package storage

import (
	"database/sql"
	"errors"
	"strings"
	"time"
)

const logHeaderInsert = "INSERT INTO `logheader` (id,channel,time,status,status_time,title,tag,description) VALUES (?, ?, ?, ?, ?, ?, ?, ?);"
const logHeaderUpdate = "UPDATE `logheader` SET channel=?,time=?,status=?,status_time=?,title=?,tag=?,description=? WHERE id=?;"
const logNicksInsert = "INSERT INTO `lognicks` (log_id,nick) VALUES (?, ?);"
const logNicksDelete = "DELETE FROM `lognicks` WHERE log_id=? AND nick=?;"

// LogHeader is the struct
type LogHeader struct {
	ID          string    `json:"id"`
	Channel     string    `json:"channel"`
	Time        time.Time `json:"time"`
	Status      string    `json:"status"`
	StatusTime  time.Time `json:"statusTime"`
	Title       string    `json:"title"`
	Tag         string    `json:"tag"`
	Description string    `json:"description"`
	Nicks       []string  `json:"nicks"`

	nicksAdded   []string
	nicksRemoved []string
}

// SetStatus changes the value of header.Status and updates
// header.StatusTime.
func (header *LogHeader) SetStatus(value string) {
	header.Status = strings.ToLower(value)
	header.StatusTime = time.Now()
}

// HasNick returns whether a nick exists
func (header *LogHeader) HasNick(nick string) bool {
	for _, existingNick := range header.Nicks {
		if existingNick == nick {
			return true
		}
	}

	return false
}

// AddNick adds a nick to the Nicks array, recording the
// change. If the nick exists, it will not be added, though
// it won't throw an error.
func (header *LogHeader) AddNick(nick string) {
	if !header.HasNick(nick) {
		header.Nicks = append(header.Nicks, nick)
		header.nicksAdded = append(header.nicksAdded, nick)
	}
}

// RemoveNick removes a nick from the Nicks array, recording
// the change.
func (header *LogHeader) RemoveNick(nick string) {
	for i, existingNick := range header.Nicks {
		if existingNick == nick {
			header.Nicks = append(header.Nicks[:i], header.Nicks[i+1:]...)
			header.nicksRemoved = append(header.nicksRemoved, nick)
			return
		}
	}
}

// Insert inserts the LogHeader into the database, as well as all nicks
func (header *LogHeader) Insert(db *sql.DB) error {
	// Insert the header
	result, err := db.Exec(logHeaderInsert, header.ID, header.Channel, header.Time, header.Status, header.StatusTime, header.Title, header.Tag, header.Description)
	if err != nil {
		return err
	}

	// Check if it was actually inserted
	rows, err := result.RowsAffected()
	if err != nil {
		return err
	}
	if rows != 1 {
		return errors.New("storage: No LogHeader inserted")
	}

	// Insert all lognicks
	for _, nick := range header.Nicks {
		_, err := db.Exec(logNicksInsert, header.ID, nick)
		if err != nil {
			return err
		}
	}

	// Clear the nicksAdded and nicksRemoved lists
	header.nicksAdded = nil
	header.nicksRemoved = nil

	// Success
	return nil
}

// Save updates the logheader
func (header *LogHeader) Save(db *sql.DB) error {
	// Insert the header
	_, err := db.Exec(logHeaderUpdate, header.Channel, header.Time, header.Status, header.StatusTime, header.Title, header.Tag, header.Description, header.ID)
	if err != nil {
		return err
	}

	// Delete all removed lognicks
	for _, nick := range header.nicksRemoved {
		_, err := db.Exec(logNicksDelete, header.ID, nick)
		if err != nil {
			return err
		}
	}

	// Insert all new lognicks
	for _, nick := range header.nicksAdded {
		_, err := db.Exec(logNicksInsert, header.ID, nick)
		if err != nil {
			return err
		}
	}

	// Clear the nicksAdded and nicksRemoved lists
	header.nicksAdded = nil
	header.nicksRemoved = nil

	// Success
	return nil
}

// NewLogHeader creates a new LogHeader with an ID based the time and channel
// value. It also sets StatusTime to the current time. It leaves
// Title, Tag and Nicks blank.
func NewLogHeader(logTime time.Time, channel, status string) *LogHeader {
	header := new(LogHeader)
	header.ID = logTime.Format("2006-01-02_150405999_") + channel[1:]
	header.Channel = channel
	header.Time = logTime
	header.Status = status
	header.StatusTime = time.Now()

	return header
}