#include "strops.h"
#include <stdlib.h>
#include <assert.h>
#include <stdio.h>

/* Function template
char* strops_(const char* string) {
    char* result = strops_copy(string);
    return result;
}
*/

ull_t strops_length(const char* string) {
    if (!string) {
        return 0;
    }

    ull_t string_length = 0;
    while(string[string_length] != '\0') {
        string_length++;
    }

    return string_length;
}

char* strops_copy(const char* string) {
    if (!string) {
        return 0;
    }
    ull_t length = strops_length(string);
    if (length == 0) {
        return 0;
    }
    char* result = malloc(length);

    ull_t i;
    for(i = 0; i < length; i++) {
        result[i] = string[i];
    }
    result[i] = '\0';

    return result;
}

char* strops_copy_amount(const char* string, ull_t amount) {
    if (!string) {
        return 0;
    }
    if (amount > strops_length(string)) {
        return 0;
    }
    char* result = malloc(amount);

    ull_t i;
    for(i = 0; i < amount; i++) {
        result[i] = string[i];
    }
    result[i] = '\0';

    return result;
}

ull_t strops_first_pos_of_char(const char* string, char char_to_search) {
    ull_t i;
    for (i = 0; string[i] != char_to_search; i++) {}
    return i;
}

ull_t strops_first_pos_of_string(const char* string, const char* string_to_search) {
    bool_t contains_string;
    ull_t sts_length = strops_length(string_to_search);
    ull_t l = strops_length(string) - sts_length + 1;
    ull_t i, j;
    for (i = 0; i < l; i++) {
        contains_string = 1;
        for(j = 0; j < sts_length; j++) {
            if (string[i + j] != string_to_search[j]) {
                contains_string = 0;
                break;
            }
        }
        if (contains_string) {
            break;
        }
    }
    return i;
}

bool_t strops_contains_char(const char* string, char char_to_search) {
    ull_t i;
    for (i = 0; i < strops_length(string) + 1; i++) {
        if (string[i] == char_to_search) {
            return 1;
        }
    }
    return 0;
}

bool_t strops_contains_string(const char* string, const char* string_to_search) {
    bool_t contains_string = 0;
    ull_t sts_length = strops_length(string_to_search);
    ull_t l = strops_length(string) - sts_length + 1;
    ull_t i, j;
    for (i = 0; i < l; i++) {
        contains_string = 1;
        for(j = 0; j < sts_length; j++) {
            if (string[i + j] != string_to_search[j]) {
                contains_string = 0;
                break;
            }
        }
        if (contains_string) {
            break;
        }
    }
    return contains_string;
}

bool_t strops_equals(const char* string1, const char* string2) {
    if (strops_length(string1) != strops_length(string2)) {
        return 0;
    }
    bool_t equal = 1;
    ull_t i;
    for (i = 0; i < strops_length(string1); i++) {
        if (string1[i] != string2[i]) {
            equal = 0;
            break;
        }
    }
    return equal;
}

bool_t strops_starts_with(const char* string1, const char* string2) {
    if (strops_length(string1) < strops_length(string2)) {
        return 0;   
    }
    bool_t starts_with = 1;
    ull_t i;
    for (i = 0; i < strops_length(string2); i++) {
        if (string1[i] != string2[i]) {
            starts_with = 0;
            break;
        }
    }
    return starts_with;
}

char* strops_to_lowercase(const char* string) {
    char* result = strops_copy(string);
    ull_t i;
    for (i = 0; i < strops_length(string); i++) {
        if (result[i] >= 'A' && result[i] <= 'Z') {
            result[i] += 32;
        }
    }
    return result;
}

char* strops_to_uppercase(const char* string) {
    char* result = strops_copy(string);
    ull_t i;
    for (i = 0; i < strops_length(string); i++) {
        if (result[i] >= 'a' && result[i] <= 'z') {
            result[i] -= 32;
        }
    }
    return result;
}

bool_t strops_is_lowercase(const char* string) {
    ull_t i;
    for (i = 0; i < strops_length(string); i++) {
        if (!(string[i] >= 'a' && string[i] <= 'z')) {
            return 0;
        }
    }
    return 1;
}

bool_t strops_is_uppercase(const char* string) {
    ull_t i;
    for (i = 0; i < strops_length(string); i++) {
        if (!(string[i] >= 'A' && string[i] <= 'Z')) {
            return 0;
        }
    }
    return 1;
}

char* strops_insert_at_pos_string(const char* string, const char* string_to_insert, ull_t pos) {
    assert(pos <= strops_length(string) && "pos needs to be inside string");
    ull_t string_length = strops_length(string) + strops_length(string_to_insert) + 1;
    char* result = strops_copy(string);
    ull_t i, j;
    /* Make space for string_to_insert */
    for (i = string_length - 1; i > pos; i--) {
        result[i] = result[i - strops_length(string_to_insert)];
    }
    /* Insert string into empty space */
    for (j = 0; j < strops_length(string_to_insert); j++) {
        result[pos + j] = string_to_insert[j];
    }
    return result;
}

char* strops_remove_at_pos_char(const char* string, ull_t pos) {
    assert(pos <= strops_length(string) && "pos needs to be inside string");
    char* result = strops_copy(string);
    result[pos] = 0;
    ull_t i;
    for (i = pos; i < strops_length(string); i++) {
        result[i] = result[i + 1];
    }
    return result;
}

