package app

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

	"gitea.maximumdirect.net/eric/weatherreporter/internal/testutil"
)

func TestResolveComparisonOutputDirectory(t *testing.T) {
	workingDir := t.TempDir()
	configured := filepath.Join(workingDir, "configured")
	blocked := filepath.Join(workingDir, "not-a-directory")
	if err := os.WriteFile(blocked, []byte("blocked"), 0o600); err != nil {
		t.Fatal(err)
	}

	tests := []struct {
		name             string
		override         string
		configuredDir    string
		reportOutputName string
		want             string
		wantErr          bool
	}{
		{name: "working directory default", reportOutputName: "today.md", want: filepath.Join(workingDir, "comparison-today")},
		{name: "configured relative directory", configuredDir: "configured", reportOutputName: "tomorrow.md", want: filepath.Join(configured, "comparison-tomorrow")},
		{name: "configured absolute directory", configuredDir: configured, reportOutputName: "hourly.md", want: filepath.Join(configured, "comparison-hourly")},
		{name: "relative explicit directory", override: "exact", configuredDir: blocked, reportOutputName: "daily-2026-08-24.md", want: filepath.Join(workingDir, "exact")},
		{name: "absolute explicit directory", override: filepath.Join(workingDir, "absolute"), reportOutputName: "today.md", want: filepath.Join(workingDir, "absolute")},
		{name: "invalid report suffix", reportOutputName: "today.txt", wantErr: true},
	}

	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			got, err := resolveComparisonOutputDirectory(workingDir, test.override, test.configuredDir, test.reportOutputName)
			if (err != nil) != test.wantErr {
				t.Fatalf("resolveComparisonOutputDirectory() error = %v, want error %t", err, test.wantErr)
			}
			if !test.wantErr && got != test.want {
				t.Fatalf("resolveComparisonOutputDirectory() = %q, want %q", got, test.want)
			}
		})
	}
}

func TestResolveOutputDirRejectsDanglingSymlinkComponents(t *testing.T) {
	workingDir := t.TempDir()
	dangling := filepath.Join(workingDir, "dangling")
	testutil.RequireSymlink(t, filepath.Join(workingDir, "missing"), dangling)

	for _, directory := range []string{dangling, filepath.Join(dangling, "reports")} {
		t.Run(filepath.Base(directory), func(t *testing.T) {
			if _, err := resolveOutputDir(workingDir, directory); err == nil {
				t.Fatalf("resolveOutputDir(%q) error = nil, want dangling symlink error", directory)
			}
		})
	}
}

func TestResolveOutputDirAllowsMissingDirectoryBelowValidSymlink(t *testing.T) {
	workingDir := t.TempDir()
	target := t.TempDir()
	link := filepath.Join(workingDir, "linked")
	testutil.RequireSymlink(t, target, link)

	directory := filepath.Join(link, "reports")
	got, err := resolveOutputDir(workingDir, directory)
	if err != nil || got != directory {
		t.Fatalf("resolveOutputDir() = %q, %v, want %q, nil", got, err, directory)
	}
}