import mysql.connector as mariadb
from Entities import(
  Mailbox,MailboxException,QuarMail,
  QuarMailException,Attachment,
  AttachmentException,URI,URIException
)
from GulagUtils import whoami

class GulagDBException(Exception):
  message = None
  def __init__(self,message):
    self.message = str(message)

class GulagDB:
  conn = None
  uri_prefixes = None

  def __init__(self, args, uri_prefixes):
    try:
      if 'unix_socket' in args:
        self.conn = mariadb.connect(
          unix_socket=args['unix_socket'],
          user=args['user'],
          password=args['password'],
          database=args['name'],
          autocommit=True
        )
      else:
        self.conn = mariadb.connect(
          host=args['server'],
          user=args['user'],
          password=args['password'],
          database=args['name'],
          autocommit=True
        )
      self.uri_prefixes = uri_prefixes
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def close(self):
    self.conn.close()
 
  def get_fields(self,table_name):
    try:
      cursor = self.conn.cursor()
      query = "describe " + str(table_name) + ";"
      cursor.execute(query)
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self) 
          + "describe " + table_name + " failed!"
        )
      desc = cursor.description
      cursor.close()
      results = {}
      for tuple in data:
        for (name, value) in zip(desc, tuple):
          if(name[0] == "Field"):
            results[value] = True
      return results
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def get_limit_clause(self,args):
    if('query_offset' in args and 'query_limit' in args): 
      try:
        int(args['query_offset'])
      except ValueError:
        raise GulagDBException(whoami(self) + "query_offset must be numeric!")
      try:
        int(args['query_limit'])
      except ValueError:
        raise GulagDBException(whoami(self) + "query_limit must be numeric!")
      return "limit "+args['query_offset']+","+args['query_limit']
    elif('query_offset' in args and 'query_limit' not in args):
      raise GulagDBException(whois(self) + 
        "query_offset without query_limit is useless!"
      )
    elif('query_limit' in args and 'query_offset' not in args):
      try:
        int(args['query_limit'])
      except ValueError:
        raise GulagDBException(whoami(self) + "query_limit must be numeric!")
      return "limit " + args['query_limit']
    else:
      return ""

  def get_where_clause(self,args):
    where_clause = ""
    cnt = 0
    for arg in args:
      if(arg == 'query_offset' or arg == 'query_limit'
         or arg == 'sort_index' or arg == 'sort_order'):
        continue
      if(cnt == 0):
        where_clause += "where " + arg + "='" + args[arg] + "' "
      else:
        where_clause += "and " + arg + "='" + args[arg] + "' "
      cnt += 1
    return where_clause

  def parse_filters(self,filters):
    # TODO
    # {"groupOp":"AND","rules":[{"field":"Customer","op":"eq","data":"eosp"}]}
    return True

  def get_mailboxes(self):
    try:
      cursor = self.conn.cursor()
      cursor.execute("select * from Mailboxes;")
      results = []
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self) + "No mailboxes found in DB!")
      desc = cursor.description
      for tuple in data:
        dict = {}
        for (name, value) in zip(desc, tuple):
          dict[name[0]] = value
        dict['href'] = self.uri_prefixes['mailboxes'] + dict['email_address']
        try:
          results.append(Mailbox(dict).__dict__)
        except MailboxException as e:
          print("MailboxException: " + e.message)
          continue
      return results
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def get_mailbox(self,mailbox_id):
    try:
      cursor = self.conn.cursor()
      cursor.execute(
        "select * from Mailboxes where email_address='" + mailbox_id + "' limit 1;"
      )
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self)
          + "Mailbox '" + mailbox_id + "' does not exist!"
        )
      desc = cursor.description
      tuple = data[0]
      dict = {}
      for (name, value) in zip(desc, tuple):
        dict[name[0]] = value
      dict['href'] = self.uri_prefixes['mailboxes'] + dict['email_address']
      try:
        return Mailbox(dict).__dict__
      except MailboxException as e:
        raise GulagDBException(whoami(self) + e.message) from e
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e
 
  def add_quarmail(self, quarmail):
    try:
      cursor = self.conn.cursor()
      cursor.execute("insert into QuarMails " +
          "(mx_queue_id,env_from,env_rcpt,"+
          "hdr_cf,hdr_from,hdr_subject,"+
          "hdr_msgid,hdr_date,cf_meta,"+
          "mailbox_id,imap_uid,msg_size) " +
        "values (%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s,%s)",
        (quarmail['mx_queue_id'],quarmail['env_from'],quarmail['env_rcpt'],
         quarmail['hdr_cf'],quarmail['hdr_from'],quarmail['hdr_subject'],
         quarmail['hdr_msgid'],quarmail['hdr_date'],quarmail['cf_meta'],
         quarmail['mailbox_id'],quarmail['imap_uid'],quarmail['msg_size']
        )
      )
      id = cursor.lastrowid
      cursor.close()
      return id
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + (e)) from e

