#include <ncurses.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "editor.h"
#include "log.h"

void help() {
    printf("Usage:\n");
    printf("    cmd open <file/path> // opens the specified file\n");
    printf("    cmd rm <file/path> // deletes the specified file\n");
    printf("    cmd new <file/path> // creates a new empty file at the specified path\n");
    printf("    cmd mv <old/path> <new/path> // moves the specified file to the new path\n");
    printf("    cmd cp <old/path> <new/path> // copies the specified file to the new path\n");
    printf("    cmd lenl <file/path> // returns the length of the specified file in lines\n");
    printf("    cmd lenc <file/path> // returns the length of the specified file in chars\n");
    printf("    cmd log // prints a list of all changes made to the file\n");
}

int open_editor(char* filename) {
    initscr();
    raw();
    noecho();
    keypad(stdscr, true);
    int max_y, max_x;
    getmaxyx(stdscr, max_y, max_x);

    start_color();
    use_default_colors();

    init_pair(1, COLOR_CYAN, -1);
    init_pair(2, COLOR_MAGENTA, -1);

    move(0, 5);

    Editor editor;
    if (strcmp(filename, "") == 0) {
        editor = new_editor(str_from_chars(filename));    
    } else {
        editor = editor_from(str_from_file(fopen(filename, "r")), str_from_chars(filename));
    }
    while (true) {
        refresh();
        int c = getch();
        if (editor.editmode == true) {
            switch (c) {
                case 27:
                    switch_mode(&editor);
                    break;
                case KEY_BACKSPACE:
                    move_cursor(&editor, -1, 0);
                    delchar(&editor);
                    break;
                case KEY_DC:
                    delchar(&editor);
                    break;
                case '\n':
                    pressed_enter(&editor);
                    break;
                case KEY_UP:
                    move_cursor(&editor, 0, -1);
                    break;
                case KEY_DOWN:
                    move_cursor(&editor, 0, 1);
                    break;
                case KEY_LEFT:
                    move_cursor(&editor, -1, 0);
                    break;
                case KEY_RIGHT:
                    move_cursor(&editor, 1, 0);
                    break;
                default:
                    addchar(&editor, c);
                    break;
            }
        } else {
            switch (c) {
                case 'q':
                    endwin();
                    shutdown_editor(&editor);

                    return 0;
                case 'i':
                    switch_mode(&editor);
                    break;
                case 'w':
                    editor.unsaved_changes = false;
                    save_file(&editor);
                    // TODO: write function to save the data to a file
                    break;
                default:
                    break;
            }
        }
    }
}

// Copies a file from source to destination
int copy_file(const char* source, const char* dest) {
    FILE* src = fopen(source, "rb");
    if (src == NULL) {
        fprintf(stderr, "Error: Could not open source file %s\n", source);
        return -1;
    }

    FILE* dst = fopen(dest, "wb");
    if (dst == NULL) {
        fclose(src);
        fprintf(stderr, "Error: Could not create destination file %s\n", dest);
        return -1;
    }

    char buffer[8192];
    size_t bytes;
    while ((bytes = fread(buffer, 1, sizeof(buffer), src)) > 0) {
        if (fwrite(buffer, 1, bytes, dst) != bytes) {
            fclose(src);
            fclose(dst);
            fprintf(stderr, "Error: Write failed to %s\n", dest);
            return -1;
        }
    }

    fclose(src);
    fclose(dst);
    return 0;
}

// Counts the number of characters in a file
int count_chars(const char* filename) {
    FILE* file = fopen(filename, "r");
    if (file == NULL) {
        fprintf(stderr, "Error: Could not open file %s\n", filename);
        return -1;
    }

    int count = 0;
    int ch;
    while ((ch = fgetc(file)) != EOF) {
        count++;
    }

    fclose(file);
    return count;
}

// Counts the number of lines in a file
int count_lines(const char* filename) {
    FILE* file = fopen(filename, "r");
    if (file == NULL) {
        fprintf(stderr, "Error: Could not open file %s\n", filename);
        return -1;
    }

    int count = 0;
    int ch;
    int last_char = '\n';  // Handle empty files as 0 lines

    while ((ch = fgetc(file)) != EOF) {
        if (ch == '\n') {
            count++;
        }
        last_char = ch;
    }

    // Count last line if it doesn't end with newline
    if (last_char != '\n' && last_char != EOF) {
        count++;
    }

    fclose(file);
    return count;
}

// Command types
typedef enum {
    CMD_OPEN,
    CMD_RM,
    CMD_NEW,
    CMD_MV,
    CMD_CP,
    CMD_LENL,
    CMD_LENC,
    CMD_LOG,
    CMD_UNKNOWN
} CommandType;

// Convert string to command type
CommandType str_to_cmd(const char* cmd) {
    if (strcmp(cmd, "open") == 0) return CMD_OPEN;
    if (strcmp(cmd, "rm") == 0) return CMD_RM;
    if (strcmp(cmd, "new") == 0) return CMD_NEW;
    if (strcmp(cmd, "mv") == 0) return CMD_MV;
    if (strcmp(cmd, "cp") == 0) return CMD_CP;
    if (strcmp(cmd, "lenl") == 0) return CMD_LENL;
    if (strcmp(cmd, "lenc") == 0) return CMD_LENC;
    if (strcmp(cmd, "log") == 0) return CMD_LOG;
    return CMD_UNKNOWN;
}

int main(int argc, char* argv[]) {
    char log_fmt_string[128];

    if (argc < 2) {
        help();
        return 1;
    }

    CommandType cmd = str_to_cmd(argv[1]);

    if (argc == 3) {
        switch (cmd) {
            case CMD_OPEN:
                sprintf(log_fmt_string, "Opened File [%s]", argv[2]);
                open_editor(argv[2]);
                break;
            case CMD_RM:
                remove(argv[2]);
                sprintf(log_fmt_string, "Deleted File [%s]", argv[2]);
                break;
            case CMD_NEW:
                sprintf(log_fmt_string, "Created File [%s]", argv[2]);
                open_editor(argv[2]);
                break;
            case CMD_LENC:
                printf("%d\n", count_chars(argv[2]));
                break;
            case CMD_LENL:
                printf("%d\n", count_lines(argv[2]));
                break;
            default:
                help();
        }
    } 
    
    else if (argc == 4) {
        switch (cmd) {
            case CMD_MV:    
                if (rename(argv[2], argv[3]) != 0) {
                    fprintf(stderr, "Error: Failed to move file %s to %s\n", argv[2], argv[3]);
                } else {
                    sprintf(log_fmt_string, "Moved file [%s] To [%s]", argv[2], argv[3]);
                }
                break;
            case CMD_CP:
                if (copy_file(argv[2], argv[3]) != 0) {
                    fprintf(stderr, "Error: Failed to copy file %s to %s\n", argv[2], argv[3]);
                    sprintf(log_fmt_string, "Failed to copy file [%s] To [%s]", argv[2], argv[3]);
                } else {
                    sprintf(log_fmt_string, "Copied file [%s] To [%s]", argv[2], argv[3]);
                }
                break;
            default:
                help();
        }
    } 
    
    else {
        printf("invalid options\n");
        help();
    }

    // log output of command
    if (log_fmt_string[0] != '\0') {
        String_t str = str_from_chars(log_fmt_string);
        write_log(&str);
        str_dealloc(&str);
    }
   
    return 0;
}