package exporter

import (
	"encoding/csv"
	"encoding/json"
	"fmt"
	"io"

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

// Exporter handles data export in various formats
type Exporter struct {
	result *models.AnalysisResult
}

// New creates a new exporter
func New(result *models.AnalysisResult) *Exporter {
	return &Exporter{result: result}
}

// ExportCSV exports serial numbers to CSV format
func (e *Exporter) ExportCSV(w io.Writer) error {
	writer := csv.NewWriter(w)
	defer writer.Flush()

	// Header
	if err := writer.Write([]string{"Component", "Serial Number", "Manufacturer", "Part Number"}); err != nil {
		return err
	}

	if e.result == nil {
		return nil
	}

	// FRU data
	for _, fru := range e.result.FRU {
		if fru.SerialNumber == "" {
			continue
		}
		name := fru.ProductName
		if name == "" {
			name = fru.Description
		}
		if err := writer.Write([]string{
			name,
			fru.SerialNumber,
			fru.Manufacturer,
			fru.PartNumber,
		}); err != nil {
			return err
		}
	}

	// Hardware data
	if e.result.Hardware != nil {
		// Memory
		for _, mem := range e.result.Hardware.Memory {
			if mem.SerialNumber == "" {
				continue
			}
			if err := writer.Write([]string{
				fmt.Sprintf("DIMM Slot %d (%s)", mem.Slot, mem.PartNumber),
				mem.SerialNumber,
				mem.Manufacturer,
				mem.PartNumber,
			}); err != nil {
				return err
			}
		}

		// Storage
		for _, stor := range e.result.Hardware.Storage {
			if stor.SerialNumber == "" {
				continue
			}
			if err := writer.Write([]string{
				fmt.Sprintf("%s %s", stor.Type, stor.Model),
				stor.SerialNumber,
				"",
				"",
			}); err != nil {
				return err
			}
		}

		// PCIe devices
		for _, pcie := range e.result.Hardware.PCIeDevices {
			if pcie.SerialNumber == "" {
				continue
			}
			if err := writer.Write([]string{
				fmt.Sprintf("%s (%s)", pcie.DeviceClass, pcie.Slot),
				pcie.SerialNumber,
				"",
				pcie.PartNumber,
			}); err != nil {
				return err
			}
		}
	}

	return nil
}

// ExportJSON exports all data to JSON format
func (e *Exporter) ExportJSON(w io.Writer) error {
	encoder := json.NewEncoder(w)
	encoder.SetIndent("", "  ")
	return encoder.Encode(e.result)
}

// ExportTXT exports a human-readable text report
func (e *Exporter) ExportTXT(w io.Writer) error {
	fmt.Fprintln(w, "LOGPile Analysis Report")
	fmt.Fprintln(w, "========================")
	fmt.Fprintln(w)

	if e.result == nil {
		fmt.Fprintln(w, "No data loaded.")
		return nil
	}

	fmt.Fprintf(w, "File: %s\n\n", e.result.Filename)

	// Hardware summary
	if e.result.Hardware != nil {
		hw := e.result.Hardware

		// Firmware
		if len(hw.Firmware) > 0 {
			fmt.Fprintln(w, "FIRMWARE VERSIONS")
			fmt.Fprintln(w, "-----------------")
			for _, fw := range hw.Firmware {
				fmt.Fprintf(w, "  %s: %s\n", fw.DeviceName, fw.Version)
			}
			fmt.Fprintln(w)
		}

		// CPUs
		if len(hw.CPUs) > 0 {
			fmt.Fprintln(w, "PROCESSORS")
			fmt.Fprintln(w, "----------")
			for _, cpu := range hw.CPUs {
				fmt.Fprintf(w, "  Socket %d: %s\n", cpu.Socket, cpu.Model)
				fmt.Fprintf(w, "            Cores: %d, Threads: %d, Freq: %d MHz (Turbo: %d MHz)\n",
					cpu.Cores, cpu.Threads, cpu.FrequencyMHz, cpu.MaxFreqMHz)
				fmt.Fprintf(w, "            TDP: %dW, L3 Cache: %d KB\n", cpu.TDP, cpu.L3CacheKB)
			}
			fmt.Fprintln(w)
		}