  def del_quarmail(self, id):
    try:
      cursor = self.conn.cursor()
      cursor.execute("delete from QuarMails where id=%s;", (id))
      cursor.close()
      return True
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def get_quarmails(self,args):
    try: 
      cursor = self.conn.cursor()
      query = "select *,(select count(*) from QuarMail2Attachment"
      query += " where QuarMails.id=QuarMail2Attachment.quarmail_id) as attach_count"
      query += " from QuarMails " + self.get_where_clause(args)
      query += " " + self.get_limit_clause(args) + " ;"
      cursor.execute(query)
      results = []
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self) + "No QuarMails found in DB!")
      desc = cursor.description
      cursor.close()
      for tuple in data:
        dict = {}
        for (name, value) in zip(desc, tuple):
          if(name[0] == 'ctime'):
            dict[name[0]] = value.strftime('%Y-%m-%d %H:%M:%S')
          else:
            dict[name[0]] = value
        dict['href'] = self.uri_prefixes['quarmails'] + str(dict['id'])
        results.append(QuarMail(dict).__dict__)
      return results
    except GulagDBException as e:
      raise GulagDBException(whoami(self) + e.message) from e
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def get_quarmail(self,args):
    try:
      cursor = self.conn.cursor()
      # TODO: build SQL query by args
      #query = "select * from QuarMails where id='" + args['id'] + "';"
      query = "select *,(select count(*) from QuarMail2Attachment"
      query += " where QuarMails.id=QuarMail2Attachment.quarmail_id) as attach_count"
      query += " from QuarMails where QuarMails.id="+ str(args['id']) +";"
      cursor.execute(query)
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self)
          + "Quarmail with id '"+ str(args['id']) + "' does not exist!"
        )
      desc = cursor.description
      cursor.close()
      tuple = data[0]
      dict = {}
      for (name, value) in zip(desc, tuple):
        if(name[0] == 'ctime'):
          dict[name[0]] = value.strftime('%Y-%m-%d %H:%M:%S')
        else:
          dict[name[0]] = value
      dict['href'] = self.uri_prefixes['quarmails'] + str(dict['id'])
#      try:
#        dict['attachments'] = self.get_attachments_by_quarmail(args['id'])
#      except GulagDBException as e:
#        pass
      return QuarMail(dict).__dict__
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def get_deprecated_mails(self,retention_period):
    try:
      cursor = self.conn.cursor()
      query = "select ctime,mailbox_id,imap_uid from QuarMails"
      query += " where ctime < date_sub(NOW(), INTERVAL "+ str(retention_period) +");"
      cursor.execute(query)
      results = []
      data = cursor.fetchall()
      if not data:
        return results
      desc = cursor.description
      for tuple in data:
        dict = {}
        for (name, value) in zip(desc, tuple):
          dict[name[0]] = value
        results.append(dict)
      return results
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def add_attachment(self, attach):
    try:
      cursor = self.conn.cursor()
      cursor.execute("insert into Attachments " +
        "(filename, content_type, content_encoding) values (%s,%s,%s)",
        (attach['filename'], attach['content_type'], attach['content_encoding'])
      )
      return cursor.lastrowid
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e
 
  def get_attachments(self):
    try:
      query = "select Attachments.*,QuarMails.mailbox_id,QuarMails.imap_uid"
      query += " from QuarMail2Attachment" 
      query += " left join QuarMails ON QuarMails.id = QuarMail2Attachment.quarmail_id"
      query += " left join Attachments ON Attachments.id = QuarMail2Attachment.attachment_id"
      query += " group by id;"
      cursor = self.conn.cursor()
      cursor.execute(query)
      results = []
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self) + "No attachments found!")
      desc = cursor.description
      for tuple in data:
        dict = {}
        for (name, value) in zip(desc, tuple):
          dict[name[0]] = value
        dict['href'] = self.uri_prefixes['attachments'] + str(dict['id'])
        results.append(Attachment(dict).__dict__)
      return results
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e
  
