syntax = "proto3";

package backend_proto;

message Empty {}

// 1-15 reserved for future use; 2047 for errors

message BackendInput {
    reserved 2047;
    oneof value {
        TemplateRequirementsIn template_requirements = 16;
        SchedTimingTodayIn sched_timing_today = 17;

        PlusOneIn plus_one = 2046; // temporary, for testing

    }
}

message BackendOutput {
    oneof value {
        TemplateRequirementsOut template_requirements = 16;
        SchedTimingTodayOut sched_timing_today = 17;

        PlusOneOut plus_one = 2046; // temporary, for testing

        BackendError error = 2047;
    }
}

message BackendError {
    oneof value {
        InvalidInputError invalid_input = 1;
        TemplateParseError template_parse = 2;
    }
}

message InvalidInputError {
    string info = 1;
}

message PlusOneIn {
    int32 num = 1;
}

message PlusOneOut {
    int32 num = 1;
}

message TemplateParseError {
    string info = 1;
}

message TemplateRequirementsIn {
    repeated string template_front = 1;
    map<string, uint32> field_names_to_ordinals = 2;
}

message TemplateRequirementsOut {
    repeated TemplateRequirement requirements = 1;
}

message TemplateRequirement {
    oneof value {
        TemplateRequirementAll all = 1;
        TemplateRequirementAny any = 2;
        Empty none = 3;
    }
}

message TemplateRequirementAll {
    repeated uint32 ords = 1;
}

message TemplateRequirementAny {
    repeated uint32 ords = 1;
}

message SchedTimingTodayIn {
    int64 created = 1;
    int64 now = 2;
    sint32 minutes_west = 3;
    sint32 rollover_hour = 4;
}

message SchedTimingTodayOut {
    uint32 days_elapsed = 1;
    int64 next_day_at = 2;
}