/*
 * Copyright (C) 2007 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#define LOG_TAG "sqlite3_android"

#include <ctype.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifdef SQLITE_ENABLE_ICU
#include <unicode/ucol.h>
#include <unicode/uiter.h>
#include <unicode/ustring.h>
#include <unicode/utypes.h>
#endif //SQLITE_ENABLE_ICU
#include <log/log.h>

#include "sqlite3_android.h"
#include "PhoneNumberUtils.h"

#define ENABLE_ANDROID_LOG 0
#define SMALL_BUFFER_SIZE 10
#define PHONE_NUMBER_BUFFER_SIZE 40

#ifdef SQLITE_ENABLE_ICU
static int collate16(void *p, int n1, const void *v1, int n2, const void *v2)
{
    UCollator *coll = (UCollator *) p;
    UCollationResult result = ucol_strcoll(coll, (const UChar *) v1, n1,
                                                 (const UChar *) v2, n2);

    if (result == UCOL_LESS) {
        return -1;
    } else if (result == UCOL_GREATER) {
        return 1;
    } else {
        return 0;
    }
}

static int collate8(void *p, int n1, const void *v1, int n2, const void *v2)
{
    UCollator *coll = (UCollator *) p;
    UCharIterator i1, i2;
    UErrorCode status = U_ZERO_ERROR;

    uiter_setUTF8(&i1, (const char *) v1, n1);
    uiter_setUTF8(&i2, (const char *) v2, n2);

    UCollationResult result = ucol_strcollIter(coll, &i1, &i2, &status);

    if (U_FAILURE(status)) {
//        ALOGE("Collation iterator error: %d\n", status);
    }

    if (result == UCOL_LESS) {
        return -1;
    } else if (result == UCOL_GREATER) {
        return 1;
    } else {
        return 0;
    }
}
#endif // SQLITE_ENABLE_ICU

static void phone_numbers_equal(sqlite3_context * context, int argc, sqlite3_value ** argv)
{
    if (argc != 2 && argc != 3) {
        sqlite3_result_int(context, 0);
        return;
    }

    char const * num1 = (char const *)sqlite3_value_text(argv[0]);
    char const * num2 = (char const *)sqlite3_value_text(argv[1]);

    bool use_strict = false;
    if (argc == 3) {
        use_strict = (sqlite3_value_int(argv[2]) != 0);
    }

    if (num1 == NULL || num2 == NULL) {
        sqlite3_result_null(context);
        return;
    }

    bool equal =
        (use_strict ?
         android::phone_number_compare_strict(num1, num2) :
         android::phone_number_compare_loose(num1, num2));

    if (equal) {
        sqlite3_result_int(context, 1);
    } else {
        sqlite3_result_int(context, 0);
    }
}

static void phone_number_stripped_reversed(sqlite3_context * context, int argc,
      sqlite3_value ** argv)
{
    if (argc != 1) {
        sqlite3_result_int(context, 0);
        return;
    }

    char const * number = (char const *)sqlite3_value_text(argv[0]);
    if (number == NULL) {
        sqlite3_result_null(context);
        return;
    }

    char out[PHONE_NUMBER_BUFFER_SIZE];
    int outlen = 0;
    android::phone_number_stripped_reversed_inter(number, out, PHONE_NUMBER_BUFFER_SIZE, &outlen);
    sqlite3_result_text(context, (const char*)out, outlen, SQLITE_TRANSIENT);
}


