#include "parser.h"
#include "SolsNode.h"

#include "../include/estr.h"

ResultType(SolsParser, charptr) createSolsParser(SolsTokens* input) {
    ResultType(SolsNode, charptr) node = createSolsNode(SNT_ROOT);
    if (node.error) {
        Estr str = CREATE_ESTR(node.as.error);
        APPEND_ESTR(str, " (in createSolsParser() function)");
    }
    SolsParser parser = {
        .input = input,
        .current = 0,
        .output = node.as.success 
    };
    parser.currentParent = &parser.output;
    return Success(SolsParser, charptr, parser);
}

ResultType(Nothing, charptr) parse(SolsParser* parser) {
    return Error(Nothing, charptr, "Work in progress");
}

ResultType(SolsToken, Nothing) parserPeek(SolsParser* parser, size_t ahead) {
    if (parser->input == NULL) {
        return Error(SolsToken, Nothing, {});
    }
    if (parser->current + ahead - 1 >= parser->input->count) {
        return Error(SolsToken, Nothing, {});
    } 
    return Success(SolsToken, Nothing, parser->input->at[parser->current + ahead - 1]);
}

ResultType(SolsToken, Nothing) parserConsume(SolsParser* parser) {
    if (parser->input == NULL) {
        return Error(SolsToken, Nothing, {});
    }
    if (parser->current + 1 >= parser->input->count) {
        return Error(SolsToken, Nothing, {});
    } 
    return Success(SolsToken, Nothing, parser->input->at[parser->current ++]);
}