#ifndef CST_TOOLS_H
#define CST_TOOLS_H

#include "cst_agent.h"

#ifdef __cplusplus
extern "C" {
#endif

#define CST_TOOL_MAX_PARAMS 6
#define CST_TOOL_MAX_TARGETS 16

/* Up to max workspace-relative regular files (ignores .git, node_modules,
 * root .gitignore ...). Caller frees each entry and the array. */
int cst_workspace_files(const char *ws, char ***out, int max);

/* What a call can touch; drives confirmation, undo and duplicate-read logic. */
typedef enum {
  CST_TP_READ = 0, /* reads the workspace */
  CST_TP_WRITE,    /* changes files (snapshotted for /undo) */
  CST_TP_SHELL,    /* arbitrary commands */
  CST_TP_NET,      /* network access */
  CST_TP_ASK,      /* talks to the user */
  CST_TP_META      /* agent bookkeeping (todo list) */
} cst_tool_perm_t;

typedef struct {
  const char *name;
  const char *type; /* "string" | "integer" | "boolean" */
  int required;
  const char *desc;
} cst_tool_param_t;

typedef struct cst_tool_ctx {
  const char *workspace_root;
  /* ask_user: fills ans; returns 0, or -1 when nobody can answer. */
  int (*ask)(const char *question, const char *options, char *ans,
             size_t ans_sz, void *ud);
  void *ask_ud;
  /* todo_write: the list was replaced (text form, one item per line). */
  void (*set_todo)(const char *text, void *ud);
  void *todo_ud;
  int sandbox; /* run_shell: confine to the workspace (cst_sandbox.h) */
} cst_tool_ctx_t;

typedef int (*cst_tool_run_fn)(const cst_tool_ctx_t *ctx,
                               const ctl_tool_call_t *call,
                               cst_tool_result_t *r);
/* Write tools: compute the diff a call would produce without touching disk.
 * Returns 0 and a malloc'd text, or -1 with an error text in *out. */
typedef int (*cst_tool_preview_fn)(const cst_tool_ctx_t *ctx,
                                   const ctl_tool_call_t *call, char **out);

typedef struct {
  const char *name;
  const char *desc;
  /* `--tools minimal` schema text (the original wording; required params
   * only), so paper runs keep sending byte-identical requests. */
  const char *min_desc;
  cst_tool_param_t params[CST_TOOL_MAX_PARAMS];
  cst_tool_perm_t perm;
  int minimal; /* member of `--tools minimal` (the original four) */
  cst_tool_run_fn run;
  cst_tool_preview_fn preview;
} cst_tool_def_t;

typedef enum { CST_TOOLS_DEFAULT = 0, CST_TOOLS_MINIMAL } cst_tool_profile_t;

int cst_tool_profile_parse(const char *s, int *out);
const char *cst_tool_profile_name(int p);

int cst_tool_count(void);
const cst_tool_def_t *cst_tool_at(int i);
const cst_tool_def_t *cst_tool_find(const char *name);
int cst_tool_index(const char *name);

/* Enabled for this config (profile + /tools switches). cfg may be NULL. */
int cst_tool_active(const cst_agent_config_t *cfg, const cst_tool_def_t *t);
/* OpenAI tools[] for the active set (cJSON*, caller frees). */
void *cst_tools_schema_cfg(const cst_agent_config_t *cfg);
/* "Tools:\n- name(a, b?): ...\n" for the active set (malloc'd). */
char *cst_tools_prompt(const cst_agent_config_t *cfg);
/* Comma-separated active tool names (malloc'd). */
char *cst_tools_names(const cst_agent_config_t *cfg);

/* Missing required args / bad integers. 0 = ok. */
int cst_tool_validate(const cst_tool_def_t *t, const ctl_tool_call_t *call,
                      char *err, size_t err_sz);
int cst_tool_run(const cst_tool_ctx_t *ctx, const ctl_tool_call_t *call,
                 cst_tool_result_t *r);
int cst_tool_preview(const cst_tool_ctx_t *ctx, const ctl_tool_call_t *call,
                     char **out);

/* Workspace-relative files a write call may change (for /undo snapshots).
 * Returns the count written into paths. */
int cst_tool_targets(const ctl_tool_call_t *call, char paths[][1024], int max);

/* Unified diff (3 lines of context, GNU `diff -u` layout) with
 * `--- a/<label>` / `+++ b/<label>` headers. Returns malloc'd text; "" when
 * identical. */
char *cst_diff_unified(const char *label, const char *a, size_t alen,
                       const char *b, size_t blen);

#ifdef __cplusplus
}
#endif

#endif