		// Memory
		if len(hw.Memory) > 0 {
			fmt.Fprintln(w, "MEMORY")
			fmt.Fprintln(w, "------")
			totalMB := 0
			for _, mem := range hw.Memory {
				totalMB += mem.SizeMB
			}
			fmt.Fprintf(w, "  Total: %d GB (%d DIMMs)\n", totalMB/1024, len(hw.Memory))
			fmt.Fprintf(w, "  Type: %s @ %d MHz\n", hw.Memory[0].Type, hw.Memory[0].CurrentSpeedMHz)
			fmt.Fprintf(w, "  Manufacturer: %s\n", hw.Memory[0].Manufacturer)
			fmt.Fprintln(w)
		}

		// Storage
		if len(hw.Storage) > 0 {
			fmt.Fprintln(w, "STORAGE")
			fmt.Fprintln(w, "-------")
			for _, stor := range hw.Storage {
				fmt.Fprintf(w, "  %s: %s (%d GB) - S/N: %s\n",
					stor.Slot, stor.Model, stor.SizeGB, stor.SerialNumber)
			}
			fmt.Fprintln(w)
		}

		// PCIe
		if len(hw.PCIeDevices) > 0 {
			fmt.Fprintln(w, "PCIE DEVICES")
			fmt.Fprintln(w, "------------")
			for _, pcie := range hw.PCIeDevices {
				fmt.Fprintf(w, "  %s: %s (x%d %s)\n",
					pcie.Slot, pcie.DeviceClass, pcie.LinkWidth, pcie.LinkSpeed)
				if pcie.SerialNumber != "" {
					fmt.Fprintf(w, "          S/N: %s\n", pcie.SerialNumber)
				}
				if len(pcie.MACAddresses) > 0 {
					fmt.Fprintf(w, "          MACs: %v\n", pcie.MACAddresses)
				}
			}
			fmt.Fprintln(w)
		}
	}

	// Sensors summary
	if len(e.result.Sensors) > 0 {
		fmt.Fprintln(w, "SENSOR READINGS")
		fmt.Fprintln(w, "---------------")

		// Group by type
		byType := make(map[string][]models.SensorReading)
		for _, s := range e.result.Sensors {
			byType[s.Type] = append(byType[s.Type], s)
		}

		for stype, sensors := range byType {
			fmt.Fprintf(w, "\n  %s:\n", stype)
			for _, s := range sensors {
				if s.Value != 0 {
					fmt.Fprintf(w, "    %s: %.0f %s [%s]\n", s.Name, s.Value, s.Unit, s.Status)
				} else if s.RawValue != "" {
					fmt.Fprintf(w, "    %s: %s [%s]\n", s.Name, s.RawValue, s.Status)
				}
			}
		}
		fmt.Fprintln(w)
	}

	// FRU summary
	if len(e.result.FRU) > 0 {
		fmt.Fprintln(w, "FRU COMPONENTS")
		fmt.Fprintln(w, "--------------")
		for _, fru := range e.result.FRU {
			name := fru.ProductName
			if name == "" {
				name = fru.Description
			}
			fmt.Fprintf(w, "  %s\n", name)
			if fru.SerialNumber != "" {
				fmt.Fprintf(w, "    Serial: %s\n", fru.SerialNumber)
			}
			if fru.Manufacturer != "" {
				fmt.Fprintf(w, "    Manufacturer: %s\n", fru.Manufacturer)
			}
		}
		fmt.Fprintln(w)
	}

	// Events summary
	fmt.Fprintf(w, "EVENTS: %d total\n", len(e.result.Events))
	var critical, warning, info int
	for _, ev := range e.result.Events {
		switch ev.Severity {
		case models.SeverityCritical:
			critical++
		case models.SeverityWarning:
			warning++
		case models.SeverityInfo:
			info++
		}
	}
	fmt.Fprintf(w, "  Critical: %d\n", critical)
	fmt.Fprintf(w, "  Warning:  %d\n", warning)
	fmt.Fprintf(w, "  Info:     %d\n", info)

	return nil
}