#include <stdio.h>

#include "apfl.h"

#define POSFMT "%d:%d"
#define POSARGS error.position.line, error.position.col
#define POS2ARGS error.position2.line, error.position2.col

const char *
apfl_error_type_name(enum apfl_error_type type)
{
    switch (type) {
    case APFL_ERR_MALLOC_FAILED:
        return "APFL_ERR_MALLOC_FAILED";
    case APFL_ERR_INPUT_ERROR:
        return "APFL_ERR_INPUT_ERROR";
    case APFL_ERR_UNEXPECTED_EOF:
        return "APFL_ERR_UNEXPECTED_EOF";
    case APFL_ERR_EXPECTED_EQ_AFTER_COLON:
        return "APFL_ERR_EXPECTED_EQ_AFTER_COLON";
    case APFL_ERR_UNEXPECTED_BYTE:
        return "APFL_ERR_UNEXPECTED_BYTE";
    case APFL_ERR_UNEXPECTED_BYTE_IN_NUMBER:
        return "APFL_ERR_UNEXPECTED_BYTE_IN_NUMBER";
    case APFL_ERR_EXPECTED_DIGIT:
        return "APFL_ERR_EXPECTED_DIGIT";
    case APFL_ERR_EXPECTED_HEX_IN_HEX_ESCAPE:
        return "APFL_ERR_EXPECTED_HEX_IN_HEX_ESCAPE";
    case APFL_ERR_INVALID_ESCAPE_SEQUENCE:
        return "APFL_ERR_INVALID_ESCAPE_SEQUENCE";
    case APFL_ERR_NO_LINEBREAK_AFTER_CONTINUE_LINE:
        return "APFL_ERR_NO_LINEBREAK_AFTER_CONTINUE_LINE";
    case APFL_ERR_UNEXPECTED_TOKEN:
        return "APFL_ERR_UNEXPECTED_TOKEN";
    case APFL_ERR_MISMATCHING_CLOSING_BRACKET:
        return "APFL_ERR_MISMATCHING_CLOSING_BRACKET";
    case APFL_ERR_UNEXPECTED_EOF_AFTER_TOKEN:
        return "APFL_ERR_UNEXPECTED_EOF_AFTER_TOKEN";
    case APFL_ERR_STATEMENTS_BEFORE_PARAMETERS:
        return "APFL_ERR_STATEMENTS_BEFORE_PARAMETERS";
    case APFL_ERR_EMPTY_ASSIGNMENT_BEFORE_PARAMETERS:
        return "APFL_ERR_EMPTY_ASSIGNMENT_BEFORE_PARAMETERS";
    case APFL_ERR_UNEXPECTED_EXPRESSION:
        return "APFL_ERR_UNEXPECTED_EXPRESSION";
    case APFL_ERR_INVALID_ASSIGNMENT_LHS:
        return "APFL_ERR_INVALID_ASSIGNMENT_LHS";
    case APFL_ERR_EMPTY_ASSIGNMENT:
        return "APFL_ERR_EMPTY_ASSIGNMENT";
    case APFL_ERR_ONLY_ONE_EXPAND_ALLOWED:
        return "APFL_ERR_ONLY_ONE_EXPAND_ALLOWED";
    case APFL_ERR_UNEXPECTED_CONSTANT_IN_MEMBER_ACCESS:
        return "APFL_ERR_UNEXPECTED_CONSTANT_IN_MEMBER_ACCESS";
    case APFL_ERR_UNEXPECTED_EXPR_IN_MEMBER_ACCESS:
        return "APFL_ERR_UNEXPECTED_EXPR_IN_MEMBER_ACCESS";
    }

