package main

import (
	"context"
	"ersteller-lib"
	"github.com/joho/godotenv"
	"os"
)

func main() {
	err := godotenv.Load()
	if err != nil {
		ersteller_lib.LogError("Error loading .env file: %v", err)
		panic(err)
	}
	dbUrl := os.Getenv("DATABASE_URL")
	connpool, err := ersteller_lib.CreatePostgresConnpool(dbUrl)
	if err != nil {
		ersteller_lib.LogError("Failed to create connection pool: %v", err)
		panic(err)
	}
	// https://medium.com/israeli-tech-radar/postgresql-trigger-based-audit-log-fd9d9d5e412c
	sql := `
CREATE TABLE IF NOT EXISTS audit_log (
    id serial PRIMARY KEY,
    table_name TEXT,
    record_id TEXT,
    operation_type TEXT,
    changed_at TIMESTAMP DEFAULT now(),
    changed_by TEXT,
    original_values jsonb,
    new_values jsonb
);

CREATE OR REPLACE FUNCTION audit_trigger() RETURNS TRIGGER AS $$
DECLARE
    new_data jsonb;
    old_data jsonb;
    key text;
    new_values jsonb;
    old_values jsonb;
    user_id text;
BEGIN

    user_id := current_setting('audit.user_id', true);

    IF user_id IS NULL THEN
        user_id := current_user;
    END IF;

    new_values := '{}';
    old_values := '{}';

    IF TG_OP = 'INSERT' THEN
        new_data := to_jsonb(NEW);
        new_values := new_data;

    ELSIF TG_OP = 'UPDATE' THEN
        new_data := to_jsonb(NEW);
        old_data := to_jsonb(OLD);

        FOR key IN SELECT jsonb_object_keys(new_data) INTERSECT SELECT jsonb_object_keys(old_data)
        LOOP
            IF new_data ->> key != old_data ->> key THEN
                new_values := new_values || jsonb_build_object(key, new_data ->> key);
                old_values := old_values || jsonb_build_object(key, old_data ->> key);
            END IF;
        END LOOP;

    ELSIF TG_OP = 'DELETE' THEN
        old_data := to_jsonb(OLD);
        old_values := old_data;

        FOR key IN SELECT jsonb_object_keys(old_data)
        LOOP
            old_values := old_values || jsonb_build_object(key, old_data ->> key);
        END LOOP;

    END IF;

    IF TG_OP = 'INSERT' OR TG_OP = 'UPDATE' THEN
        INSERT INTO audit_log (table_name, record_id, operation_type, changed_by, original_values, new_values)
        VALUES (TG_TABLE_NAME, NEW.id, TG_OP, user_id, old_values, new_values);

        RETURN NEW;
    ELSE
        INSERT INTO audit_log (table_name, record_id, operation_type, changed_by, original_values, new_values)
        VALUES (TG_TABLE_NAME, OLD.id, TG_OP, user_id, old_values, new_values);

        RETURN OLD;
    END IF;
END;
$$ LANGUAGE plpgsql;
   

CREATE OR REPLACE TRIGGER audit_log_trigger
    BEFORE INSERT OR UPDATE OR DELETE 
 ON public."marketDataLead"
    FOR EACH ROW
    EXECUTE FUNCTION audit_trigger();
   
CREATE OR REPLACE TRIGGER audit_log_trigger
    BEFORE INSERT OR UPDATE OR DELETE 
 ON public.group
    FOR EACH ROW
    EXECUTE FUNCTION audit_trigger(); 


CREATE OR REPLACE TRIGGER audit_log_trigger
    BEFORE INSERT OR UPDATE OR DELETE 
 ON public."groupMembership"
    FOR EACH ROW
    EXECUTE FUNCTION audit_trigger();


CREATE OR REPLACE TRIGGER audit_log_trigger
    BEFORE INSERT OR UPDATE OR DELETE 
 ON public."marketDataLeadNote"
    FOR EACH ROW
    EXECUTE FUNCTION audit_trigger();

CREATE OR REPLACE TRIGGER audit_log_trigger
    BEFORE INSERT OR UPDATE OR DELETE 
 ON public.settings
    FOR EACH ROW
    EXECUTE FUNCTION audit_trigger();

CREATE OR REPLACE TRIGGER audit_log_trigger
    BEFORE INSERT OR UPDATE OR DELETE 
 ON public.user
    FOR EACH ROW
    EXECUTE FUNCTION audit_trigger();
`
	_, err = connpool.Exec(context.Background(), sql)
	if err != nil {
		ersteller_lib.LogError("Failed to create audit log table: %v", err)
		panic(err)
	}
	println("Created audit log table")
}