#if ENABLE_ANDROID_LOG
static void android_log(sqlite3_context * context, int argc, sqlite3_value ** argv)
{
    char const * tag = "sqlite_trigger";
    char const * msg = "";
    int msgIndex = 0;

    switch (argc) {
        case 2:
            tag = (char const *)sqlite3_value_text(argv[0]);
            if (tag == NULL) {
                tag = "sqlite_trigger";
            }
            msgIndex = 1;
        case 1:
            msg = (char const *)sqlite3_value_text(argv[msgIndex]);
            if (msg == NULL) {
                msg = "";
            }
            ALOG(LOG_INFO, tag, "%s", msg);
            sqlite3_result_int(context, 1);
            return;

        default:
            sqlite3_result_int(context, 0);
            return;
    }
}
#endif

static void delete_file(sqlite3_context * context, int argc, sqlite3_value ** argv)
{
    if (argc != 1) {
        sqlite3_result_int(context, 0);
        return;
    }

    char const * path = (char const *)sqlite3_value_text(argv[0]);
    // Don't allow ".." in paths
    if (path == NULL || strstr(path, "/../") != NULL) {
        sqlite3_result_null(context);
        return;
    }

    // We only allow deleting files in the EXTERNAL_STORAGE path, or one of the
    // SECONDARY_STORAGE paths
    bool good_path = false;
    char const * external_storage = getenv("EXTERNAL_STORAGE");
    if (external_storage && strncmp(external_storage, path, strlen(external_storage)) == 0) {
        good_path = true;
    } else {
        // check SECONDARY_STORAGE, which should be a colon separated list of paths
        char const * secondary_paths = getenv("SECONDARY_STORAGE");
        while (secondary_paths && secondary_paths[0]) {
            const char* colon = strchr(secondary_paths, ':');
            int length = (colon ? colon - secondary_paths : strlen(secondary_paths));
            if (strncmp(secondary_paths, path, length) == 0) {
                good_path = true;
            }
            secondary_paths += length;
            while (*secondary_paths == ':') secondary_paths++;
        }
    }

    if (!good_path) {
        sqlite3_result_null(context);
        return;
    }

    int err = unlink(path);
    if (err != -1) {
        // No error occured, return true
        sqlite3_result_int(context, 1);
    } else {
        // An error occured, return false
        sqlite3_result_int(context, 0);
    }
}

#ifdef SQLITE_ENABLE_ICU
static void tokenize_auxdata_delete(void * data)
{
    sqlite3_stmt * statement = (sqlite3_stmt *)data;
    sqlite3_finalize(statement);
}

static void base16Encode(char* dest, const char* src, uint32_t size)
{
    static const char * BASE16_TABLE = "0123456789abcdef";
    for (uint32_t i = 0; i < size; i++) {
        char ch = *src++;
        *dest++ = BASE16_TABLE[ (ch & 0xf0) >> 4 ];
        *dest++ = BASE16_TABLE[ (ch & 0x0f)      ];
    }
}

struct SqliteUserData {
    sqlite3 * handle;
    UCollator* collator;
};

static void localized_collator_dtor(UCollator* collator)
{
    ucol_close(collator);
}

#define LOCALIZED_COLLATOR_NAME "LOCALIZED"

// This collator may be removed in the near future, so you MUST not use now.
#define PHONEBOOK_COLLATOR_NAME "PHONEBOOK"

#endif // SQLITE_ENABLE_ICU

extern "C" int register_localized_collators(sqlite3* handle __attribute((unused)),
                                            const char* systemLocale __attribute((unused)),
                                            int utf16Storage __attribute((unused)))
{
// This function is no-op for the VNDK, but should exist in case when some vendor
// module has a reference to this function.
#ifdef SQLITE_ENABLE_ICU
    UErrorCode status = U_ZERO_ERROR;
    UCollator* collator = ucol_open(systemLocale, &status);
    if (U_FAILURE(status)) {
        return -1;
    }

    ucol_setAttribute(collator, UCOL_STRENGTH, UCOL_PRIMARY, &status);
    if (U_FAILURE(status)) {
        return -1;
    }

    int err;
    if (utf16Storage) {
        err = sqlite3_create_collation_v2(handle, LOCALIZED_COLLATOR_NAME, SQLITE_UTF16, collator,
                collate16, (void(*)(void*))localized_collator_dtor);
    } else {
        err = sqlite3_create_collation_v2(handle, LOCALIZED_COLLATOR_NAME, SQLITE_UTF8, collator,
                collate8, (void(*)(void*))localized_collator_dtor);
    }

