/** \file xdgmimeglob.cpp
*/
/* -*- mode: C; c-file-style: "gnu" -*- */
/* xdgmimeglob.cpp: Private file.  Datastructure for storing the globs.
 *
 * More info can be found at http://www.freedesktop.org/standards/
 *
 * Copyright (C) 2003  Red Hat, Inc.
 * Copyright (C) 2003  Jonathan Blandford <jrb@alum.mit.edu>
 *
 * Licensed under the Academic Free License version 2.0
 * Or under the following terms:
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.   See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the
 * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA  02110-1301, USA.
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "xdgmimeglob.h"
#include "xdgmimeint.h"
#include <stdlib.h>
#include <stdio.h>
#include <assert.h>
#include <string.h>
#include <fnmatch.h>

#ifndef  FALSE
#define  FALSE  (0)
#endif

#ifndef  TRUE
#define  TRUE  (!FALSE)
#endif

typedef struct XdgGlobHashNode XdgGlobHashNode;
typedef struct XdgGlobList XdgGlobList;

struct XdgGlobHashNode
{
    xdg_unichar_t character;
    const char *mime_type;
    XdgGlobHashNode *next;
    XdgGlobHashNode *child;
};
struct XdgGlobList
{
    const char *data;
    const char *mime_type;
    XdgGlobList *next;
};

struct XdgGlobHash
{
    XdgGlobList *literal_list;
    XdgGlobHashNode *simple_node;
    XdgGlobList *full_list;
};


/* XdgGlobList
 */
static XdgGlobList *
_xdg_glob_list_new(void)
{
    XdgGlobList *new_element;

    new_element = (XdgGlobList *)calloc(1, sizeof(XdgGlobList));

    return new_element;
}

/* Frees glob_list and all of it's children */
static void
_xdg_glob_list_free(XdgGlobList *glob_list)
{
    XdgGlobList *ptr, *next;

    ptr = glob_list;

    while (ptr != NULL)
    {
        next = ptr->next;

        if (ptr->data)
            free((void *) ptr->data);
        if (ptr->mime_type)
            free((void *) ptr->mime_type);
        free(ptr);

        ptr = next;
    }
}

static XdgGlobList *
_xdg_glob_list_append(XdgGlobList *glob_list,
                      void        *data,
                      const char  *mime_type)
{
    XdgGlobList *new_element;
    XdgGlobList *tmp_element;

    new_element = _xdg_glob_list_new();
    new_element->data = (const char *)data;
    new_element->mime_type = mime_type;
    if (glob_list == NULL)
        return new_element;

    tmp_element = glob_list;
    while (tmp_element->next != NULL)
        tmp_element = tmp_element->next;

    tmp_element->next = new_element;

    return glob_list;
}

#if 0
static XdgGlobList *
_xdg_glob_list_prepend(XdgGlobList *glob_list,
                       void        *data,
                       const char  *mime_type)
{
    XdgGlobList *new_element;

    new_element = _xdg_glob_list_new();
    new_element->data = data;
    new_element->next = glob_list;
    new_element->mime_type = mime_type;

    return new_element;
}
#endif

/* XdgGlobHashNode
 */

static XdgGlobHashNode *
_xdg_glob_hash_node_new(void)
{
    XdgGlobHashNode *glob_hash_node;

    glob_hash_node = (XdgGlobHashNode *)calloc(1, sizeof(XdgGlobHashNode));

    return glob_hash_node;
}

static void
_xdg_glob_hash_node_dump(XdgGlobHashNode *glob_hash_node,
                         int depth)
{
    int i;
    for (i = 0; i < depth; i++)
        printf(" ");

    printf("%c", (char)glob_hash_node->character);
    if (glob_hash_node->mime_type)
        printf(" - %s\n", glob_hash_node->mime_type);
    else
        printf("\n");
    if (glob_hash_node->child)
        _xdg_glob_hash_node_dump(glob_hash_node->child, depth + 1);
    if (glob_hash_node->next)
        _xdg_glob_hash_node_dump(glob_hash_node->next, depth);
}