void strops_remove_at_pos_char_inplace(char* string, ull_t pos) {
    assert(pos <= strops_length(string) && "pos needs to be inside string");
    ull_t length = strops_length(string);
    string[pos] = 0;
    ull_t i;
    for (i = pos; i < length; i++) {
        string[i] = string[i + 1];
    }
}

char* strops_trim_right_whitespace(const char* string) {
    char* result = strops_copy(string);
    char* tmp;
    while (strops_contains_char("\t\n\v\f\r ", result[strops_length(result) - 1])) {
        strops_remove_at_pos_char_inplace(result, strops_length(result) - 1);
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_trim_left_whitespace(const char* string) {
    char* result = strops_copy(string);
    while (strops_contains_char("\t\n\v\f\r ", result[0])) {
        strops_remove_at_pos_char_inplace(result, 0);
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_trim_both_whitespace(const char* string) {
    char* result;
    char* tmp;
    tmp = strops_trim_right_whitespace(string);
    result = strops_trim_left_whitespace(tmp);
    free(tmp);
    return result;
}

char* strops_trim_right_chars(const char* string, const char* chars_to_remove) {
    char* result = strops_copy(string);
    while (strops_contains_char(chars_to_remove, result[strops_length(result) - 1])) {
        strops_remove_at_pos_char_inplace(result, strops_length(result) - 1);
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_trim_left_chars(const char* string, const char* chars_to_remove) {
    char* result = strops_copy(string);
    while (strops_contains_char(chars_to_remove, result[0])) {
        strops_remove_at_pos_char_inplace(result, 0);
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_trim_both_chars(const char* string, const char* chars_to_remove) {
    char* result;
    char* tmp;
    tmp = strops_trim_right_chars(string, chars_to_remove);
    result = strops_trim_left_chars(tmp, chars_to_remove);
    free(tmp);
    return result;
}

char* strops_trim_right_string(const char* string, const char* string_to_remove) {
    assert(strops_length(string) >= strops_length(string_to_remove) && "string_to_remove cannot be bigger than string");
    char* result = strops_copy(string);
    ull_t offset = strops_length(result) - strops_length(string_to_remove);
    char* tmp = result + offset;

    while (strops_equals(tmp, string_to_remove)) {
        ull_t i;
        for (i = 0; i < strops_length(string_to_remove); i++) {
            strops_remove_at_pos_char_inplace(result, offset);
        }
        offset = strops_length(result) - strops_length(string_to_remove);
        tmp = result + offset;
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_trim_left_string(const char* string, const char* string_to_remove) {
    assert(strops_length(string) >= strops_length(string_to_remove) && "string_to_remove cannot be bigger than string");
    char* result = strops_copy(string);

    while (strops_first_pos_of_string(result, string_to_remove) == 0) {
        ull_t i;
        for (i = 0; i < strops_length(string_to_remove); i++) {
            strops_remove_at_pos_char_inplace(result, 0);
        }
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_trim_both_string(const char* string, const char* string_to_remove) {
    assert(strops_length(string) >= strops_length(string_to_remove) && "string_to_remove cannot be bigger than string");
    char* result;
    char* tmp;
    tmp = strops_trim_right_string(string, string_to_remove);
    result = strops_trim_left_string(tmp, string_to_remove);
    return result;
}

char* strops_remove_chars(const char* string, const char* chars_to_remove) {
    char* result = strops_copy(string);

    ull_t i, j;
    for (i = 0; i < strops_length(chars_to_remove); i++) {
        while (strops_contains_char(result, chars_to_remove[i])) {
            strops_remove_at_pos_char_inplace(result, strops_first_pos_of_char(result, chars_to_remove[i]));
        }
    }
    result = realloc(result, strops_length(result));
    return result;
}

char* strops_remove_string(const char* string, const char* string_to_remove) {
    assert(strops_length(string) >= strops_length(string_to_remove) && "string_to_remove cannot be bigger than string");
    char* result = strops_copy(string);

    while (strops_contains_string(result, string_to_remove)) {
        ull_t offset = strops_first_pos_of_string(result, string_to_remove);
        ull_t i;
        for (i = 0; i < strops_length(string_to_remove); i++) {
            strops_remove_at_pos_char_inplace(result, offset);
        }
    }
    result = realloc(result, strops_length(result));
    return result;
}

ull_t strops_word_count(const char* string) {
    ull_t word_count = 0;
    char* tmp = strops_copy(string);

    ull_t i = 0;
    ull_t beginning_of_word = 0;
    while (i < strops_length(string) - 1) {
        for (; i < strops_length(tmp); i++) {
            if ((tmp[i] >= 'A' && tmp[i] <= 'Z') || (tmp[i] >= 'a' && tmp[i] <= 'z')) {
                beginning_of_word = i;
                break;
            }
        }

        if (!strops_contains_char("\t\n\v\f\r ", tmp[beginning_of_word - 1])) {
            continue;
        }

        for (i = beginning_of_word; i < strops_length(tmp); i++) {
            if (!(tmp[i] >= 'A' && tmp[i] <= 'Z') && !(tmp[i] >= 'a' && tmp[i] <= 'z')) {
                break;
            }
        }

        if (!strops_contains_char("\t\n\v\f\r ", tmp[i + 1])) {
            continue;
        }

        if (i - beginning_of_word < 2) {
            continue;
        }
        
        word_count++;
    }
    free(tmp);
    return word_count;
}