package nvidia_bug_report

import (
	"bufio"
	"regexp"
	"strconv"
	"strings"
	"time"

	"git.mchus.pro/mchus/logpile/internal/models"
)

// parseGPUInfo extracts GPU information from the bug report
func parseGPUInfo(content string, result *models.AnalysisResult) {
	scanner := bufio.NewScanner(strings.NewReader(content))

	var currentGPU *models.GPU
	inGPUInfo := false

	for scanner.Scan() {
		line := scanner.Text()

		// Look for GPU information section markers (but skip ls listings)
		if strings.Contains(line, "/proc/driver/nvidia") && strings.Contains(line, "/gpus/") &&
		   strings.Contains(line, "/information") && !strings.Contains(line, "ls:") {
			// Extract PCI address
			re := regexp.MustCompile(`/gpus/([\da-f]{4}:[\da-f]{2}:[\da-f]{2}\.[\da-f])`)
			matches := re.FindStringSubmatch(line)
			if len(matches) > 1 {
				pciAddr := matches[1]

				// Save previous GPU if exists
				if currentGPU != nil {
					result.Hardware.GPUs = append(result.Hardware.GPUs, *currentGPU)
				}

				// Start new GPU entry
				currentGPU = &models.GPU{
					BDF:          pciAddr,
					Manufacturer: "NVIDIA",
				}
				inGPUInfo = true
				continue
			}
		}

		// End of GPU info section (separator line or new section, but not ls lines)
		if inGPUInfo && (strings.HasPrefix(line, "___") || (strings.HasPrefix(line, "***") && !strings.Contains(line, "ls:"))) {
			inGPUInfo = false
			continue
		}

		// Parse GPU fields within information section
		if inGPUInfo && currentGPU != nil && strings.Contains(line, ":") {
			// Split on first colon and trim whitespace/tabs
			parts := strings.SplitN(line, ":", 2)
			if len(parts) != 2 {
				continue
			}

			field := strings.TrimSpace(parts[0])
			value := strings.TrimSpace(parts[1])

			if value == "" {
				continue
			}

			switch field {
			case "Model":
				currentGPU.Model = value
			case "IRQ":
				if irq, err := strconv.Atoi(value); err == nil {
					currentGPU.IRQ = irq
				}
			case "GPU UUID":
				currentGPU.UUID = value
			case "Video BIOS":
				currentGPU.VideoBIOS = value
			case "Bus Type":
				currentGPU.BusType = value
			case "DMA Size":
				currentGPU.DMASize = value
			case "DMA Mask":
				currentGPU.DMAMask = value
			case "Bus Location":
				// BDF already set from path, but verify consistency
				if currentGPU.BDF != value {
					// Use the value from the information section as it's more explicit
					currentGPU.BDF = value
				}
			case "Device Minor":
				if minor, err := strconv.Atoi(value); err == nil {
					currentGPU.DeviceMinor = minor
				}
			case "GPU Excluded":
				// Store as status if "Yes"
				if strings.ToLower(value) == "yes" {
					currentGPU.Status = "Excluded"
				}
			}
		}
	}

	// Save last GPU if exists
	if currentGPU != nil {
		result.Hardware.GPUs = append(result.Hardware.GPUs, *currentGPU)
	}

	applyGPUSerialNumbers(content, result.Hardware.GPUs)

	// Create event for GPU summary
	if len(result.Hardware.GPUs) > 0 {
		result.Events = append(result.Events, models.Event{
			Timestamp:   time.Now(),
			Source:      "NVIDIA Driver",
			EventType:   "GPU Detection",
			Description: "NVIDIA GPUs detected",
			Severity:    models.SeverityInfo,
			RawData:     formatGPUSummary(result.Hardware.GPUs),
		})
	}
}

// parseDriverVersion extracts NVIDIA driver version
func parseDriverVersion(content string, result *models.AnalysisResult) {
	scanner := bufio.NewScanner(strings.NewReader(content))

	for scanner.Scan() {
		line := scanner.Text()

		// Look for NVRM version line
		if strings.Contains(line, "NVRM version:") {
			// Extract version info
			parts := strings.Split(line, "NVRM version:")
			if len(parts) > 1 {
				version := strings.TrimSpace(parts[1])

				result.Events = append(result.Events, models.Event{
					Timestamp:   time.Now(),
					Source:      "NVIDIA Driver",
					EventType:   "Driver Version",
					Description: "NVIDIA driver version detected",
					Severity:    models.SeverityInfo,
					RawData:     version,
				})
				break
			}
		}
	}
}

