#define _POSIX_C_SOURCE 200809L

#include "tools.h"

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <limits.h>

#include "cjson/cJSON.h"
#include "nostr_handler.h"

static char* json_error(const char* msg) {
    cJSON* root = cJSON_CreateObject();
    if (!root) return NULL;
    cJSON_AddBoolToObject(root, "success", 0);
    cJSON_AddStringToObject(root, "error", msg ? msg : "unknown error");
    char* out = cJSON_PrintUnformatted(root);
    cJSON_Delete(root);
    return out;
}

static char* json_success_with_message(const char* msg) {
    cJSON* root = cJSON_CreateObject();
    if (!root) return NULL;
    cJSON_AddBoolToObject(root, "success", 1);
    cJSON_AddStringToObject(root, "message", msg ? msg : "ok");
    char* out = cJSON_PrintUnformatted(root);
    cJSON_Delete(root);
    return out;
}

static int is_safe_relative_path(const char* path) {
    if (!path || path[0] == '\0') return 0;
    if (path[0] == '/') return 0;
    if (strstr(path, "..") != NULL) return 0;
    if (strchr(path, '\\') != NULL) return 0;
    return 1;
}

static int build_tool_path(tools_context_t* ctx, const char* rel_path, char* out, size_t out_size) {
    if (!ctx || !ctx->cfg || !rel_path || !out || out_size == 0) return -1;
    if (!is_safe_relative_path(rel_path)) return -1;

    const char* cwd = ctx->cfg->tools.shell.working_directory[0] != '\0'
                          ? ctx->cfg->tools.shell.working_directory
                          : ".";

    int n = 0;
    if (strcmp(cwd, ".") == 0) {
        n = snprintf(out, out_size, "%s", rel_path);
    } else {
        n = snprintf(out, out_size, "%s/%s", cwd, rel_path);
    }

    if (n < 0 || (size_t)n >= out_size) return -1;
    return 0;
}

int tools_init(tools_context_t* ctx, didactyl_config_t* cfg) {
    if (!ctx || !cfg) return -1;
    memset(ctx, 0, sizeof(*ctx));
    ctx->cfg = cfg;
    return 0;
}

void tools_cleanup(tools_context_t* ctx) {
    if (!ctx) return;
    memset(ctx, 0, sizeof(*ctx));
}

char* tools_build_openai_schema_json(const tools_context_t* ctx) {
    (void)ctx;

    cJSON* tools = cJSON_CreateArray();
    if (!tools) return NULL;

    cJSON* t1 = cJSON_CreateObject();
    cJSON* t1_fn = cJSON_CreateObject();
    cJSON* t1_params = cJSON_CreateObject();
    cJSON* t1_props = cJSON_CreateObject();
    cJSON* t1_required = cJSON_CreateArray();

    cJSON_AddStringToObject(t1, "type", "function");
    cJSON_AddStringToObject(t1_fn, "name", "nostr_post");
    cJSON_AddStringToObject(t1_fn, "description", "Publish a Nostr event to connected relays");
    cJSON_AddStringToObject(t1_params, "type", "object");
    cJSON_AddItemToObject(t1_params, "properties", t1_props);
    cJSON_AddItemToObject(t1_params, "required", t1_required);

    cJSON* p_kind = cJSON_CreateObject();
    cJSON_AddStringToObject(p_kind, "type", "integer");
    cJSON_AddItemToObject(t1_props, "kind", p_kind);
    cJSON* p_content = cJSON_CreateObject();
    cJSON_AddStringToObject(p_content, "type", "string");
    cJSON_AddItemToObject(t1_props, "content", p_content);
    cJSON_AddItemToArray(t1_required, cJSON_CreateString("kind"));
    cJSON_AddItemToArray(t1_required, cJSON_CreateString("content"));

    cJSON_AddItemToObject(t1_fn, "parameters", t1_params);
    cJSON_AddItemToObject(t1, "function", t1_fn);
    cJSON_AddItemToArray(tools, t1);

