package cmd

import (
	"strings"
	"testing"
)

func TestBuildPRDescribeMessages(t *testing.T) {
	tests := []struct {
		name     string
		diff     string
		sysCheck string
		usrCheck []string
	}{
		{
			name:     "branch with changes",
			diff:     "diff --git a/cmd/new.go b/cmd/new.go\n+package cmd",
			sysCheck: "PR",
			usrCheck: []string{"Diff:", "diff --git a/cmd/new.go"},
		},
		{
			name:     "empty diff",
			diff:     "",
			sysCheck: "PR",
			usrCheck: []string{"Diff:"},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			msgs := buildPRDescribeMessages(tt.diff)

			if len(msgs) != 2 {
				t.Fatalf("expected 2 messages, got %d", len(msgs))
			}
			if msgs[0]["role"] != "system" {
				t.Errorf("first message role = %q, want %q", msgs[0]["role"], "system")
			}
			if msgs[1]["role"] != "user" {
				t.Errorf("second message role = %q, want %q", msgs[1]["role"], "user")
			}
			if !strings.Contains(msgs[0]["content"], tt.sysCheck) {
				t.Errorf("system prompt missing %q; got: %s", tt.sysCheck, msgs[0]["content"])
			}
			for _, check := range tt.usrCheck {
				if !strings.Contains(msgs[1]["content"], check) {
					t.Errorf("user prompt missing %q", check)
				}
			}
		})
	}
}