package yamlutil

import (
	"testing"

	"gopkg.in/yaml.v3"
)

func TestUnmarshal_NoDuplicates(t *testing.T) {
	data := []byte("a: 1\nb: 2\n")
	var out map[string]interface{}
	if err := Unmarshal(data, &out); err != nil {
		t.Fatalf("Unmarshal() error = %v", err)
	}
	if out["a"] != 1 || out["b"] != 2 {
		t.Fatalf("unexpected result: %#v", out)
	}
}

func TestUnmarshal_DuplicateKeyLastWins(t *testing.T) {
	// Mirrors the real bug: a duplicate top-level key that gopkg.in/yaml.v3
	// rejects outright, but PyYAML (and this package) tolerate by letting
	// the later occurrence win.
	data := []byte(`external-controller-cors:
  allow-origins:
    - "*"
  allow-private-network: true
  allow-origins:
    - tauri://localhost
    - https://yacd.metacubex.one
`)

	// Confirm plain yaml.Unmarshal actually fails on this input, i.e. that
	// the test is exercising the real bug.
	var control map[string]interface{}
	if err := yaml.Unmarshal(data, &control); err == nil {
		t.Fatalf("expected plain yaml.Unmarshal to fail on duplicate keys, it didn't")
	}

	var out map[string]interface{}
	if err := Unmarshal(data, &out); err != nil {
		t.Fatalf("Unmarshal() error = %v", err)
	}

	cors, ok := out["external-controller-cors"].(map[string]interface{})
	if !ok {
		t.Fatalf("expected external-controller-cors map, got %#v", out["external-controller-cors"])
	}

	origins, ok := cors["allow-origins"].([]interface{})
	if !ok || len(origins) != 2 {
		t.Fatalf("expected last allow-origins (2 entries) to win, got %#v", cors["allow-origins"])
	}
	if origins[0] != "tauri://localhost" {
		t.Fatalf("expected last-occurrence value to win, got %#v", origins)
	}
	if cors["allow-private-network"] != true {
		t.Fatalf("expected sibling key to survive dedupe, got %#v", cors)
	}
}

func TestUnmarshal_NestedDuplicates(t *testing.T) {
	data := []byte(`outer:
  inner:
    x: 1
    x: 2
  inner:
    y: 3
`)
	var out map[string]interface{}
	if err := Unmarshal(data, &out); err != nil {
		t.Fatalf("Unmarshal() error = %v", err)
	}
	outer := out["outer"].(map[string]interface{})
	inner := outer["inner"].(map[string]interface{})
	if _, hasX := inner["x"]; hasX {
		t.Fatalf("expected last 'inner' occurrence to fully replace the first, got %#v", inner)
	}
	if inner["y"] != 3 {
		t.Fatalf("expected inner.y == 3, got %#v", inner)
	}
}

func TestUnmarshal_Empty(t *testing.T) {
	var out map[string]interface{}
	if err := Unmarshal([]byte(""), &out); err != nil {
		t.Fatalf("Unmarshal() error = %v", err)
	}
	if out != nil {
		t.Fatalf("expected nil map for empty input, got %#v", out)
	}
}

func TestUnmarshal_Sequence(t *testing.T) {
	data := []byte("- a: 1\n  a: 2\n- b: 3\n")
	var out []map[string]interface{}
	if err := Unmarshal(data, &out); err != nil {
		t.Fatalf("Unmarshal() error = %v", err)
	}
	if len(out) != 2 || out[0]["a"] != 2 || out[1]["b"] != 3 {
		t.Fatalf("unexpected result: %#v", out)
	}
}