from migrations.fixtures.delphi_tables.v1.triggers.base_trigger import BaseTrigger


class LinkfireCampaignTrigger(BaseTrigger):
    table = "LinkfireCampaign"
    function_name = "log_linkfire_campaign_changes"

    def on_insert(self):
        return f"""
            IF (({self.__select_campaign(columns='campaign.external_id')}) IS NOT NULL) THEN
                INSERT INTO linkfire_link_campaign(campaign_id, link_id)
                    VALUES (
                        ({self.__select_campaign(columns="campaign_dsp_id(campaign.source, campaign.external_id)")}),
                        ({self.__select_link_id()})
                    )
                    ON CONFLICT DO NOTHING;
            ELSE
                UPDATE "Campaign"
                    SET source = COALESCE(({self.__select_campaign(columns='campaign.source')}), 'dec'),
                        external_id = ({self.__select_campaign(columns='campaign.id')})
                    WHERE id = NEW.campaign_id;
            END IF;
        """

    def on_delete(self):
        return f"""
            DELETE FROM linkfire_link_campaign
                WHERE linkfire_link_campaign.campaign_id = ({
                    self.__select_campaign(columns="campaign_dsp_id(campaign.source, campaign.external_id)", state="OLD")
                })
                AND linkfire_link_campaign.link_id = ({self.__select_link_id(state="OLD")});
            IF NOT EXISTS ({self.__is_links_exists_for_campaigns()}) THEN
                UPDATE "Campaign"
                    SET external_id = NULL,
                        source = (
                            CASE WHEN ({self.__select_campaign(columns='campaign.source', state='OLD')}) in ('PRS') THEN
                                'PRS'
                            ELSE
                                NULL
                            END
                        )
                    WHERE id = OLD.campaign_id AND source in ('dec', 'PRS');
            END IF;
        """

    def __select_campaign(self, columns="campaign.id, campaign.source, campaign.external_id", state="NEW"):
        return f"""
            SELECT {columns}
            FROM "Campaign" as campaign
            WHERE campaign.id = {state}.campaign_id
            LIMIT 1
        """

    def __is_links_exists_for_campaigns(self):
        return f"""
            SELECT 1 FROM "LinkfireCampaign" AS linkfire_campaign WHERE linkfire_campaign.campaign_id = OLD.campaign_id
        """

    def __select_link_id(self, state="NEW"):
        return f"""
            SELECT linkfire.link_id::uuid FROM "Linkfire" linkfire WHERE linkfire.id = {state}.linkfire_id
        """