package main

import (
	"testing"

	"mgit.msbls.de/m/ImaGen/internal/config"
	"mgit.msbls.de/m/ImaGen/internal/preview"
)

func TestResolvePreviewMode(t *testing.T) {
	type tc struct {
		name      string
		cfg       *config.Config
		flagOn    bool
		flagOff   bool
		env       string
		want      preview.Mode
		wantError bool
	}
	cases := []tc{
		{name: "all-empty-defaults-to-auto", want: preview.ModeAuto},
		{name: "config-on", cfg: &config.Config{Output: config.OutputConfig{Preview: "on"}}, want: preview.ModeOn},
		{name: "config-off", cfg: &config.Config{Output: config.OutputConfig{Preview: "off"}}, want: preview.ModeOff},
		{name: "config-auto-explicit", cfg: &config.Config{Output: config.OutputConfig{Preview: "auto"}}, want: preview.ModeAuto},
		{name: "env-overrides-config", cfg: &config.Config{Output: config.OutputConfig{Preview: "on"}}, env: "off", want: preview.ModeOff},
		{name: "flag-on-overrides-env-off", env: "off", flagOn: true, want: preview.ModeOn},
		{name: "flag-off-overrides-env-on", env: "on", flagOff: true, want: preview.ModeOff},
		{name: "flag-off-overrides-config-on", cfg: &config.Config{Output: config.OutputConfig{Preview: "on"}}, flagOff: true, want: preview.ModeOff},
		{name: "both-flags-error", flagOn: true, flagOff: true, wantError: true},
		{name: "bad-env-errors", env: "yes", wantError: true},
		{name: "bad-config-errors", cfg: &config.Config{Output: config.OutputConfig{Preview: "yes"}}, wantError: true},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			got, err := resolvePreviewMode(c.cfg, c.flagOn, c.flagOff, c.env)
			if c.wantError {
				if err == nil {
					t.Fatalf("expected error, got mode %q", got)
				}
				return
			}
			if err != nil {
				t.Fatalf("unexpected error: %v", err)
			}
			if got != c.want {
				t.Errorf("mode = %q, want %q", got, c.want)
			}
		})
	}
}