    cJSON* t2 = cJSON_CreateObject();
    cJSON* t2_fn = cJSON_CreateObject();
    cJSON* t2_params = cJSON_CreateObject();
    cJSON* t2_props = cJSON_CreateObject();
    cJSON* t2_required = cJSON_CreateArray();

    cJSON_AddStringToObject(t2, "type", "function");
    cJSON_AddStringToObject(t2_fn, "name", "nostr_query");
    cJSON_AddStringToObject(t2_fn, "description", "Query events from relays using a Nostr filter");
    cJSON_AddStringToObject(t2_params, "type", "object");
    cJSON_AddItemToObject(t2_params, "properties", t2_props);
    cJSON_AddItemToObject(t2_params, "required", t2_required);

    cJSON* p_filter = cJSON_CreateObject();
    cJSON_AddStringToObject(p_filter, "type", "object");
    cJSON_AddItemToObject(t2_props, "filter", p_filter);
    cJSON* p_timeout = cJSON_CreateObject();
    cJSON_AddStringToObject(p_timeout, "type", "integer");
    cJSON_AddItemToObject(t2_props, "timeout_ms", p_timeout);
    cJSON_AddItemToArray(t2_required, cJSON_CreateString("filter"));

    cJSON_AddItemToObject(t2_fn, "parameters", t2_params);
    cJSON_AddItemToObject(t2, "function", t2_fn);
    cJSON_AddItemToArray(tools, t2);

    cJSON* t3 = cJSON_CreateObject();
    cJSON* t3_fn = cJSON_CreateObject();
    cJSON* t3_params = cJSON_CreateObject();
    cJSON* t3_props = cJSON_CreateObject();
    cJSON* t3_required = cJSON_CreateArray();

    cJSON_AddStringToObject(t3, "type", "function");
    cJSON_AddStringToObject(t3_fn, "name", "shell_exec");
    cJSON_AddStringToObject(t3_fn, "description", "Execute a shell command and return stdout/stderr");
    cJSON_AddStringToObject(t3_params, "type", "object");
    cJSON_AddItemToObject(t3_params, "properties", t3_props);
    cJSON_AddItemToObject(t3_params, "required", t3_required);

    cJSON* p_cmd = cJSON_CreateObject();
    cJSON_AddStringToObject(p_cmd, "type", "string");
    cJSON_AddItemToObject(t3_props, "command", p_cmd);
    cJSON_AddItemToArray(t3_required, cJSON_CreateString("command"));

    cJSON_AddItemToObject(t3_fn, "parameters", t3_params);
    cJSON_AddItemToObject(t3, "function", t3_fn);
    cJSON_AddItemToArray(tools, t3);

    cJSON* t4 = cJSON_CreateObject();
    cJSON* t4_fn = cJSON_CreateObject();
    cJSON* t4_params = cJSON_CreateObject();
    cJSON* t4_props = cJSON_CreateObject();
    cJSON* t4_required = cJSON_CreateArray();

    cJSON_AddStringToObject(t4, "type", "function");
    cJSON_AddStringToObject(t4_fn, "name", "file_read");
    cJSON_AddStringToObject(t4_fn, "description", "Read a local file as text from the configured working directory");
    cJSON_AddStringToObject(t4_params, "type", "object");
    cJSON_AddItemToObject(t4_params, "properties", t4_props);
    cJSON_AddItemToObject(t4_params, "required", t4_required);

    cJSON* p_fr_path = cJSON_CreateObject();
    cJSON_AddStringToObject(p_fr_path, "type", "string");
    cJSON_AddItemToObject(t4_props, "path", p_fr_path);
    cJSON* p_fr_max = cJSON_CreateObject();
    cJSON_AddStringToObject(p_fr_max, "type", "integer");
    cJSON_AddItemToObject(t4_props, "max_bytes", p_fr_max);
    cJSON_AddItemToArray(t4_required, cJSON_CreateString("path"));

