package config

import (
	"os"
	"testing"
	"time"
)

// clearUploadEnv unsets every upload knob so a test observes the default, not the
// host environment.
func clearUploadEnv(t *testing.T) {
	t.Helper()
	for _, k := range []string{
		"TAPIR_UPLOADS_ENABLED", "TAPIR_UPLOAD_MAX_MB", "TAPIR_UPLOAD_MAX_MINUTES",
		"TAPIR_TRANSCRIBE_MODEL", "TAPIR_TRANSCRIBE_FALLBACK_MODEL", "TAPIR_TRANSCRIBE_TIMEOUT",
		"TAPIR_UPLOAD_TMP_DIR", "TAPIR_FFMPEG_BIN", "TAPIR_FFPROBE_BIN",
		"TAPIR_MAX_UPLOADED_TRANSCRIPT_CHARS",
	} {
		unset(t, k)
	}
}

func TestLoad_UploadDefaults(t *testing.T) {
	clearUploadEnv(t)

	c, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}

	if c.UploadsEnabled {
		t.Error("uploads must be OFF by default: the runtime image needs ffmpeg first (ADR-033)")
	}
	if c.UploadMaxBytes != 200<<20 {
		t.Errorf("UploadMaxBytes = %d, want 200 MB", c.UploadMaxBytes)
	}
	if c.UploadMaxDuration != 90*time.Minute {
		t.Errorf("UploadMaxDuration = %v, want 90m (the longest length measured, not a found ceiling)", c.UploadMaxDuration)
	}
	if c.TranscribeModel != "iguana/kb-whisper" {
		t.Errorf("TranscribeModel = %q", c.TranscribeModel)
	}
	if c.TranscribeFallbackModel != "berget/kb-whisper" {
		t.Errorf("TranscribeFallbackModel = %q", c.TranscribeFallbackModel)
	}
	if c.TranscribeTimeout != 30*time.Minute {
		t.Errorf("TranscribeTimeout = %v, want 30m (a 90 min recording took ~7.5 min)", c.TranscribeTimeout)
	}
	if c.UploadTmpDir != os.TempDir() {
		t.Errorf("UploadTmpDir = %q, want os.TempDir()", c.UploadTmpDir)
	}
	if c.FFmpegBin != "ffmpeg" || c.FFprobeBin != "ffprobe" {
		t.Errorf("bins = %q, %q", c.FFmpegBin, c.FFprobeBin)
	}
	if c.MaxUploadedTranscriptChars != 120000 {
		t.Errorf("MaxUploadedTranscriptChars = %d, want 120000", c.MaxUploadedTranscriptChars)
	}
}

func TestLoad_UploadValuesAreParsed(t *testing.T) {
	clearUploadEnv(t)
	setEnv(t, map[string]string{
		"TAPIR_UPLOADS_ENABLED":               "true",
		"TAPIR_UPLOAD_MAX_MB":                 "50",
		"TAPIR_UPLOAD_MAX_MINUTES":            "30",
		"TAPIR_TRANSCRIBE_MODEL":              "koala/whisper",
		"TAPIR_TRANSCRIBE_TIMEOUT":            "10m",
		"TAPIR_UPLOAD_TMP_DIR":                "/var/spool/tapir",
		"TAPIR_FFMPEG_BIN":                    "/opt/ffmpeg",
		"TAPIR_FFPROBE_BIN":                   "/opt/ffprobe",
		"TAPIR_MAX_UPLOADED_TRANSCRIPT_CHARS": "60000",
	})

	c, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}

	if !c.UploadsEnabled || c.UploadMaxBytes != 50<<20 || c.UploadMaxDuration != 30*time.Minute ||
		c.TranscribeModel != "koala/whisper" || c.TranscribeTimeout != 10*time.Minute ||
		c.UploadTmpDir != "/var/spool/tapir" || c.FFmpegBin != "/opt/ffmpeg" ||
		c.FFprobeBin != "/opt/ffprobe" || c.MaxUploadedTranscriptChars != 60000 {
		t.Errorf("values not applied: %+v", c)
	}
}

func TestLoad_EmptyTranscribeFallbackDisablesIt(t *testing.T) {
	clearUploadEnv(t)
	t.Setenv("TAPIR_TRANSCRIBE_FALLBACK_MODEL", "")

	c, err := Load()
	if err != nil {
		t.Fatalf("Load: %v", err)
	}

	if c.TranscribeFallbackModel != "" {
		t.Errorf("TranscribeFallbackModel = %q: an explicit empty value must disable the cloud fallback, "+
			"so private audio can be kept on the homelab", c.TranscribeFallbackModel)
	}
}

func TestLoad_UploadRejectsInvalidValues(t *testing.T) {
	tests := []struct{ key, val string }{
		{"TAPIR_UPLOADS_ENABLED", "maybe"},
		{"TAPIR_UPLOAD_MAX_MB", "lots"},
		{"TAPIR_UPLOAD_MAX_MB", "0"},
		{"TAPIR_UPLOAD_MAX_MB", "-5"},
		{"TAPIR_UPLOAD_MAX_MINUTES", "0"},
		{"TAPIR_UPLOAD_MAX_MINUTES", "forever"},
		{"TAPIR_TRANSCRIBE_TIMEOUT", "soon"},
		{"TAPIR_TRANSCRIBE_TIMEOUT", "0s"},
	}
	for _, tt := range tests {
		t.Run(tt.key+"="+tt.val, func(t *testing.T) {
			clearUploadEnv(t)
			t.Setenv(tt.key, tt.val)

			if _, err := Load(); err == nil {
				t.Errorf("Load accepted %s=%q; a zero or negative limit would reject every upload", tt.key, tt.val)
			}
		})
	}
}