#include <assert.h>
#include <ctype.h>
#include <err.h>
#include <gc.h>
#include <gc/cord.h>
#include <limits.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdlib.h>
#include <sys/param.h>
#include <unistr.h>
#include <unicase.h>

#include "../SipHash/halfsiphash.h"
#include "types.h"
#include "array.h"
#include "string.h"

#define CLAMP(x, lo, hi) MIN(hi, MAX(x,lo))

public CORD Str__as_str(const void *str, bool colorize, const TypeInfo *info)
{
    (void)info;
    if (!str) return "Str";
    return Str__quoted(*(CORD*)str, colorize);
}

public CORD Str__quoted(CORD str, bool colorize)
{
    // Note: it's important to have unicode strings not get broken up with
    // escapes, otherwise they won't print right.
    if (colorize) {
        CORD quoted = "\x1b[35m\"";
        CORD_pos i;
        CORD_FOR(i, str) {
            char c = CORD_pos_fetch(i);
            switch (c) {
#define BACKSLASHED(esc) "\x1b[34m\\\x1b[1m" esc "\x1b[0;35m"
            case '\a': quoted = CORD_cat(quoted, BACKSLASHED("a")); break;
            case '\b': quoted = CORD_cat(quoted, BACKSLASHED("b")); break;
            case '\x1b': quoted = CORD_cat(quoted, BACKSLASHED("e")); break;
            case '\f': quoted = CORD_cat(quoted, BACKSLASHED("f")); break;
            case '\n': quoted = CORD_cat(quoted, BACKSLASHED("n")); break;
            case '\r': quoted = CORD_cat(quoted, BACKSLASHED("r")); break;
            case '\t': quoted = CORD_cat(quoted, BACKSLASHED("t")); break;
            case '\v': quoted = CORD_cat(quoted, BACKSLASHED("v")); break;
            case '"': quoted = CORD_cat(quoted, BACKSLASHED("\"")); break;
            case '\\': quoted = CORD_cat(quoted, BACKSLASHED("\\")); break;
            case '\x00' ... '\x06': case '\x0E' ... '\x1A':
            case '\x1C' ... '\x1F': case '\x7F' ... '\x7F':
                CORD_sprintf(&quoted, "%r" BACKSLASHED("x%02X"), quoted, c);
                break;
            default: quoted = CORD_cat_char(quoted, c); break;
#undef BACKSLASHED
            }
        }
        quoted = CORD_cat(quoted, "\"\x1b[m");
        return quoted;
    } else {
        CORD quoted = "\"";
        CORD_pos i;
        CORD_FOR(i, str) {
            char c = CORD_pos_fetch(i);
            switch (c) {
            case '\a': quoted = CORD_cat(quoted, "\\a"); break;
            case '\b': quoted = CORD_cat(quoted, "\\b"); break;
            case '\x1b': quoted = CORD_cat(quoted, "\\e"); break;
            case '\f': quoted = CORD_cat(quoted, "\\f"); break;
            case '\n': quoted = CORD_cat(quoted, "\\n"); break;
            case '\r': quoted = CORD_cat(quoted, "\\r"); break;
            case '\t': quoted = CORD_cat(quoted, "\\t"); break;
            case '\v': quoted = CORD_cat(quoted, "\\v"); break;
            case '"': quoted = CORD_cat(quoted, "\\\""); break;
            case '\\': quoted = CORD_cat(quoted, "\\\\"); break;
            case '\x00' ... '\x06': case '\x0E' ... '\x1A':
            case '\x1C' ... '\x1F': case '\x7F' ... '\x7F':
                CORD_sprintf(&quoted, "%r\\x%02X", quoted, c);
                break;
            default: quoted = CORD_cat_char(quoted, c); break;
            }
        }
        quoted = CORD_cat_char(quoted, '"');
        return quoted;
    }
}

public int Str__compare(CORD *x, CORD *y)
{
    return CORD_cmp(*x, *y);
}

public bool Str__equal(CORD *x, CORD *y)
{
    return CORD_cmp(*x, *y) == 0;
}

public uint32_t Str__hash(CORD *cord)
{
    if (!*cord) return 0;

    const char *str = CORD_to_const_char_star(*cord);
    *cord = str;

    uint32_t hash;
    halfsiphash(str, strlen(str)+1, SSS_HASH_VECTOR, (uint8_t*)&hash, sizeof(hash));
    return hash;
}

public CORD Str__uppercased(CORD str)
{
    if (!str) return str;
    size_t len = strlen(str) + 1;
    uint8_t *dest = GC_MALLOC_ATOMIC(len);
    return (CORD)u8_toupper((const uint8_t*)str, len-1, uc_locale_language(), NULL, dest, &len);
}

public CORD Str__lowercased(CORD str)
{
    if (!str) return str;
    size_t len = strlen(str) + 1;
    uint8_t *dest = GC_MALLOC_ATOMIC(len);
    return (CORD)u8_tolower((const uint8_t*)str, len-1, uc_locale_language(), NULL, dest, &len);
}

public CORD Str__titlecased(CORD str)
{
    if (!str) return str;
    size_t len = strlen(str) + 1;
    uint8_t *dest = GC_MALLOC_ATOMIC(len);
    return (CORD)u8_totitle((const uint8_t*)str, len-1, uc_locale_language(), NULL, dest, &len);
}

public bool Str__has(CORD str, CORD target, where_e where)
{
    if (!target) return true;
    if (!str) return false;