static XdgGlobHashNode *
_xdg_glob_hash_insert_text(XdgGlobHashNode *glob_hash_node,
                           const char      *text,
                           const char      *mime_type)
{
    XdgGlobHashNode *node;
    xdg_unichar_t character;

    character = _xdg_utf8_to_ucs4(text);

    if ((glob_hash_node == NULL) ||
            (character < glob_hash_node->character))
    {
        node = _xdg_glob_hash_node_new();
        node->character = character;
        node->next = glob_hash_node;
        glob_hash_node = node;
    }
    else if (character == glob_hash_node->character)
    {
        node = glob_hash_node;
    }
    else
    {
        XdgGlobHashNode *prev_node;
        int found_node = FALSE;

        /* Look for the first character of text in glob_hash_node, and insert it if we
         * have to.*/
        prev_node = glob_hash_node;
        node = prev_node->next;

        while (node != NULL)
        {
            if (character < node->character)
            {
                node = _xdg_glob_hash_node_new();
                node->character = character;
                node->next = prev_node->next;
                prev_node->next = node;

                found_node = TRUE;
                break;
            }
            else if (character == node->character)
            {
                found_node = TRUE;
                break;
            }
            prev_node = node;
            node = node->next;
        }

        if (! found_node)
        {
            node = _xdg_glob_hash_node_new();
            node->character = character;
            node->next = prev_node->next;
            prev_node->next = node;
        }
    }

    text = _xdg_utf8_next_char(text);
    if (*text == '\000')
    {
        node->mime_type = mime_type;
    }
    else
    {
        node->child = _xdg_glob_hash_insert_text(node->child, text, mime_type);
    }
    return glob_hash_node;
}

static const char *
_xdg_glob_hash_node_lookup_file_name(XdgGlobHashNode *glob_hash_node,
                                     const char      *file_name,
                                     int              ignore_case)
{
    XdgGlobHashNode *node;
    xdg_unichar_t character;

    if (glob_hash_node == NULL)
        return NULL;

    character = _xdg_utf8_to_ucs4(file_name);
    if (ignore_case)
        character = _xdg_ucs4_to_lower(character);

    for (node = glob_hash_node; node && character >= node->character; node = node->next)
    {
        if (character == node->character)
        {
            file_name = _xdg_utf8_next_char(file_name);
            if (*file_name == '\000')
                return node->mime_type;
            else
                return _xdg_glob_hash_node_lookup_file_name(node->child,
                        file_name,
                        ignore_case);
        }
    }
    return NULL;
}

const char *
_xdg_glob_hash_lookup_file_name(XdgGlobHash *glob_hash,
                                const char  *file_name)
{
    XdgGlobList *list;
    const char *mime_type;
    const char *ptr;
    /* First, check the literals */

    assert(file_name != NULL);

    for (list = glob_hash->literal_list; list; list = list->next)
        if (strcmp((const char *)list->data, file_name) == 0)
            return list->mime_type;

    ptr = strchr(file_name, '.');
    while (ptr != NULL)
    {
        mime_type = (_xdg_glob_hash_node_lookup_file_name(glob_hash->simple_node, ptr, FALSE));
        if (mime_type != NULL)
            return mime_type;

        mime_type = (_xdg_glob_hash_node_lookup_file_name(glob_hash->simple_node, ptr, TRUE));
        if (mime_type != NULL)
            return mime_type;

        ptr = strchr(ptr+1, '.');
    }

    /* FIXME: Not UTF-8 safe */
    for (list = glob_hash->full_list; list; list = list->next)
        if (fnmatch((const char *)list->data, file_name, 0) == 0)
            return list->mime_type;

    return NULL;
}



/* XdgGlobHash
 */

XdgGlobHash *
_xdg_glob_hash_new(void)
{
    XdgGlobHash *glob_hash;

    glob_hash = (XdgGlobHash *)calloc(1, sizeof(XdgGlobHash));