    cJSON_AddItemToObject(t4_fn, "parameters", t4_params);
    cJSON_AddItemToObject(t4, "function", t4_fn);
    cJSON_AddItemToArray(tools, t4);

    cJSON* t5 = cJSON_CreateObject();
    cJSON* t5_fn = cJSON_CreateObject();
    cJSON* t5_params = cJSON_CreateObject();
    cJSON* t5_props = cJSON_CreateObject();
    cJSON* t5_required = cJSON_CreateArray();

    cJSON_AddStringToObject(t5, "type", "function");
    cJSON_AddStringToObject(t5_fn, "name", "file_write");
    cJSON_AddStringToObject(t5_fn, "description", "Write text content to a local file in the configured working directory");
    cJSON_AddStringToObject(t5_params, "type", "object");
    cJSON_AddItemToObject(t5_params, "properties", t5_props);
    cJSON_AddItemToObject(t5_params, "required", t5_required);

    cJSON* p_fw_path = cJSON_CreateObject();
    cJSON_AddStringToObject(p_fw_path, "type", "string");
    cJSON_AddItemToObject(t5_props, "path", p_fw_path);
    cJSON* p_fw_content = cJSON_CreateObject();
    cJSON_AddStringToObject(p_fw_content, "type", "string");
    cJSON_AddItemToObject(t5_props, "content", p_fw_content);
    cJSON* p_fw_append = cJSON_CreateObject();
    cJSON_AddStringToObject(p_fw_append, "type", "boolean");
    cJSON_AddItemToObject(t5_props, "append", p_fw_append);
    cJSON_AddItemToArray(t5_required, cJSON_CreateString("path"));
    cJSON_AddItemToArray(t5_required, cJSON_CreateString("content"));

    cJSON_AddItemToObject(t5_fn, "parameters", t5_params);
    cJSON_AddItemToObject(t5, "function", t5_fn);
    cJSON_AddItemToArray(tools, t5);

    char* out = cJSON_PrintUnformatted(tools);
    cJSON_Delete(tools);
    return out;
}

static char* execute_nostr_post(const char* args_json) {
    cJSON* args = cJSON_Parse(args_json ? args_json : "{}");
    if (!args) return json_error("invalid arguments JSON");

    cJSON* kind = cJSON_GetObjectItemCaseSensitive(args, "kind");
    cJSON* content = cJSON_GetObjectItemCaseSensitive(args, "content");
    if (!kind || !cJSON_IsNumber(kind) || !content || !cJSON_IsString(content) || !content->valuestring) {
        cJSON_Delete(args);
        return json_error("nostr_post requires integer kind and string content");
    }

    int rc = nostr_handler_publish_kind_event((int)kind->valuedouble, content->valuestring, NULL);
    cJSON_Delete(args);
    if (rc != 0) return json_error("nostr_post failed");

    return json_success_with_message("nostr_post published");
}

static char* execute_nostr_query(const char* args_json) {
    cJSON* args = cJSON_Parse(args_json ? args_json : "{}");
    if (!args) return json_error("invalid arguments JSON");

    cJSON* filter = cJSON_GetObjectItemCaseSensitive(args, "filter");
    cJSON* timeout = cJSON_GetObjectItemCaseSensitive(args, "timeout_ms");
    if (!filter || !cJSON_IsObject(filter)) {
        cJSON_Delete(args);
        return json_error("nostr_query requires object filter");
    }

    cJSON* filter_dup = cJSON_Duplicate(filter, 1);
    if (!filter_dup) {
        cJSON_Delete(args);
        return json_error("failed to duplicate filter");
    }

    int timeout_ms = (timeout && cJSON_IsNumber(timeout)) ? (int)timeout->valuedouble : 8000;
    char* events_json = nostr_handler_query_json(filter_dup, timeout_ms);
    cJSON_Delete(filter_dup);
    cJSON_Delete(args);