    return "<unknown error>";
}

void
apfl_error_print(struct apfl_error error, FILE *file)
{
    switch (error.type) {
    case APFL_ERR_MALLOC_FAILED:
        fprintf(file, "Could not allocate memory\n");
        return;
    case APFL_ERR_INPUT_ERROR:
        fprintf(file, "Input error while parsing\n");
        return;
    case APFL_ERR_UNEXPECTED_EOF:
        fprintf(file, "Unexpected end of file\n");
        return;
    case APFL_ERR_EXPECTED_EQ_AFTER_COLON:
        fprintf(file, "Expected '=' after ':' at " POSFMT "\n", POSARGS);
        return;
    case APFL_ERR_UNEXPECTED_BYTE:
        fprintf(file, "Unexpected byte '%c' (0x%X) at " POSFMT "\n", error.byte, (unsigned)error.byte, POSARGS);
        return;
    case APFL_ERR_UNEXPECTED_BYTE_IN_NUMBER:
        fprintf(file, "Unexpected byte '%c' while parsing number at " POSFMT "\n", error.byte, POSARGS);
        return;
    case APFL_ERR_EXPECTED_DIGIT:
        fprintf(file, "Expected a digit at " POSFMT "\n", POSARGS);
        return;
    case APFL_ERR_EXPECTED_HEX_IN_HEX_ESCAPE:
        fprintf(file, "Expected a hex-digit in hex escape at " POSFMT "\n", POSARGS);
        return;
    case APFL_ERR_INVALID_ESCAPE_SEQUENCE:
        fprintf(file, "Invalid escape sequence \\%c at " POSFMT "\n", error.byte, POSARGS);
        return;
    case APFL_ERR_NO_LINEBREAK_AFTER_CONTINUE_LINE:
        fprintf(file, "No line break (after optional comments) after \\ at " POSFMT "\n", POSARGS);
        return;
    case APFL_ERR_UNEXPECTED_TOKEN:
        fprintf(file, "Unexpected `%s` token at " POSFMT "\n", apfl_token_type_name(error.token_type), POSARGS);
        return;
    case APFL_ERR_MISMATCHING_CLOSING_BRACKET:
        fprintf(
            file,
            "Closing `%s` token at " POSFMT " does not match opening `%s` at " POSFMT "\n",
            apfl_token_type_name(error.token_type),
            POSARGS,
            apfl_token_type_name(error.token_type2),
            POS2ARGS
        );
        return;
    case APFL_ERR_UNEXPECTED_EOF_AFTER_TOKEN:
        fprintf(
            file,
            "Unexpected end of file after `%s` token at " POSFMT "\n",
            apfl_token_type_name(error.token_type),
            POSARGS
        );
        return;
    case APFL_ERR_STATEMENTS_BEFORE_PARAMETERS:
        fprintf(
            file,
            "Unexpected statements before parameters near " POSFMT "\n",
            POSARGS
        );
        return;
    case APFL_ERR_EMPTY_ASSIGNMENT_BEFORE_PARAMETERS:
        fprintf(
            file,
            "Unexpected empty assignment before parameters near " POSFMT "\n",
            POSARGS
        );
        return;
    case APFL_ERR_UNEXPECTED_EXPRESSION:
        fprintf(
            file,
            "Unexpected expression near " POSFMT "\n",
            POSARGS
        );
        return;
    case APFL_ERR_INVALID_ASSIGNMENT_LHS:
        fprintf(
            file,
            "Invalid left hand side of assignment near " POSFMT "\n",
            POSARGS
        );
        return;
    case APFL_ERR_EMPTY_ASSIGNMENT:
        fprintf(
            file,
            "Empty assignment at " POSFMT "\n",
            POSARGS
        );
        return;
    case APFL_ERR_ONLY_ONE_EXPAND_ALLOWED:
        fprintf(
            file,
            "Only one expansion (~) is allowed per level, near " POSFMT "\n",
            POSARGS
        );
        break;
    case APFL_ERR_UNEXPECTED_CONSTANT_IN_MEMBER_ACCESS:
        fprintf(
            file,
            "Unexpected constant in member access near " POSFMT "\n",
            POSARGS
        );
        break;
    case APFL_ERR_UNEXPECTED_EXPR_IN_MEMBER_ACCESS:
        fprintf(
            file,
            "Unexpected expression in member access near " POSFMT "\n",
            POSARGS
        );
        break;
    }

    fprintf(file, "Unknown error %d\n", (int)error.type);
}

struct apfl_error
apfl_error_simple(enum apfl_error_type type)
{
    return (struct apfl_error) { .type = type };
}

bool
apfl_error_is_fatal_type(enum apfl_error_type type)
{
    switch (type) {
    case APFL_ERR_MALLOC_FAILED:
    case APFL_ERR_INPUT_ERROR:
        return true;
    default:
        return false;
    }
}