#define _POSIX_C_SOURCE 200809L 
#define _XOPEN_SOURCE 700
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "libmbpk.h"
#include "ini.h"
#include <sys/stat.h>
#include <curl/curl.h>
#include <ftw.h>

#define MBPK_DB_DIR "/var/lib/mbpk"
#define MBPK_REPO_DIR "/var/lib/mbpk-repo"
#define MBPK_REPO_CONFIG "/etc/mbpk-repos.ini"
#define MAX_REPOS 32

typedef struct {
	const char *name;
	const char *desc;
	const char *url;
	char **packages;
} mbpk_repository;

struct curl_memory {
	char* memory;
	size_t size;
};

mbpk_repository *repos[MAX_REPOS];
int repo_count = 0;

static int unlink_cb(const char *fpath, const struct stat *sb, int typeflag, struct FTW *ftwbuf) {
	int rv;

	/* silence, compiler */
	(void)sb;
	(void)typeflag;
	(void)ftwbuf;

	rv = remove(fpath);
	if (rv) {
		perror(fpath);
	}
	return rv;
}

int rm_rf(const char *path) {
	return nftw(path, unlink_cb, 64, FTW_DEPTH | FTW_PHYS);
}

/* static char* strdup(const char *s) {
	size_t size = strlen(s) + 1;
	char* p = (char*)malloc(size);
	if (p) {
		memcpy(p, s, size);
	}
	return p;
} */

static char **split_string(const char *str) {
	char *str_copy;
	char *token;
	char **result;
	int count;
	int i;

	count = 0;

	if (!str || !*str) {
		return NULL;
	}

	str_copy = strdup(str);
	if (!str_copy) {
		return NULL;
	}

	token = strtok(str_copy, " ");
	while (token) {
		count++;
		token = strtok(NULL, " ");
	}
	free(str_copy);
	
	if (count == 0) {
		return NULL;
	}

	result = malloc((unsigned long)(count + 1) * sizeof(char*));
	if (!result) {
		return NULL;
	}

	str_copy = strdup(str);
	if (!str_copy) {
		free(result);
		return NULL;
	}

	token = strtok(str_copy, " ");
	i = 0;
	while (token) {
		result[i] = strdup(token);
		if (!result[i]) {
			while (i > 0) {
				free((void*)result[--i]);
			}
			free(result);
			free(str_copy);
			return NULL;
		}
		i++;
		token = strtok(NULL, " ");
	}
	result[count] = NULL;
	free(str_copy);
	return result;
}

static void free_split_array(char **arr) {
	int i;
	if (!arr) {
		return;
	}

	for (i = 0; arr[i] != NULL; i++) {
		free((void*)arr[i]);
	}
	free(arr);
}

static size_t curl_memory_write_calback(void *contents, size_t size, size_t nmemb, void *userp) {
	size_t realsize = size * nmemb;
	struct curl_memory *mem = (struct curl_memory*)userp;

	char *ptr = realloc(mem->memory, mem->size + realsize + 1);
	if (!ptr) {
		return 0;
	}

	mem->memory = ptr;
	memcpy(&(mem->memory[mem->size]), contents, realsize);
	mem->size += realsize;
	mem->memory[mem->size] = 0;

	return realsize;
}

int mbpk_init(void) {
	CURLcode result;
	struct stat st;
	if (stat(MBPK_DB_DIR, &st) == -1) {
		if (mkdir(MBPK_DB_DIR, 0755) == -1) {
			return MBPK_DB_FAIL;
		}
	}
	if (stat(MBPK_REPO_DIR, &st) == -1) {
		if (mkdir(MBPK_REPO_DIR, 0755) == -1) {
			return MBPK_REPO_FAIL;
		}
	}
	result = curl_global_init(CURL_GLOBAL_ALL);
	if (result != CURLE_OK) {
		return MBPK_CURL_INIT_FAIL;
	}
	return MBPK_OK;
}

static int repo_conf_handler(void* user, const char* section, const char* name, const char* value) {
	/* SHUT UP COMPILER AAAAAAAAAAAAA */
	(void)user;

	if (!(strcmp(name, "url") == 0)) {
		return 0; /* unknown name, error */
	}

	if (repo_count >= MAX_REPOS) {
		return 0; /* too many repos */
	}

	repos[repo_count] = malloc(sizeof(mbpk_repository));
	if (repos[repo_count] == NULL) {
		return 0; /* out of memory */
	}

	repos[repo_count]->name = strdup(section);
	repos[repo_count]->desc = NULL; /* mbpk_update_repositories will fill this in later */
	repos[repo_count]->url = strdup(value);
	repos[repo_count]->packages = NULL; /* mbpk_update_repositories will fill this in later */

	if (repos[repo_count]->name == NULL || repos[repo_count]->url == NULL) {
		free((void*)repos[repo_count]->name);
		free((void*)repos[repo_count]->url);
		free(repos[repo_count]);
		repos[repo_count] = NULL;
		return 0; /* out of memory */
	}

	repo_count++;
	return 1;
}

static int repo_ini_handler(void *user, const char *section, const char *name, const char *value) {
	mbpk_repository *repo;

