package config

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

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
	"go.uber.org/fx"
	"go.uber.org/fx/fxtest"
	"sneak.berlin/go/webhooker/internal/globals"
	"sneak.berlin/go/webhooker/internal/logger"
)

func TestEnvironmentConfig(t *testing.T) {
	tests := []struct {
		name        string
		envValue    string
		envVars     map[string]string
		expectError bool
		isDev       bool
		isProd      bool
	}{
		{
			name:        "default is dev",
			envValue:    "",
			envVars:     map[string]string{},
			expectError: false,
			isDev:       true,
			isProd:      false,
		},
		{
			name:        "explicit dev",
			envValue:    "dev",
			envVars:     map[string]string{},
			expectError: false,
			isDev:       true,
			isProd:      false,
		},
		{
			name:        "explicit prod",
			envValue:    "prod",
			envVars:     map[string]string{},
			expectError: false,
			isDev:       false,
			isProd:      true,
		},
		{
			name:        "invalid environment",
			envValue:    "staging",
			envVars:     map[string]string{},
			expectError: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			// Set environment variable if specified
			if tt.envValue != "" {
				os.Setenv("WEBHOOKER_ENVIRONMENT", tt.envValue)
				defer os.Unsetenv("WEBHOOKER_ENVIRONMENT")
			} else {
				os.Unsetenv("WEBHOOKER_ENVIRONMENT")
			}

			// Set additional environment variables
			for k, v := range tt.envVars {
				os.Setenv(k, v)
				defer os.Unsetenv(k)
			}

			if tt.expectError {
				// Use regular fx.New for error cases since fxtest doesn't expose errors the same way
				var cfg *Config
				app := fx.New(
					fx.NopLogger, // Suppress fx logs in tests
					fx.Provide(
						globals.New,
						logger.New,
						New,
					),
					fx.Populate(&cfg),
				)
				assert.Error(t, app.Err())
			} else {
				// Use fxtest for success cases
				var cfg *Config
				app := fxtest.New(
					t,
					fx.Provide(
						globals.New,
						logger.New,
						New,
					),
					fx.Populate(&cfg),
				)
				require.NoError(t, app.Err())
				app.RequireStart()
				defer app.RequireStop()

				assert.Equal(t, tt.isDev, cfg.IsDev())
				assert.Equal(t, tt.isProd, cfg.IsProd())
			}
		})
	}
}

func TestDevDataDir(t *testing.T) {
	t.Run("uses XDG_DATA_HOME when set", func(t *testing.T) {
		os.Setenv("XDG_DATA_HOME", "/custom/data")
		defer os.Unsetenv("XDG_DATA_HOME")

		got := devDataDir()
		assert.Equal(t, "/custom/data/webhooker", got)
	})

	t.Run("falls back to HOME/.local/share/webhooker", func(t *testing.T) {
		os.Unsetenv("XDG_DATA_HOME")

		home, err := os.UserHomeDir()
		require.NoError(t, err)

		got := devDataDir()
		assert.Equal(t, filepath.Join(home, ".local", "share", "webhooker"), got)
	})

	t.Run("result is always absolute", func(t *testing.T) {
		os.Unsetenv("XDG_DATA_HOME")

		got := devDataDir()
		assert.True(t, filepath.IsAbs(got), "devDataDir() returned relative path: %s", got)
	})
}

func TestDevDefaultDataDirIsAbsolute(t *testing.T) {
	// Verify that when WEBHOOKER_ENVIRONMENT=dev and DATA_DIR is unset,
	// the resulting DataDir is an absolute path.
	os.Unsetenv("WEBHOOKER_ENVIRONMENT")
	os.Unsetenv("DATA_DIR")

	var cfg *Config
	app := fxtest.New(
		t,
		fx.Provide(
			globals.New,
			logger.New,
			New,
		),
		fx.Populate(&cfg),
	)
	require.NoError(t, app.Err())
	app.RequireStart()
	defer app.RequireStop()

	assert.True(t, filepath.IsAbs(cfg.DataDir),
		"dev default DataDir should be absolute, got: %s", cfg.DataDir)
}