    if (where == WHERE_START) {
        return (CORD_ncmp(str, 0, target, 0, CORD_len(target)) == 0);
    } else if (where == WHERE_END) {
        size_t str_len = CORD_len(str);
        size_t target_len = CORD_len(target);
        return (str_len >= target_len && CORD_ncmp(str, str_len-target_len, target, 0, target_len) == 0);
    } else {
        size_t pos = CORD_str(str, 0, target);
        return (pos != CORD_NOT_FOUND);
    }
}

public CORD Str__without(CORD str, CORD target, where_e where)
{
    if (!str || !target) return str;

    size_t target_len = CORD_len(target);
    if (where == WHERE_START) {
        if (CORD_ncmp(str, 0, target, 0, target_len) == 0)
            return CORD_substr(str, target_len, SIZE_MAX);
        return str;
    } else if (where == WHERE_END) {
        size_t str_len = CORD_len(str);
        if (CORD_ncmp(str, str_len-target_len, target, 0, target_len) == 0)
            return CORD_substr(str, 0, str_len - target_len);
        return str;
    } else {
        errx(1, "Not implemented");
    }
}

public CORD Str__trimmed(CORD str, CORD skip, where_e where)
{
    if (!str || !skip) return str;
    const uint8_t *ustr = (const uint8_t*)CORD_to_const_char_star(str);
    const uint8_t *uskip = (const uint8_t*)CORD_to_const_char_star(skip);
    if (where == WHERE_START) {
        size_t span = u8_strspn(ustr, uskip);
        return (CORD)ustr + span;
    } else if (where == WHERE_END) {
        size_t len = u8_strlen(ustr);
        const uint8_t *back = ustr + len;
        size_t back_span = 0;
        while (back - back_span > ustr && u8_strspn(back-back_span-1, uskip) > back_span)
            ++back_span;
        return CORD_substr((CORD)ustr, 0, len - back_span);
    } else {
        size_t span = u8_strspn(ustr, uskip);
        size_t len = u8_strlen(ustr);
        const uint8_t *back = ustr + len;
        size_t back_span = 0;
        while (back - back_span > ustr + span && u8_strspn(back-back_span-1, uskip) > back_span)
            ++back_span;
        return CORD_substr((CORD)(ustr + span), 0, len - span - back_span);
    }
}

public CORD Str__slice(CORD str, int64_t first, int64_t stride, int64_t length)
{
    if (stride != 1) errx(1, "Slicing with non-1 stride is not supported");
    return CORD_substr(str, first-1, length);
}

public find_result_t Str__find(CORD str, CORD pat)
{
    if (!pat) return (find_result_t){.status=FIND_SUCCESS, .index=1};
    size_t pos = CORD_str(str, 0, pat);
    return (pos == CORD_NOT_FOUND) ? (find_result_t){.status=FIND_FAILURE} : (find_result_t){.status=FIND_SUCCESS, .index=(int32_t)pos};
}

public CORD Str__replace(CORD text, CORD pat, CORD replacement, int64_t limit)
{
    if (!text || !pat) return text;
    CORD ret = NULL;
    size_t pos = 0, pat_len = CORD_len(pat);
    for (size_t found; limit > 0 && (found=CORD_str(text, pos, pat)) != CORD_NOT_FOUND; --limit) {
        ret = CORD_cat(ret, CORD_substr(text, pos, found));
        ret = CORD_cat(ret, replacement);
        pos = found + pat_len;
    }
    return CORD_cat(ret, CORD_substr(text, pos, SIZE_MAX));
}

public Str_Array_t Str__split(CORD str, CORD split)
{
    if (!str) return (Str_Array_t){.stride=sizeof(CORD)};
    Str_Array_t strings = {.stride=sizeof(CORD)};
    int64_t capacity = 0;

    const uint8_t *ustr = (uint8_t*)CORD_to_const_char_star(str);
    const uint8_t *usplit = (uint8_t*)CORD_to_const_char_star(split);
    for (int64_t i = 0; ; ) {
        i += u8_strcspn(ustr + i, usplit);
        size_t span = u8_strspn(ustr + i, usplit);
        if (span > 0) {
            CORD chunk = CORD_substr((CORD)ustr, i, i+span);
            if (capacity <= 0)
                strings.data = GC_REALLOC(strings.data, sizeof(CORD)*(capacity += 10));
            strings.data[strings.length++] = chunk;
            i += span;
        } else {
            break;
        }
    }
    return strings;
}

public CORD Str__join(CORD glue, Str_Array_t pieces)
{
    if (pieces.length == 0) return CORD_EMPTY;

    CORD ret = CORD_EMPTY;
    for (int64_t i = 0; i < pieces.length; i++) {
        if (i > 0) ret = CORD_cat(ret, glue);
        ret = CORD_cat(ret, *(CORD*)((void*)pieces.data + i*pieces.stride));
    }
    return ret;
}

public Str_namespace_t Str = {
    .type={
        .size=sizeof(CORD),
        .align=__alignof__(CORD),
        .tag=CustomInfo,
        .CustomInfo={
            .as_str=(void*)Str__as_str,
            .compare=(void*)Str__compare,
            .equal=(void*)Str__equal,
            .hash=(void*)Str__hash,
        },
    },
    .uppercased=Str__uppercased,
    .lowercased=Str__lowercased,
    .titlecased=Str__titlecased,
    .has=Str__has,
    .without=Str__without,
    .trimmed=Str__trimmed,
    .slice=Str__slice,
    .find=Str__find,
    .replace=Str__replace,
    .quoted=Str__quoted,
    .split=Str__split,
    .join=Str__join,
};

// vim: ts=4 sw=0 et cino=L2,l1,(0,W4,m1,\:0