#ifndef RVPROF_INTERNAL_H
#define RVPROF_INTERNAL_H

#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <time.h>
#include <unistd.h>
#include "rvprof.h"

#ifdef __cplusplus
extern "C"{
#endif 

// constants
#define INITIAL_FUNCTIONS 128
#define INITIAL_STACKS 256
#define INITIAL_REGIONS 128
#define INITIAL_SYMBOLS 512
#define GROWTH_FACTOR 2
#define MAX_NAME_LEN 64


// error enum
typedef enum {
    RVPROF_SUCCESS = 0,
    RVPROF_ERROR_MEMORY = -1,
    RVPROF_ERROR_IO = -2,
    RVPROF_ERROR_SYMBOLS = -3,
    RVPROF_ERROR_INVALID_STATE = -4,
    RVPROF_ERROR_STACK_OVERFLOW = -5,
    RVPROF_ERROR_STACK_UNDERFLOW = -6
} rvprof_error_t;

// symbol table entry
typedef struct{
    uintptr_t addr;
    char name[MAX_NAME_LEN];
    size_t size;
} symbol_entry_t;

// region stack entry
typedef struct {
    char name[MAX_NAME_LEN];
    uint64_t start_cycles;
    uint64_t start_time_ns;
    int depth;
    int function_id;
    int stack_id;
    uint64_t child_time;
    uint64_t child_cycles;
    void* func_addr;
} region_t;

// function stats
typedef struct {
    char name [MAX_NAME_LEN];
    char caller [MAX_NAME_LEN];
    uint64_t total_inclusive_time;
    uint64_t total_exclusive_time;
    uint64_t total_inclusive_cycles; 
    uint64_t total_exclusive_cycles;
    uint64_t call_count;
    int* stack_ids;
    int num_stack_ids;
    int max_stack_ids;
    char** callers;
    int num_callers;
    int max_callers;
    double exclusive_percent;
    double inclusive_percent;
} function_stats_t;

// stack info
typedef struct {
    char* stack_path;
    int stid;
} stack_info_t;

// dynamic array structure (could switch to a more sophisticated container + template if we would move to C++ at some point)
#define DECLARE_DYNAMIC_ARRAY(type, name) \
typedef struct { \
    type* data; \
    int size; \
    int capacity; \
} name##_array_t;

DECLARE_DYNAMIC_ARRAY(region_t, region);
DECLARE_DYNAMIC_ARRAY(function_stats_t, function_stats);
DECLARE_DYNAMIC_ARRAY(symbol_entry_t, symbol);
DECLARE_DYNAMIC_ARRAY(stack_info_t, stack_info);

// config structure
typedef struct {
    int enable_hooks;
    int merge_regions;
    char* output_filename;
    char* program_name;
} rvprof_config_t;

// global context
typedef struct{
    rvprof_config_t config;
    
    // cycle counter info
    int use_cycles;
    int cycles_avaiable;

    // dynamic arrays
    region_array_t regions;
    function_stats_array_t functions;
    stack_info_array_t stacks;
    symbol_array_t symbols;

    // state
    int initialized;
    int auto_initialized;
    int symbols_loaded;
    int stack_ptr;
    FILE* output_file;

    // statistics
    uint64_t total_program_time;
    uint64_t total_program_cycles;
    size_t total_memory_allocated;
} rvprof_context_t;


// ONLY GLOBAL VARIABLE
extern rvprof_context_t g_rvprof;


// internal API

// memory management
void* rvprof_malloc(size_t size);
void* rvprof_reallovc(void* ptr, size_t old_size, size_t new_size);
void rvprof_free(void* ptr, size_t size);

// dynamic array management
int region_array_ensure_capacity(region_array_t* arr, int needed);
int function_stats_array_ensure_capacity(function_stats_array_t* arr, int needed);
int stack_info_array_ensure_capacity(stack_info_array_t* arr, int needed);
int symbol_array_ensure_capacity(symbol_array_t* arr, int needed);

void region_array_cleanup(region_array_t* arr);
void function_stats_array_cleanup(function_stats_array_t* arr);
void stack_info_array_cleanup(stack_info_array_t* arr);
void symbol_array_cleanup(symbol_array_t* arr);

// memory operations: fyunction statistics
int rvprof_memory_add_stack_id_to_function(int func_id, int stack_id);
int rvprof_memory_add_caller_to_function(int func_id, const char* caller);

// timing
rvprof_error_t rvprof_timing_init(void);
uint64_t rvprof_timing_get_current(void);
uint64_t rvprof_timing_get_cycles(void);
double rvprof_timing_to_seconds(uint64_t nanoseconds);
int rvprof_timing_test_cycle_counter(void);

// symbol resolution
rvprof_error_t rvprof_symbols_init(const char* program_path);
const char* rvprof_symbols_lookup(void* addr);
void rvprof_symbols_cleanup(void);

// function statistics management
int rvprof_stats_find_or_create_function(const char* name, const char* caller);
int rvprof_stats_get_or_create_stack_id(void);
void rvprof_stats_add_stack_id_to_function(int func_id, int stid);
void rvprof_stats_add_caller_to_function(int func_id, const char* caller);

// output 
rvprof_error_t rvprof_output_generate_report(void);

#ifdef __cplusplus
}
#endif

#endif