    if (!events_json) return json_error("nostr_query failed");

    cJSON* out = cJSON_CreateObject();
    if (!out) {
        free(events_json);
        return NULL;
    }

    cJSON* events = cJSON_Parse(events_json);
    free(events_json);
    if (!events) {
        cJSON_Delete(out);
        return json_error("nostr_query returned invalid JSON");
    }

    cJSON_AddBoolToObject(out, "success", 1);
    cJSON_AddItemToObject(out, "events", events);
    char* json = cJSON_PrintUnformatted(out);
    cJSON_Delete(out);
    return json;
}

static char* execute_shell_exec(tools_context_t* ctx, const char* args_json) {
    if (!ctx || !ctx->cfg) return json_error("tool context unavailable");
    if (!ctx->cfg->tools.shell.enabled) return json_error("shell tool disabled");

    cJSON* args = cJSON_Parse(args_json ? args_json : "{}");
    if (!args) return json_error("invalid arguments JSON");

    cJSON* command = cJSON_GetObjectItemCaseSensitive(args, "command");
    if (!command || !cJSON_IsString(command) || !command->valuestring) {
        cJSON_Delete(args);
        return json_error("shell_exec requires string command");
    }

    const char* cwd = ctx->cfg->tools.shell.working_directory[0] != '\0'
                          ? ctx->cfg->tools.shell.working_directory
                          : ".";
    int timeout_s = ctx->cfg->tools.shell.timeout_seconds > 0 ? ctx->cfg->tools.shell.timeout_seconds : 30;

    char cmd[4096];
    snprintf(cmd,
             sizeof(cmd),
             "cd %s && timeout %ds sh -lc %s 2>&1",
             cwd,
             timeout_s,
             command->valuestring);

    FILE* fp = popen(cmd, "r");
    cJSON_Delete(args);
    if (!fp) return json_error("failed to execute command");

    int max_bytes = ctx->cfg->tools.shell.max_output_bytes > 0 ? ctx->cfg->tools.shell.max_output_bytes : 65536;
    char* output = (char*)calloc((size_t)max_bytes + 1U, 1U);
    if (!output) {
        pclose(fp);
        return json_error("allocation failure");
    }

    size_t used = 0;
    while (!feof(fp) && used < (size_t)max_bytes) {
        size_t n = fread(output + used, 1, (size_t)max_bytes - used, fp);
        used += n;
        if (n == 0) break;
    }

    int status = pclose(fp);

    cJSON* out = cJSON_CreateObject();
    if (!out) {
        free(output);
        return NULL;
    }

    cJSON_AddBoolToObject(out, "success", status == 0 ? 1 : 0);
    cJSON_AddNumberToObject(out, "exit_status", status);
    cJSON_AddStringToObject(out, "output", output);
    free(output);

    char* json = cJSON_PrintUnformatted(out);
    cJSON_Delete(out);
    return json;
}

static char* execute_file_read(tools_context_t* ctx, const char* args_json) {
    if (!ctx || !ctx->cfg) return json_error("tool context unavailable");

    cJSON* args = cJSON_Parse(args_json ? args_json : "{}");
    if (!args) return json_error("invalid arguments JSON");

    cJSON* path = cJSON_GetObjectItemCaseSensitive(args, "path");
    cJSON* maxb = cJSON_GetObjectItemCaseSensitive(args, "max_bytes");
    if (!path || !cJSON_IsString(path) || !path->valuestring) {
        cJSON_Delete(args);
        return json_error("file_read requires string path");
    }

    int hard_max = ctx->cfg->tools.shell.max_output_bytes > 0 ? ctx->cfg->tools.shell.max_output_bytes : 65536;
    int max_bytes = (maxb && cJSON_IsNumber(maxb)) ? (int)maxb->valuedouble : hard_max;
    if (max_bytes <= 0 || max_bytes > hard_max) max_bytes = hard_max;

    char file_path[PATH_MAX];
    if (build_tool_path(ctx, path->valuestring, file_path, sizeof(file_path)) != 0) {
        cJSON_Delete(args);
        return json_error("file_read path is not allowed");
    }

