package jsonfile

import (
	"encoding/json"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestWriteFormatsWithTwoSpaceIndentAndTrailingNewline(t *testing.T) {
	type payload struct {
		Name  string `json:"name"`
		Items []int  `json:"items"`
	}

	path := filepath.Join(t.TempDir(), "out.json")
	value := payload{
		Name:  "alpha",
		Items: []int{1, 2},
	}

	if err := Write(path, value); err != nil {
		t.Fatalf("write failed: %v", err)
	}

	data, err := os.ReadFile(path)
	if err != nil {
		t.Fatalf("read output: %v", err)
	}

	got := string(data)
	want := "{\n  \"name\": \"alpha\",\n  \"items\": [\n    1,\n    2\n  ]\n}\n"
	if got != want {
		t.Fatalf("formatted JSON mismatch\nwant:\n%s\ngot:\n%s", want, got)
	}
}

func TestWriteProducesValidJSON(t *testing.T) {
	path := filepath.Join(t.TempDir(), "out.json")

	value := map[string]any{
		"application": "seriatim",
		"segments": []map[string]any{
			{
				"id":      1,
				"speaker": "A",
				"text":    "hello",
			},
		},
	}

	if err := Write(path, value); err != nil {
		t.Fatalf("write failed: %v", err)
	}

	data, err := os.ReadFile(path)
	if err != nil {
		t.Fatalf("read output: %v", err)
	}
	if !strings.HasSuffix(string(data), "\n") {
		t.Fatalf("output missing trailing newline: %q", string(data))
	}

	var decoded map[string]any
	if err := json.Unmarshal(data, &decoded); err != nil {
		t.Fatalf("output is not valid JSON: %v", err)
	}
}