package config

import (
	"os"
	"path/filepath"
	"testing"
)

func TestDefaults(t *testing.T) {
	cfg, err := Load(nil)
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if cfg.Port != "8080" {
		t.Fatalf("Port = %q, want 8080", cfg.Port)
	}
	if cfg.DBDriver != "sqlite" {
		t.Fatalf("DBDriver = %q, want sqlite", cfg.DBDriver)
	}
	if got := cfg.Addresses(); len(got) != 1 || got[0] != "0.0.0.0:8080" {
		t.Fatalf("Addresses = %v, want [0.0.0.0:8080]", got)
	}
}

func TestPrecedence(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.yaml")
	content := `
logLevel: debug
port: "9090"
listenAddr: "127.0.0.1"
dbDsn: "file:from-file.db"
corsOrigins:
  - "https://forms.example.com"
`
	if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
		t.Fatal(err)
	}

	t.Setenv("KERERU_LOG_LEVEL", "warn")
	t.Setenv("KERERU_PORT", "9091")

	cfg, err := Load([]string{"--conf", path, "--port", "9092"})
	if err != nil {
		t.Fatalf("Load: %v", err)
	}

	if cfg.LogLevel != "warn" {
		t.Fatalf("LogLevel = %q, want env override warn", cfg.LogLevel)
	}
	if cfg.Port != "9092" {
		t.Fatalf("Port = %q, want flag override 9092", cfg.Port)
	}
	if cfg.HTTPAddr != "127.0.0.1" {
		t.Fatalf("HTTPAddr = %q, want file value", cfg.HTTPAddr)
	}
	if cfg.DBDSN != "file:from-file.db" {
		t.Fatalf("DBDSN = %q, want file value", cfg.DBDSN)
	}
	if len(cfg.CORSOrigins) != 1 || cfg.CORSOrigins[0] != "https://forms.example.com" {
		t.Fatalf("CORSOrigins = %v", cfg.CORSOrigins)
	}
}

func TestJSONConfigAndIPv6(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, "config.json")
	content := `{"listenAddr":"","listenAddr6":"::1","port":"8081"}`
	if err := os.WriteFile(path, []byte(content), 0o600); err != nil {
		t.Fatal(err)
	}

	cfg, err := Load([]string{"--conf=" + path})
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	addrs := cfg.Addresses()
	if len(addrs) != 1 || addrs[0] != "[::1]:8081" {
		t.Fatalf("Addresses = %v, want [[::1]:8081]", addrs)
	}
}

func TestValidateRequiresListener(t *testing.T) {
	cfg := Default()
	cfg.HTTPAddr = ""
	cfg.HTTPAddr6 = ""
	if err := cfg.Validate(); err == nil {
		t.Fatal("expected validation error when no listener is configured")
	}
}

func TestInvalidPort(t *testing.T) {
	if _, err := Load([]string{"--port", "not-a-port"}); err == nil {
		t.Fatal("expected validation error for invalid port")
	}
}