    FILE* fp = fopen(file_path, "rb");
    cJSON_Delete(args);
    if (!fp) return json_error("file_read failed to open file");

    char* buf = (char*)calloc((size_t)max_bytes + 1U, 1U);
    if (!buf) {
        fclose(fp);
        return json_error("allocation failure");
    }

    size_t n = fread(buf, 1, (size_t)max_bytes, fp);
    int truncated = !feof(fp) ? 1 : 0;
    fclose(fp);
    buf[n] = '\0';

    cJSON* out = cJSON_CreateObject();
    if (!out) {
        free(buf);
        return NULL;
    }

    cJSON_AddBoolToObject(out, "success", 1);
    cJSON_AddStringToObject(out, "path", file_path);
    cJSON_AddNumberToObject(out, "bytes_read", (double)n);
    cJSON_AddBoolToObject(out, "truncated", truncated);
    cJSON_AddStringToObject(out, "content", buf);
    free(buf);

    char* json = cJSON_PrintUnformatted(out);
    cJSON_Delete(out);
    return json;
}

static char* execute_file_write(tools_context_t* ctx, const char* args_json) {
    if (!ctx || !ctx->cfg) return json_error("tool context unavailable");

    cJSON* args = cJSON_Parse(args_json ? args_json : "{}");
    if (!args) return json_error("invalid arguments JSON");

    cJSON* path = cJSON_GetObjectItemCaseSensitive(args, "path");
    cJSON* content = cJSON_GetObjectItemCaseSensitive(args, "content");
    cJSON* append = cJSON_GetObjectItemCaseSensitive(args, "append");
    if (!path || !cJSON_IsString(path) || !path->valuestring ||
        !content || !cJSON_IsString(content) || !content->valuestring) {
        cJSON_Delete(args);
        return json_error("file_write requires string path and content");
    }

    char file_path[PATH_MAX];
    if (build_tool_path(ctx, path->valuestring, file_path, sizeof(file_path)) != 0) {
        cJSON_Delete(args);
        return json_error("file_write path is not allowed");
    }

    const char* content_str = content->valuestring;
    size_t len = strlen(content_str);
    int do_append = (append && cJSON_IsBool(append) && cJSON_IsTrue(append)) ? 1 : 0;

    FILE* fp = fopen(file_path, do_append ? "ab" : "wb");
    cJSON_Delete(args);
    if (!fp) return json_error("file_write failed to open file");

    size_t n = fwrite(content_str, 1, len, fp);
    fclose(fp);
    if (n != len) return json_error("file_write failed to write all bytes");

    cJSON* out = cJSON_CreateObject();
    if (!out) return NULL;
    cJSON_AddBoolToObject(out, "success", 1);
    cJSON_AddStringToObject(out, "path", file_path);
    cJSON_AddNumberToObject(out, "bytes_written", (double)n);
    cJSON_AddBoolToObject(out, "append", do_append);
    char* json = cJSON_PrintUnformatted(out);
    cJSON_Delete(out);
    return json;
}

char* tools_execute(tools_context_t* ctx, const char* tool_name, const char* args_json) {
    if (!tool_name) return json_error("missing tool name");

    if (strcmp(tool_name, "nostr_post") == 0) {
        return execute_nostr_post(args_json);
    }
    if (strcmp(tool_name, "nostr_query") == 0) {
        return execute_nostr_query(args_json);
    }
    if (strcmp(tool_name, "shell_exec") == 0) {
        return execute_shell_exec(ctx, args_json);
    }
    if (strcmp(tool_name, "file_read") == 0) {
        return execute_file_read(ctx, args_json);
    }
    if (strcmp(tool_name, "file_write") == 0) {
        return execute_file_write(ctx, args_json);
    }

    return json_error("unknown tool");
}