package config

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

func writeFile(t *testing.T, name string, mode os.FileMode, content string) string {
	t.Helper()
	path := filepath.Join(t.TempDir(), name)
	if err := os.WriteFile(path, []byte(content), mode); err != nil {
		t.Fatal(err)
	}
	return path
}

func TestLoadEnvOnly(t *testing.T) {
	t.Setenv("MRED_URL", "https://redmine.example/")
	t.Setenv("MRED_KEY", "k1")
	cfg, src, err := Load("")
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if cfg.BaseURL != "https://redmine.example" {
		t.Errorf("BaseURL = %q, want trailing slash trimmed", cfg.BaseURL)
	}
	if cfg.APIKey != "k1" {
		t.Errorf("APIKey = %q", cfg.APIKey)
	}
	if src.Env == "" {
		t.Errorf("source env = %q, want a key name", src.Env)
	}
}

func TestLoadFileOnly(t *testing.T) {
	path := writeFile(t, "env", 0o600, "MRED_URL=https://r.example\nMRED_KEY=k2\n")
	cfg, _, err := Load(path)
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if cfg.BaseURL != "https://r.example" || cfg.APIKey != "k2" {
		t.Errorf("cfg = %+v", cfg)
	}
}

func TestLoadEnvWinsOverFile(t *testing.T) {
	t.Setenv("MRED_KEY", "envkey")
	path := writeFile(t, "env", 0o600, "MRED_URL=https://r.example\nMRED_KEY=filekey\n")
	cfg, src, err := Load(path)
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if cfg.APIKey != "envkey" {
		t.Errorf("APIKey = %q, want env value to win", cfg.APIKey)
	}
	if src.File != "" && src.Env != "MRED_KEY" {
		t.Errorf("source = %+v", src)
	}
}

func TestLoadRejectsLooseFile(t *testing.T) {
	path := writeFile(t, "env", 0o644, "MRED_URL=https://r.example\nMRED_KEY=k\n")
	_, _, err := Load(path)
	if err == nil || !strings.Contains(err.Error(), "insecure mode") {
		t.Fatalf("err = %v, want insecure-mode rejection", err)
	}
}

func TestLoadMissingEverything(t *testing.T) {
	_, _, err := Load(filepath.Join(t.TempDir(), "absent"))
	if err == nil || !strings.Contains(err.Error(), "MRED_URL") {
		t.Fatalf("err = %v, want guidance naming MRED_URL/MRED_KEY", err)
	}
}

func TestLoadKeyAbsent(t *testing.T) {
	t.Setenv("MRED_URL", "https://r.example")
	path := writeFile(t, "env", 0o600, "# nothing useful\n")
	_, _, err := Load(path)
	if err == nil || !strings.Contains(err.Error(), "MRED_KEY") {
		t.Fatalf("err = %v, want MRED_KEY named", err)
	}
}

func TestLoadMalformedLineReportsNumberOnly(t *testing.T) {
	path := writeFile(t, "env", 0o600, "MRED_URL=https://r.example\nMRED_KEY=sekrit-value\nBROKEN LINE HERE\n")
	_, _, err := Load(path)
	if err == nil || !strings.Contains(err.Error(), "line 3") {
		t.Fatalf("err = %v, want line-number-only diagnostic", err)
	}
	if err != nil && strings.Contains(err.Error(), "sekrit-value") {
		t.Fatalf("err = %v leaks file contents", err)
	}
}

func TestLoadQuotedAndExported(t *testing.T) {
	path := writeFile(t, "env", 0o600, "export MRED_URL=\"https://r.example\"\nexport MRED_KEY='k3'\n")
	cfg, _, err := Load(path)
	if err != nil {
		t.Fatalf("Load: %v", err)
	}
	if cfg.BaseURL != "https://r.example" || cfg.APIKey != "k3" {
		t.Errorf("cfg = %+v, want quotes stripped", cfg)
	}
}