#include "editor.h"
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <libgen.h>

static char statusmsg[256];

static void load_desc(Editor *e)
{
    e->desc[0] = '\0';
    if (!e->buf.filename) return;
    char tmp[512];
    strncpy(tmp, e->buf.filename, sizeof(tmp) - 1);
    tmp[sizeof(tmp) - 1] = '\0';
    char *dir = dirname(tmp);
    char path[512];
    snprintf(path, sizeof(path), "%s/desc.txt", dir);
    FILE *f = fopen(path, "r");
    if (!f) return;
    int pos = 0;
    int c;
    while ((c = fgetc(f)) != EOF && pos < (int)sizeof(e->desc) - 1)
        e->desc[pos++] = (char)c;
    e->desc[pos] = '\0';
    fclose(f);
}

void editor_init(Editor *e)
{
    buf_init(&e->buf);
    e->cx = e->cy = 0;
    e->rowoff = e->coloff = 0;
    e->mode = MODE_NORMAL;
    e->ft = FT_NONE;
    e->ghost[0] = '\0';
    e->idle_count = 0;
    e->nano_mode = 0;
    e->cutbuf = (Line){NULL, 0, 0};
    e->desc[0] = '\0';
    e->autocomplete_row = -1;
    e->autocomplete_col = 0;
    getmaxyx(stdscr, e->screenrows, e->screencols);
    e->screenrows -= 2; /* reserve status + command line */
    statusmsg[0] = '\0';
}

void editor_open(Editor *e, const char *filename)
{
    buf_load(&e->buf, filename);
    e->ft = syntax_detect(filename);
    load_desc(e);
}

void editor_scroll(Editor *e)
{
    if (e->cy < e->rowoff)
        e->rowoff = e->cy;
    if (e->cy >= e->rowoff + e->screenrows)
        e->rowoff = e->cy - e->screenrows + 1;
    if (e->cx < e->coloff)
        e->coloff = e->cx;
    if (e->cx >= e->coloff + e->screencols)
        e->coloff = e->cx - e->screencols + 1;
}

void editor_set_status(Editor *e, const char *fmt, ...)
{
    (void)e;
    va_list ap;
    va_start(ap, fmt);
    vsnprintf(statusmsg, sizeof(statusmsg), fmt, ap);
    va_end(ap);
}

void editor_draw(Editor *e)
{
    editor_scroll(e);
    erase();

    if (e->nano_mode) {
        /* nano layout: title bar row 0, content rows 1..screenrows,
           status at screenrows+1, shortcut bars at screenrows+2..+3 */
        int content_start = 1;
        for (int y = 0; y < e->screenrows; y++) {
            int filerow = y + e->rowoff;
            int sy = y + content_start;
            if (filerow < e->buf.numlines) {
                Line *l = &e->buf.lines[filerow];
                int len = l->len - e->coloff;
                if (len < 0) len = 0;
                if (len > e->screencols) len = e->screencols;
                if (len > 0 && l->chars) {
                    if (e->ft != FT_NONE) {
                        int bc = syntax_line_in_block_comment(
                                     &e->buf, filerow, e->ft);
                        syntax_draw_line(l->chars + e->coloff, len,
                                         sy, 0, e->screencols, e->ft, bc);
                    } else {
                        mvaddnstr(sy, 0, l->chars + e->coloff, len);
                    }
                }
            }
        }

        /* ghost text */
        if (e->ghost[0] != '\0') {
            int gy = e->cy - e->rowoff + content_start;
            int gx = e->cx - e->coloff;
            if (gy > 0 && gy <= e->screenrows && gx >= 0) {
                attron(A_DIM);
                int glen = (int)strlen(e->ghost);
                if (gx + glen > e->screencols) glen = e->screencols - gx;
                if (glen > 0) mvaddnstr(gy, gx, e->ghost, glen);
                attroff(A_DIM);
            }
        }

        /* status message line */
        if (statusmsg[0])
            mvaddnstr(e->screenrows + 1, 0, statusmsg, e->screencols);

