without extension; Brief is the trimmed file content. Both must be non-empty.
23func Load(path string) (Scenario, error) {
24	data, err := os.ReadFile(path)
25	if err != nil {
26		return Scenario{}, fmt.Errorf("scenario: read %s: %w", path, err)
27	}
28	brief := strings.TrimSpace(string(data))
29	name := strings.TrimSuffix(filepath.Base(path), filepath.Ext(path))
30	if name == "" {
31		return Scenario{}, fmt.Errorf("scenario: name must not be empty")
32	}
33	if brief == "" {
34		return Scenario{}, fmt.Errorf("scenario: brief must not be empty")
35	}
36	return Scenario{Name: name, Brief: brief}, nil
37}