/*
 hstr_favorites.c       favorite commands

 Copyright (C) 2014-2021  Martin Dvorak <martin.dvorak@mindforger.com>

 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.
*/

#include "include/hstr_favorites.h"

#define FAVORITE_SEGMENT_SIZE 10

void favorites_init(FavoriteItems* favorites)
{
    favorites->items=NULL;
    favorites->count=0;
    favorites->loaded=false;
    favorites->reorderOnChoice=true;
    favorites->skipComments=false;
    favorites->set=malloc(sizeof(HashSet));
    hashset_init(favorites->set);
}

void favorites_show(FavoriteItems *favorites)
{
    printf("\n\nFavorites (%d):", favorites->count);
    if(favorites->count) {
        unsigned i;
        for(i=0; i<favorites->count; i++) {
            printf("\n%s",favorites->items[i]);
        }
    }
    printf("\n");
}

char* favorites_get_filename()
{
    char* home = getenv(ENV_VAR_HOME);
    char* fileName = (char*) malloc(strlen(home) + 1 + strlen(FILE_HSTR_FAVORITES) + 1);
    strcpy(fileName, home);
    strcat(fileName, "/");
    strcat(fileName, FILE_HSTR_FAVORITES);
    return fileName;
}

void favorites_get(FavoriteItems* favorites)
{
    if(!favorites->loaded) {
        char* fileName = favorites_get_filename();
        char* fileContent = NULL;
        if(access(fileName, F_OK) != -1) {
            long inputFileSize;

            FILE* inputFile = fopen(fileName, "rb");
            fseek(inputFile, 0, SEEK_END);
            inputFileSize = ftell(inputFile);
            rewind(inputFile);
            fileContent = malloc((inputFileSize + 1) * (sizeof(char)));
            if(!fread(fileContent, sizeof(char), inputFileSize, inputFile)) {
                if(ferror(inputFile)) {
                    exit(EXIT_FAILURE);
                }
            }
            fclose(inputFile);
            fileContent[inputFileSize] = 0;

            if(fileContent && strlen(fileContent)) {
                favorites->count = 0;
                char* p=strchr(fileContent,'\n');
                while (p!=NULL) {
                    favorites->count++;
                    p=strchr(p+1,'\n');
                }

                favorites->items = malloc(sizeof(char*) * favorites->count);
                favorites->count = 0;
                char* pb=fileContent, *pe, *s;
                pe=strchr(fileContent, '\n');
                while(pe!=NULL) {
                    *pe=0;
                    if(!hashset_contains(favorites->set,pb)) {
                        if(!favorites->skipComments || !(strlen(pb) && pb[0]=='#')) {
                            s=hstr_strdup(pb);
                            favorites->items[favorites->count++]=s;
                            hashset_add(favorites->set,s);
                        }
                    }
                    pb=pe+1;
                    pe=strchr(pb, '\n');
                }
                free(fileContent);
            }
        } else {
            // favorites file not found > favorites don't exist yet
            favorites->loaded=true;
        }
        free(fileName);
    }
}

void favorites_save(FavoriteItems* favorites)
{
    char* fileName=favorites_get_filename();

    if(favorites->count) {
        FILE* outputFile = fopen(fileName, "wb");
        rewind(outputFile);
        unsigned i;
        for(i=0; i<favorites->count; i++) {
            if(!fwrite(favorites->items[i], sizeof(char), strlen(favorites->items[i]), outputFile)) {
                if(ferror(outputFile)) {
                    exit(EXIT_FAILURE);
                }
            }
            if(!fwrite("\n", sizeof(char), strlen("\n"), outputFile)) {
                if(ferror(outputFile)) {
                    exit(EXIT_FAILURE);
                }
            }
        }
        fclose(outputFile);
    } else {
        if(access(fileName, F_OK) != -1) {
            FILE *output_file = fopen(fileName, "wb");
            fclose(output_file);
        }
    }
    free(fileName);
}

void favorites_add(FavoriteItems* favorites, char* newFavorite)
{
    if(favorites->count) {
        favorites->items=realloc(favorites->items, sizeof(char*) * ++favorites->count);
        favorites->items[favorites->count-1]=hstr_strdup(newFavorite);
        favorites_choose(favorites, newFavorite);
    } else {
        favorites->items=malloc(sizeof(char*));
        favorites->items[0]=hstr_strdup(newFavorite);
        favorites->count=1;
    }

    favorites_save(favorites);
    hashset_add(favorites->set, newFavorite);
}

void favorites_choose(FavoriteItems* favorites, char* choice)
{
    if(favorites->reorderOnChoice && favorites->count && choice) {
        unsigned r;
        char* b=NULL, *next;
        for(r=0; r<favorites->count; r++) {
            if(!strcmp(favorites->items[r],choice)) {
                favorites->items[0]=favorites->items[r];
                if(b) {
                    favorites->items[r]=b;
                }
                favorites_save(favorites);
                return;
            }
            next=favorites->items[r];
            favorites->items[r]=b;
            b=next;
        }
    }
}

bool favorites_remove(FavoriteItems* favorites, char* almostDead)
{
    if(favorites->count) {
        int r, w, count;
        count=favorites->count;
        for(r=0, w=0; r<count; r++) {
            if(!strcmp(favorites->items[r], almostDead)) {
                favorites->count--;
            } else {
                if(w<r) {
                    favorites->items[w]=favorites->items[r];
                }
                w++;
            }
        }
        favorites_save(favorites);
        // kept in set and removed/freed on favs destroy
        return true;
    } else {
        return false;
    }
}

void favorites_destroy(FavoriteItems* favorites)
{
    if(favorites) {
        // TODO hashset destroys keys - no need to destroy items!
        unsigned i;
        for(i=0; i<favorites->count; i++) {
            free(favorites->items[i]);
        }
        free(favorites->items);
        hashset_destroy(favorites->set, false);
        free(favorites->set);
        free(favorites);
    }
}