        /* nano title bar + shortcut bars */
        nano_draw_bars(e);

        /* cursor */
        move(e->cy - e->rowoff + content_start, e->cx - e->coloff);
    } else {
        /* vi layout */
        for (int y = 0; y < e->screenrows; y++) {
            int filerow = y + e->rowoff;
            if (filerow < e->buf.numlines) {
                Line *l = &e->buf.lines[filerow];
                int len = l->len - e->coloff;
                if (len < 0) len = 0;
                if (len > e->screencols) len = e->screencols;
                if (len > 0 && l->chars) {
                    if (e->ft != FT_NONE) {
                        int bc = syntax_line_in_block_comment(
                                     &e->buf, filerow, e->ft);
                        syntax_draw_line(l->chars + e->coloff, len,
                                         y, 0, e->screencols, e->ft, bc);
                    } else {
                        mvaddnstr(y, 0, l->chars + e->coloff, len);
                    }
                }
            } else {
                mvaddch(y, 0, '~');
            }
        }

        /* ghost text */
        if (e->mode == MODE_INSERT && e->ghost[0] != '\0') {
            int gy = e->cy - e->rowoff;
            int gx = e->cx - e->coloff;
            if (gy >= 0 && gy < e->screenrows && gx >= 0) {
                attron(A_DIM);
                int glen = (int)strlen(e->ghost);
                if (gx + glen > e->screencols) glen = e->screencols - gx;
                if (glen > 0) mvaddnstr(gy, gx, e->ghost, glen);
                attroff(A_DIM);
            }
        }

        /* status bar */
        attron(A_REVERSE);
        char status[256];
        const char *modestr = e->mode == MODE_INSERT ? "-- INSERT --" :
                              e->mode == MODE_COMMAND ? ":" : "";
        const char *fname = e->buf.filename ? e->buf.filename : "[No Name]";
        int slen = snprintf(status, sizeof(status), " %s %s%s",
                            modestr, fname, e->buf.dirty ? " [+]" : "");
        char rinfo[64];
        int rlen = snprintf(rinfo, sizeof(rinfo), "%d/%d ",
                            e->cy + 1, e->buf.numlines);
        for (int i = slen; i < e->screencols - rlen; i++)
            status[i] = ' ';
        memcpy(status + e->screencols - rlen, rinfo, rlen);
        status[e->screencols] = '\0';
        mvaddnstr(e->screenrows, 0, status, e->screencols);
        attroff(A_REVERSE);

        /* message/command line */
        mvaddnstr(e->screenrows + 1, 0, statusmsg, e->screencols);

        /* cursor */
        move(e->cy - e->rowoff, e->cx - e->coloff);
    }

    refresh();
}

void editor_prompt_desc(Editor *e)
{
    int row = e->nano_mode ? e->screenrows + 1 : e->screenrows + 1;
    char buf[sizeof(e->desc)];
    int len = 0;

    /* pre-fill with current desc */
    if (e->desc[0]) {
        len = (int)strlen(e->desc);
        memcpy(buf, e->desc, len);
    }
    buf[len] = '\0';

    editor_set_status(e, "Desc: %s", buf);
    editor_draw(e);
    move(row, 6 + len);
    refresh();

    for (;;) {
        int c = getch();
        if (c == '\r' || c == '\n' || c == KEY_ENTER) break;
        if (c == 27) { return; } /* ESC cancels */
        if ((c == KEY_BACKSPACE || c == 127) && len > 0) {
            buf[--len] = '\0';
        } else if (c >= 32 && c < 127 && len < (int)sizeof(buf) - 1) {
            buf[len++] = (char)c;
            buf[len] = '\0';
        }
        editor_set_status(e, "Desc: %s", buf);
        editor_draw(e);
        move(row, 6 + len);
        refresh();
    }

    memcpy(e->desc, buf, len);
    e->desc[len] = '\0';
    editor_set_status(e, len > 0 ? "[Description set]" : "[Description cleared]");
}