    return glob_hash;
}


static void
_xdg_glob_hash_free_nodes(XdgGlobHashNode *node)
{
    if (node)
    {
        if (node->child)
            _xdg_glob_hash_free_nodes(node->child);
        if (node->next)
            _xdg_glob_hash_free_nodes(node->next);
        if (node->mime_type)
            free((void *) node->mime_type);
        free(node);
    }
}

void
_xdg_glob_hash_free(XdgGlobHash *glob_hash)
{
    _xdg_glob_list_free(glob_hash->literal_list);
    _xdg_glob_list_free(glob_hash->full_list);
    _xdg_glob_hash_free_nodes(glob_hash->simple_node);
    free(glob_hash);
}

XdgGlobType
_xdg_glob_determine_type(const char *glob)
{
    const char *ptr;
    int maybe_in_simple_glob = FALSE;
    int first_char = TRUE;

    ptr = glob;

    while (*ptr != '\000')
    {
        if (*ptr == '*' && first_char)
            maybe_in_simple_glob = TRUE;
        else if (*ptr == '\\' || *ptr == '[' || *ptr == '?' || *ptr == '*')
            return XDG_GLOB_FULL;

        first_char = FALSE;
        ptr = _xdg_utf8_next_char(ptr);
    }
    if (maybe_in_simple_glob)
        return XDG_GLOB_SIMPLE;
    else
        return XDG_GLOB_LITERAL;
}

/* glob must be valid UTF-8 */
void
_xdg_glob_hash_append_glob(XdgGlobHash *glob_hash,
                           const char  *glob,
                           const char  *mime_type)
{
    XdgGlobType type;

    assert(glob_hash != NULL);
    assert(glob != NULL);

    type = _xdg_glob_determine_type(glob);

    switch (type)
    {
        case XDG_GLOB_LITERAL:
            glob_hash->literal_list = _xdg_glob_list_append(glob_hash->literal_list, strdup(glob), strdup(mime_type));
            break;
        case XDG_GLOB_SIMPLE:
            glob_hash->simple_node = _xdg_glob_hash_insert_text(glob_hash->simple_node, glob + 1, strdup(mime_type));
            break;
        case XDG_GLOB_FULL:
            glob_hash->full_list = _xdg_glob_list_append(glob_hash->full_list, strdup(glob), strdup(mime_type));
            break;
    }
}

void
_xdg_glob_hash_dump(XdgGlobHash *glob_hash)
{
    XdgGlobList *list;
    printf("LITERAL STRINGS\n");
    if (glob_hash->literal_list == NULL)
    {
        printf("    None\n");
    }
    else
    {
        for (list = glob_hash->literal_list; list; list = list->next)
            printf("    %s - %s\n", (char *)list->data, list->mime_type);
    }
    printf("\nSIMPLE GLOBS\n");
    _xdg_glob_hash_node_dump(glob_hash->simple_node, 4);

    printf("\nFULL GLOBS\n");
    if (glob_hash->full_list == NULL)
    {
        printf("    None\n");
    }
    else
    {
        for (list = glob_hash->full_list; list; list = list->next)
            printf("    %s - %s\n", (char *)list->data, list->mime_type);
    }
}


void
_xdg_mime_glob_read_from_file(XdgGlobHash *glob_hash,
                              const char  *file_name)
{
    FILE *glob_file;
    char line[255];

    /* OK to not use CLO_EXEC here because mimedb is single threaded */
    glob_file = fopen(file_name, "r");

    if (glob_file == NULL)
        return;

    /* FIXME: Not UTF-8 safe.  Doesn't work if lines are greater than 255 chars.
     * Blah */
    while (fgets(line, 255, glob_file) != NULL)
    {
        char *colon;
        if (line[0] == '#')
            continue;

        colon = strchr(line, ':');
        if (colon == NULL)
            continue;
        *(colon++) = '\000';
        colon[strlen(colon) -1] = '\000';
        _xdg_glob_hash_append_glob(glob_hash, colon, line);
    }

    fclose(glob_file);
}