    if (err != SQLITE_OK) {
        return err;
    }

    //// PHONEBOOK_COLLATOR
    status = U_ZERO_ERROR;
    collator = ucol_open(systemLocale, &status);
    if (U_FAILURE(status)) {
        return -1;
    }

    status = U_ZERO_ERROR;
    ucol_setAttribute(collator, UCOL_STRENGTH, UCOL_PRIMARY, &status);
    if (U_FAILURE(status)) {
        return -1;
    }

    if (utf16Storage) {
        err = sqlite3_create_collation_v2(handle, PHONEBOOK_COLLATOR_NAME, SQLITE_UTF16, collator,
                collate16, (void(*)(void*))localized_collator_dtor);
    } else {
        err = sqlite3_create_collation_v2(handle, PHONEBOOK_COLLATOR_NAME, SQLITE_UTF8, collator,
                collate8, (void(*)(void*))localized_collator_dtor);
    }

    if (err != SQLITE_OK) {
        return err;
    }
    //// PHONEBOOK_COLLATOR
#endif //SQLITE_ENABLE_ICU

    return SQLITE_OK;
}


extern "C" int register_android_functions(sqlite3 * handle, int utf16Storage __attribute((unused)))
{
    int err;
#ifdef SQLITE_ENABLE_ICU
    UErrorCode status = U_ZERO_ERROR;

    UCollator * collator = ucol_open(NULL, &status);
    if (U_FAILURE(status)) {
        return -1;
    }

    if (utf16Storage) {
        // Note that text should be stored as UTF-16
        err = sqlite3_exec(handle, "PRAGMA encoding = 'UTF-16'", 0, 0, 0);
        if (err != SQLITE_OK) {
            return err;
        }

        // Register the UNICODE collation
        err = sqlite3_create_collation_v2(handle, "UNICODE", SQLITE_UTF16, collator, collate16,
                (void(*)(void*))localized_collator_dtor);
    } else {
        err = sqlite3_create_collation_v2(handle, "UNICODE", SQLITE_UTF8, collator, collate8,
                (void(*)(void*))localized_collator_dtor);
    }

    if (err != SQLITE_OK) {
        return err;
    }
#endif // SQLITE_ENABLE_ICU

    // Register the PHONE_NUM_EQUALS function
    err = sqlite3_create_function(
        handle, "PHONE_NUMBERS_EQUAL", 2,
        SQLITE_UTF8, NULL, phone_numbers_equal, NULL, NULL);
    if (err != SQLITE_OK) {
        return err;
    }

    // Register the PHONE_NUM_EQUALS function with an additional argument "use_strict"
    err = sqlite3_create_function(
        handle, "PHONE_NUMBERS_EQUAL", 3,
        SQLITE_UTF8, NULL, phone_numbers_equal, NULL, NULL);
    if (err != SQLITE_OK) {
        return err;
    }

    // Register the _DELETE_FILE function
    err = sqlite3_create_function(handle, "_DELETE_FILE", 1, SQLITE_UTF8, NULL, delete_file, NULL, NULL);
    if (err != SQLITE_OK) {
        return err;
    }

#if ENABLE_ANDROID_LOG
    // Register the _LOG function
    err = sqlite3_create_function(handle, "_LOG", 1, SQLITE_UTF8, NULL, android_log, NULL, NULL);
    if (err != SQLITE_OK) {
        return err;
    }
#endif

    // Register the _PHONE_NUMBER_STRIPPED_REVERSED function, which imitates
    // PhoneNumberUtils.getStrippedReversed.  This function is used by
    // packages/providers/ContactsProvider/src/com/android/providers/contacts/LegacyApiSupport.java
    // to provide compatibility with Android 1.6 and earlier.
    err = sqlite3_create_function(handle,
        "_PHONE_NUMBER_STRIPPED_REVERSED",
        1, SQLITE_UTF8, NULL,
        phone_number_stripped_reversed,
        NULL, NULL);
    if (err != SQLITE_OK) {
        return err;
    }

    return SQLITE_OK;
}