feat: done vibing

internal/analyze/split.go

@@ -0,0 +1,65 @@
+package analyze
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+
+	"github.com/ytshih/stonks/internal/report"
+)
+
+// recommendationsMarker must match the marker text SystemPrompt instructs
+// Claude to emit before the trailing recommendations JSON block.
+const recommendationsMarker = "===RECOMMENDATIONS_JSON==="
+
+type recommendationsPayload struct {
+	Recommendations []report.Recommendation `json:"recommendations"`
+}
+
+// SplitReport separates Claude's raw response into the long-form narrative
+// text and the short buy/sell recommendations list appended after
+// recommendationsMarker (see SystemPrompt).
+//
+// If the marker is missing or the trailing JSON fails to parse, the full raw
+// text is returned as-is with a nil recommendations slice, plus a non-nil
+// error — callers should log it as a warning and still send the text-only
+// report rather than treat this as fatal.
+func SplitReport(raw string) (report.Report, error) {
+	idx := strings.Index(raw, recommendationsMarker)
+	if idx == -1 {
+		return report.Report{Text: strings.TrimSpace(raw)},
+			fmt.Errorf("recommendations marker not found in response")
+	}
+
+	text := strings.TrimSpace(raw[:idx])
+	jsonPart := extractJSONObject(raw[idx+len(recommendationsMarker):])
+
+	var payload recommendationsPayload
+	if err := json.Unmarshal([]byte(jsonPart), &payload); err != nil {
+		return report.Report{Text: text}, fmt.Errorf("parse recommendations json: %w", err)
+	}
+
+	for _, r := range payload.Recommendations {
+		if r.Action != "buy" && r.Action != "sell" {
+			return report.Report{Text: text}, fmt.Errorf("recommendation for %q has invalid action %q", r.Symbol, r.Action)
+		}
+	}
+
+	return report.Report{Text: text, Recommendations: payload.Recommendations}, nil
+}
+
+// extractJSONObject pulls out the substring from the first "{" to the last
+// "}" in s. This tolerates any decoration Claude adds around the JSON
+// despite being asked not to — a ```json fence, a stray leading backtick, a
+// trailing sentence — since none of that can contain a brace that comes
+// before the real opening one or after the real closing one. Returns s
+// trimmed, unchanged, if no braces are found (json.Unmarshal will then fail
+// with a clear error).
+func extractJSONObject(s string) string {
+	start := strings.IndexByte(s, '{')
+	end := strings.LastIndexByte(s, '}')
+	if start == -1 || end == -1 || end < start {
+		return strings.TrimSpace(s)
+	}
+	return s[start : end+1]
+}