package mailq

import (
	"encoding/json"
	"fmt"
	"io"
	"strings"
	"text/tabwriter"
)

const SortableDateFormat = "2006-01-02 15:04:05"

func (m QEntry) String() string {
	var recipientSuffix string
	if len(m.Recipients) > 1 {
		recipientSuffix = ",..."
	}
	return fmt.Sprintf("[%s] %s <%s> -> {%d}<%s>%s (%s, %d bytes)", m.Date.Format(SortableDateFormat), m.Id, m.Sender, len(m.Recipients), m.Recipients[0], recipientSuffix, m.Status, m.Size)
}

func (m QEntry) MachineReadableString() string {
	return fmt.Sprintf("%s_%s_%s_%d_%s_%s_%s", m.Id, m.Status, m.Date.Format(SortableDateFormat), m.Size, m.Sender, m.Reason, strings.Join(m.Recipients, ","))
}

func (m QEntry) DetailedString() string {
	var reasonStr string
	if m.Reason == "" {
		reasonStr = "-/-"
	}
	return fmt.Sprintf("Id: %s\nDate: %s\nStatus: %s\nReason: %s\nSize: %d\nSender: %s\nRecipients: {%d} %s", m.Id, m.Date.Format(SortableDateFormat), m.Status, reasonStr, m.Size, m.Sender, len(m.Recipients), strings.Join(m.Recipients, ", "))
}

func (queue MailQ) WriteMachineReadable(writer io.Writer) {
	for _, entry := range queue.Entries {
		fmt.Fprintf(writer, "%s\n", entry.MachineReadableString())
	}
}

func (queue MailQ) WriteHumanReadable(writer io.Writer) {
	queue.WriteSummary(writer)
	if len(queue.Entries) != 0 {
		fmt.Fprintf(writer, "\n")
		tabWriter := tabwriter.NewWriter(writer, 2, 2, 1, ' ', tabwriter.TabIndent)
		fmt.Fprintf(tabWriter, "| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| %s\t| \n", "Date", "Id", "Status", "Size", "Sender", "#", "First Recipient", "Reason")
		for _, entry := range queue.Entries {
			_, writeError := fmt.Fprintf(tabWriter, "| %s\t| %s\t| %s\t| %d\t| %s\t| {%d}\t| %s\t| %s\t| \n", entry.Date.Format(SortableDateFormat), entry.Id, entry.Status, entry.Size, entry.Sender, len(entry.Recipients), entry.Recipients[0], entry.Reason)
			if writeError != nil {
				// A writeError is expected once the reader was closed
				break
			}
		}
		tabWriter.Flush()
	}
}

func (queue MailQ) WriteSummary(writer io.Writer) {
	if len(queue.Entries) == 0 {
		fmt.Fprintf(writer, "Mail queue is empty\n")
	} else {
		fmt.Fprintf(writer, "%d entries total (%d active, %d deferred, %d on hold)\n", len(queue.Entries), queue.NumActive, queue.NumDeferred, queue.NumHold)
	}
}

func (queue MailQ) WriteJSON(writer io.Writer) {
	bytes, err := json.Marshal(queue)
	if err != nil {
		fmt.Fprintf(writer, "Error encoding queue to JSON: %s\n", err.Error())
	} else {
		fmt.Fprintf(writer, "%s", bytes)
	}
}