// formatGPUSummary creates a summary string for GPUs
func formatGPUSummary(gpus []models.GPU) string {
	if len(gpus) == 0 {
		return ""
	}

	var summary strings.Builder
	for i, gpu := range gpus {
		if i > 0 {
			summary.WriteString("; ")
		}
		summary.WriteString(gpu.BDF)
		if gpu.Model != "" {
			summary.WriteString(" (")
			summary.WriteString(gpu.Model)
			summary.WriteString(")")
		}
	}

	return summary.String()
}

func applyGPUSerialNumbers(content string, gpus []models.GPU) {
	if len(gpus) == 0 {
		return
	}

	serialByBDF := parseGPUSerialsFromNvidiaSMI(content)
	if len(serialByBDF) == 0 {
		serialByBDF = parseGPUSerialsFromSummary(content)
	}

	if len(serialByBDF) == 0 {
		return
	}

	for i := range gpus {
		bdf := normalizeGPUAddress(gpus[i].BDF)
		if bdf == "" {
			continue
		}
		if serial, ok := serialByBDF[bdf]; ok && serial != "" {
			gpus[i].SerialNumber = serial
		}
	}
}

func parseGPUSerialsFromNvidiaSMI(content string) map[string]string {
	scanner := bufio.NewScanner(strings.NewReader(content))
	reGPU := regexp.MustCompile(`^GPU\s+([0-9A-F]{8}:[0-9A-F]{2}:[0-9A-F]{2}\.[0-9A-F])$`)

	serialByBDF := make(map[string]string)
	currentBDF := ""

	for scanner.Scan() {
		line := strings.TrimSpace(scanner.Text())
		if line == "" {
			continue
		}

		if matches := reGPU.FindStringSubmatch(line); len(matches) == 2 {
			currentBDF = normalizeGPUAddress(matches[1])
			continue
		}

		if currentBDF == "" {
			continue
		}

		if strings.HasPrefix(line, "Serial Number") {
			parts := strings.SplitN(line, ":", 2)
			if len(parts) != 2 {
				continue
			}
			serial := strings.TrimSpace(parts[1])
			if serial != "" && !strings.EqualFold(serial, "N/A") {
				serialByBDF[currentBDF] = serial
			}
		}
	}

	return serialByBDF
}

func parseGPUSerialsFromSummary(content string) map[string]string {
	scanner := bufio.NewScanner(strings.NewReader(content))

	serialByBDF := make(map[string]string)
	inGPUDetails := false

	for scanner.Scan() {
		line := scanner.Text()
		trimmed := strings.TrimSpace(line)

		if strings.HasPrefix(trimmed, "NVIDIA GPU Details") {
			inGPUDetails = true
		}
		if !inGPUDetails {
			continue
		}
		if strings.HasPrefix(trimmed, "NVIDIA Switch Details") {
			break
		}

		parts := strings.Split(line, "|")
		if len(parts) < 2 {
			continue
		}
		payload := strings.TrimSpace(parts[len(parts)-1])
		if payload == "" {
			continue
		}

		fields := strings.Split(payload, ",")
		if len(fields) < 6 {
			continue
		}

		bdf := normalizeGPUAddress(strings.TrimSpace(fields[4]))
		serial := strings.TrimSpace(fields[5])
		if bdf == "" || serial == "" || strings.EqualFold(serial, "N/A") {
			continue
		}
		serialByBDF[bdf] = serial
	}

	return serialByBDF
}

func normalizeGPUAddress(addr string) string {
	addr = strings.TrimSpace(addr)
	if addr == "" {
		return ""
	}
	parts := strings.Split(addr, ":")
	if len(parts) != 3 {
		return strings.ToLower(addr)
	}

	domain := parts[0]
	bus := parts[1]
	devFn := parts[2]

	devFnParts := strings.Split(devFn, ".")
	if len(devFnParts) != 2 {
		return strings.ToLower(addr)
	}
	device := devFnParts[0]
	fn := devFnParts[1]

	if len(domain) == 8 {
		domain = domain[4:]
	}

	return strings.ToLower(domain + ":" + bus + ":" + device + "." + fn)
}