	/* SILENCE YOU COMPILER */
	(void)section;
	
	repo = (mbpk_repository*)user;

	if (strcmp(name, "name") == 0) {
		free((void*)repo->name);
		repo->name = strdup(value);
	} else if (strcmp(name, "url") == 0) {
		free((void*)repo->url);
		repo->url = strdup(value);
	} else if (strcmp(name, "desc") == 0) {
		free((void*)repo->desc);
		repo->desc = strdup(value);
	} else if (strcmp(name, "packages") == 0) {	
		/* Do stuff here */
		if (repo->packages) {
			free_split_array(repo->packages);
		}
		repo->packages = split_string(value);
	} 

	return 1;
}

int mbpk_update_repositories(void) {
	/* Declarations */
	struct stat st;
	int i;
	mbpk_repository *repo;
	CURL *curl;
	CURLcode result;
	char *repo_ini_url;
	char *repo_ini_path;
	char *repo_dir;
	char *pkg_ini_url;
	char *pkg_dir;
	size_t dir_len;
	size_t repo_ini_path_len;
	size_t pkg_ini_url_len;
	size_t pkg_dir_len;
	FILE *fp;
	struct curl_memory chunk;

	repo_count = 0;
	if (ini_parse(MBPK_REPO_CONFIG, repo_conf_handler, NULL) < 0) {
		return MBPK_REPO_FAIL;
	}

	for (i = 0; i < repo_count; i++) {
		repo = repos[i];
		printf("[libmbpk debug] processing repo %s\n", repo->name);
		chunk.memory = malloc(1);
		if (!chunk.memory) {
			return MBPK_OUT_OF_MEMORY;
		}
		chunk.size = 0;

		curl = curl_easy_init();
		if (curl) {
			repo_ini_url = malloc(strlen(repo->url) + strlen("/repo.ini") + 1);
			if (!repo_ini_url) {
				return MBPK_OUT_OF_MEMORY;
			}
			strcpy(repo_ini_url, repo->url);
			strcat(repo_ini_url, "/repo.ini");
			printf("[libmbpk debug] URL: %s\n", repo_ini_url);
			printf("[libmbpk debug] repo url field: %s\n", repo->url);
			curl_easy_setopt(curl, CURLOPT_URL, repo_ini_url);
			curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L); /* follow redirects */
			curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_memory_write_calback);
			curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void*)&chunk);
			curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1L); /* fail on errors like 404 */
			curl_easy_setopt(curl, CURLOPT_ACCEPT_ENCODING, ""); /* accept encoding like gzip */

			result = curl_easy_perform(curl);
			curl_easy_cleanup(curl);
			free(repo_ini_url);

			if (result != CURLE_OK) {
				printf("[libmbpk debug] perform cURL failed\n");
				free(chunk.memory);
				return MBPK_CURL_PERFORM_FAIL;
			} else {
				printf("[libmbpk debug] %lu bytes received\n", (unsigned long)chunk.size);
				printf("[libmbpk debug] Response:\n%s\n", chunk.memory);
			}
		} else {
			free(chunk.memory);
			return MBPK_CURL_INIT_FAIL;
		}
		
		dir_len = strlen(MBPK_REPO_DIR) + 1 + strlen(repo->name) + 1;
		repo_dir = malloc(dir_len);
		if (!repo_dir) {
			free(chunk.memory);
			return MBPK_OUT_OF_MEMORY;
		}
		sprintf(repo_dir, "%s/%s", MBPK_REPO_DIR, repo->name);

		repo_ini_path_len = strlen(repo_dir) + 1 + strlen("repo.ini") + 1;
		repo_ini_path = malloc(repo_ini_path_len);
		if (!repo_ini_path) {
			free(chunk.memory);
			free(repo_dir);
			return MBPK_OUT_OF_MEMORY;
		}
		sprintf(repo_ini_path, "%s/repo.ini", repo_dir);

		if (stat(repo_dir, &st) == -1) {
			if (mkdir(repo_dir, 0755) == -1) {
				free(chunk.memory);
				free(repo_ini_path);
				free(repo_dir);
				return MBPK_REPO_FAIL;
			} 
		}

		fp = fopen(repo_ini_path, "w");
		if (!fp) {
			free(repo_ini_path);
			free(repo_dir);
			free(chunk.memory);
			return MBPK_REPO_FAIL;
		}
		fwrite(chunk.memory, 1, chunk.size, fp);
		fclose(fp);
		free(chunk.memory);

