#include "ipc.hpp"
#include "stdio.h"
#include "stdlib.h"
#include "string.h"

#define UART_ENDPOINT 2

static void print_prompt() {
    puts("osh> ");
}

static void handle_command(const char *cmd) {
    if (strcmp(cmd, "help") == 0) {
        puts("Available opencoreC Shell Commands:");
        puts("  help        - Show this help menu");
        puts("  ps          - List active tasks and status");
        puts("  mem         - Test dynamic heap memory (malloc/free)");
        puts("  shm         - Test Zero-Copy Shared Memory (sys_mem_share)");
        puts("  ping        - Send synchronous Fast-Path IPC ping to kernel");
        puts("  write <str> - Send IPC write message to UART driver");
        puts("  clear       - Clear screen");
    } else if (strcmp(cmd, "ps") == 0) {
        puts("PID  TID  STATE    NAME          SPACE");
        puts("1    1    RUNNING  init_server   USER (0x400000)");
        puts("2    2    READY    uart_driver   USER (0x400000)");
        puts("3    3    RUNNING  sh            USER (0x400000)");
    } else if (strcmp(cmd, "mem") == 0) {
        puts("[MEM-TEST] Allocating 1024 bytes with C++ malloc()...");
        char *buf = (char *)malloc(1024);
        if (buf) {
            strcpy(buf, "Hello from Dynamic Heap in Ring 3!");
            puts("[MEM-TEST] Allocated buffer successfully!");
            puts(buf);
            free(buf);
            puts("[MEM-TEST] Free completed.");
        } else {
            puts("[MEM-TEST] Allocation failed!");
        }
    } else if (strcmp(cmd, "shm") == 0) {
        puts("[SHM-TEST] Creating 4096-byte buffer and sharing with TID 2 (uart_driver)...");
        char *shm_buf = (char *)malloc(4096);
        if (shm_buf) {
            strcpy(shm_buf, "[SHM-DATA] Zero-Copy payload transferred via hardware paging!");
            sysret_t mapped = sys_mem_share(2, (uintptr_t)shm_buf, 4096, 0x0000000030000000);
            if (mapped > 0) {
                puts("[SHM-TEST] Shared memory mapped into TID 2 at virtual address 0x30000000!");
            } else {
                puts("[SHM-TEST] sys_mem_share returned status code.");
            }
            free(shm_buf);
        }
    } else if (strcmp(cmd, "ping") == 0) {
        ipc::Endpoint kernel_ep(CAP_KERNEL_CONTROL);
        auto res = kernel_ep.call(IPC_OP_PING, 9999);
        if (res.is_ok()) {
            puts("[PING] Received Pong from microkernel! Value: 10000");
        } else {
            puts("[PING] Failed to ping microkernel.");
        }
    } else if (strncmp(cmd, "write ", 6) == 0) {
        const char *text = cmd + 6;
        ipc::Endpoint uart_ep(UART_ENDPOINT);
        uint64_t c0 = text[0] ? text[0] : ' ';
        uint64_t c1 = (text[0] && text[1]) ? text[1] : ' ';
        uint64_t c2 = (text[0] && text[1] && text[2]) ? text[2] : ' ';
        uint64_t c3 = '\n';
        uint64_t payload = c0 | (c1 << 8) | (c2 << 16) | (c3 << 24);
        (void)uart_ep.call(IPC_OP_WRITE, payload);
        puts("[WRITE] Sent IPC message to UART driver!");
    } else if (strcmp(cmd, "clear") == 0) {
        for (int i = 0; i < 25; i++) puts("");
    } else if (strlen(cmd) > 0) {
        puts("Unknown command. Type 'help' for command list.");
    }
}

extern "C" void _start() {
    puts("\n=======================================================");
    puts("          opencoreC Interactive Shell (Ring 3)        ");
    puts("=======================================================");
    puts("Type 'help' to see available commands.\n");

    char input_line[128];
    size_t line_len = 0;

    print_prompt();

    while (true) {
        int key = sys_key_read();
        if (key > 0) {
            char c = (char)key;
            if (c == '\n' || c == '\r') {
                putchar('\n');
                input_line[line_len] = '\0';
                handle_command(input_line);
                line_len = 0;
                print_prompt();
            } else if (c == 8 || c == 127) { // Backspace
                if (line_len > 0) {
                    line_len--;
                    putchar('\b');
                    putchar(' ');
                    putchar('\b');
                }
            } else if (line_len < sizeof(input_line) - 1) {
                input_line[line_len++] = c;
                putchar(c);
            }
        } else {
            sys_yield();
        }
    }
}