  def get_attachment(self, args):
    try:
      cursor = self.conn.cursor()
      query = "select Attachments.*,QuarMails.mailbox_id,QuarMails.imap_uid"
      query += " from QuarMail2Attachment" 
      query += " left join QuarMails ON QuarMails.id = QuarMail2Attachment.quarmail_id"
      query += " left join Attachments ON Attachments.id = QuarMail2Attachment.attachment_id"
      query += " where id=" + str(args['id']) + ";"
      cursor.execute(query)
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self)
          + "Attachment("+ str(args['id']) +") does not exist!"
        )
      desc = cursor.description
      tuple = data[0]
      dict = {}
      for (name, value) in zip(desc, tuple):
        dict[name[0]] = value
      dict['href'] = self.uri_prefixes['attachments'] + str(dict['id'])
      return Attachment(dict).__dict__
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e
  
  def get_quarmail_attachments(self,quarmail_id):
    try:
      query = "select Attachments.*,QuarMails.mailbox_id,QuarMails.imap_uid"
      query += " from QuarMail2Attachment"
      query += " left join QuarMails ON QuarMails.id = QuarMail2Attachment.quarmail_id"
      query += " left join Attachments ON Attachments.id = QuarMail2Attachment.attachment_id"
      query += " where QuarMails.id = " + str(quarmail_id) + ";"
      cursor = self.conn.cursor()
      cursor.execute(query)
      results = []
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self)
          + "QuarMail("+ str(quarmail_id) +") has no attachments!"
        )
      desc = cursor.description
      for tuple in data:
        dict = {}
        for (name, value) in zip(desc, tuple):
          dict[name[0]] = value
        dict['href'] = self.uri_prefixes['quarmails'] + str(quarmail_id) 
        dict['href'] += "/attachments/" + str(dict['id'])
        results.append(Attachment(dict).__dict__)
      return results
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def get_quarmail_attachment(self,quarmail_id,attachment_id):
    try:
      query = "select Attachments.*,QuarMails.mailbox_id,QuarMails.imap_uid"
      query += " from QuarMail2Attachment"
      query += " left join QuarMails ON QuarMails.id = QuarMail2Attachment.quarmail_id"
      query += " left join Attachments ON Attachments.id = QuarMail2Attachment.attachment_id"
      query += " where QuarMails.id = " + str(quarmail_id)
      query += " and Attachments.id = " + str(attachment_id) + ";"
      cursor = self.conn.cursor()
      cursor.execute(query)
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self) + "QuarMail("+ str(quarmail_id) +") "
          + "has no attachment (" + str(attachment_id) + ")!"
        )
      desc = cursor.description
      tuple = data[0]
      dict = {}
      for (name, value) in zip(desc, tuple):
        dict[name[0]] = value
      dict['href'] = self.uri_prefixes['quarmails'] + str(quarmail_id)
      dict['href'] += "/attachments/" + str(dict['id'])
      return Attachment(dict).__dict__
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  
  def quarmail2attachment(self,quarmail_id,attachment_id):
    try:
      cursor = self.conn.cursor()
      cursor.execute("insert into QuarMail2Attachment " +
        "(quarmail_id, attachment_id) values (%s,%s)",
        (quarmail_id, attachment_id)
      )
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def add_uri(self,args):
    try:
      cursor = self.conn.cursor()
      cursor.execute("insert into URIs " +
        "(uri, fqdn) values (%s,%s)",
        (args['uri'], args['fqdn'])
      )
      return cursor.lastrowid
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e

  def del_uri(self,uri_id):
    try:
      cursor = self.conn.cursor()
      cursor.execute(
        "delete from URIs where uri_id=" +  uri_id + ";"
      )
      return cursor.lastrowid
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e


  def quarmail2uri(self,quarmail_id,uri_id):
    try:
      cursor = self.conn.cursor()
      cursor.execute("insert into QuarMail2URI " +
        "(quarmail_id, uri_id) values (%s,%s)",
        (quarmail_id, uri_id)
      )
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e
    
  def get_quarmail_uris(self,quarmail_id):
    try:
      query = "select URIs.*"
      query += " from QuarMail2URI"
      query += " left join QuarMails ON QuarMails.id = QuarMail2URI.quarmail_id"
      query += " left join URIs ON URIs.id = QuarMail2URI.uri_id"
      query += " where QuarMails.id = " + str(quarmail_id) + ";"
      cursor = self.conn.cursor()
      cursor.execute(query)
      results = []
      data = cursor.fetchall()
      if not data:
        raise GulagDBException(whoami(self)
          + "QuarMail("+ str(quarmail_id) +") has no uris!"
        )
      desc = cursor.description
      for tuple in data:
        dict = {}
        for (name, value) in zip(desc, tuple):
          dict[name[0]] = value
        dict['href'] = self.uri_prefixes['quarmails'] + str(quarmail_id)
        dict['href'] += "/uris/" + str(dict['id'])
        results.append(URI(dict).__dict__)
      return results
    except mariadb.Error as e:
      raise GulagDBException(whoami(self) + str(e)) from e