		if (ini_parse(repo_ini_path, repo_ini_handler, (void*)repo) < 0) {
			free(repo_ini_path);
			return MBPK_REPO_FAIL;
		}
		free(repo_ini_path);
		printf("[libmbpk debug] repo %s desc: %s\n", repo->name, repo->desc);
		printf("[libmbpk debug] repo %s packages:\n", repo->name);

		pkg_dir_len = strlen(repo_dir) + 1 + strlen("pkg") + 1;
		pkg_dir = malloc(pkg_dir_len);
		if (!pkg_dir) {
			return MBPK_OUT_OF_MEMORY;
		}
		sprintf(pkg_dir, "%s/pkg", repo_dir);

		if (stat(pkg_dir, &st) == -1) {
			printf("[libmbpk debug] removing old pkg directory for %s\n", repo->name);
			if (rm_rf(pkg_dir) != 0) {
				free(pkg_dir);
				free(repo_dir);
				return MBPK_REPO_FAIL;
			}
		}

		for (i = 0; repo->packages[i] != NULL; i++) {
			chunk.memory = malloc(1);
			if (!chunk.memory) {
				free(pkg_dir);
				free(repo_dir);
				return MBPK_OUT_OF_MEMORY;
			}
			chunk.size = 0; /* oh fuck, thats why this didnt work - i was overwriting broken shit */
			printf(" %s\n", repo->packages[i]);
			curl = curl_easy_init();
			if (curl) {
				pkg_ini_url_len = strlen(repo->url) + 1 + strlen("pkg") + 1 + strlen(repo->packages[i]) + strlen(".ini") + 1;
				pkg_ini_url = malloc(pkg_ini_url_len);
				if (!pkg_ini_url) {
					free(repo_dir);
					return MBPK_OUT_OF_MEMORY;
				}
				sprintf(pkg_ini_url, "%s/pkg/%s.ini", repo->url, repo->packages[i]);
				curl_easy_setopt(curl, CURLOPT_URL, pkg_ini_url);
				curl_easy_setopt(curl, CURLOPT_FOLLOWLOCATION, 1L); /* follow redirects */
				curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, curl_memory_write_calback);
				curl_easy_setopt(curl, CURLOPT_WRITEDATA, (void*)&chunk);
				curl_easy_setopt(curl, CURLOPT_FAILONERROR, 1L); /* fail on errors like 404 */
				curl_easy_setopt(curl, CURLOPT_ACCEPT_ENCODING, ""); /* accept encoding like gzip */

				result = curl_easy_perform(curl);
				curl_easy_cleanup(curl);
				free(pkg_ini_url);

				if (result != CURLE_OK) {
					printf("[libmbpk debug] perform cURL failed\n");
					free(chunk.memory);
					free(pkg_dir);
					free(repo_dir);
					return MBPK_CURL_PERFORM_FAIL;
				} else {
					printf("[libmbpk debug] %lu bytes received\n", (unsigned long)chunk.size);
					printf("[libmbpk debug] Response:\n%s\n", chunk.memory);
				}
			} else {
				free(chunk.memory);
				free(repo_dir);
				free(pkg_dir);
				return MBPK_CURL_INIT_FAIL;
			}

			free(chunk.memory);
			free(pkg_dir);
			free(repo_dir);
		}
	}

	return MBPK_OK;
}

void mbpk_cleanup(void) {	
	int i;
	for (i = 0; i < repo_count; i++) {
		if (repos[i]) {
			free((void*)repos[i]->name);
			free((void*)repos[i]->url);
			free((void*)repos[i]->desc);
			free((void*)repos[i]->packages);
			free((void*)repos[i]);
			repos[i] = NULL;
		}
	}
	repo_count = 0;
	curl_global_cleanup();
}

const char* mbpk_strerr(int code) {
	const char* strerr;
	switch (code) {
		case MBPK_OK:
			strerr = "MBPK_OK (0)";
			break;
		case MBPK_DB_FAIL:
			strerr = "MBPK_DB_FAIL (1)";
			break;
		case MBPK_REPO_FAIL:
			strerr = "MBPK_REPO_FAIL (2)";
			break;
		case MBPK_DL_FAIL:
			strerr = "MBPK_DL_FAIL (3)";
			break;
		case MBPK_EXTRACT_FAIL:
			strerr = "MBPK_EXTRACT_FAIL (4)";
			break;
		case MBPK_CURL_INIT_FAIL:
			strerr = "MBPK_CURL_INIT_FAIL (5)";
			break;
		case MBPK_CURL_PERFORM_FAIL:
			strerr = "MBPK_CURL_PERFORM_FAIL (6)";
			break;
		case MBPK_OUT_OF_MEMORY:
			strerr = "MBPK_OUT_OF_MEMORY (7)";
			break;
		default:
			strerr = "MBPK_UNKNOWN_ERR";
			break;
	}
	return strerr;
}