#!/usr/bin/tcc -run
#include <ctype.h>
#include <dirent.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/wait.h>
#include <unistd.h>

void print_man_dir(FILE *menu, const char *dir) {
    DIR *d = opendir(dir);
    if (!d) {
        return;
    }

    struct dirent *ent;
    while ((ent = readdir(d))) {
        if (ent->d_name[0] == '.') {
            continue;
        }

        char file[512];
        snprintf(file, sizeof(file), "%s", ent->d_name);

        const char *suffixes[] = {".gz", ".bz2", ".xz", ".lzma", ".zst"};
        for (size_t i = 0; i < sizeof(suffixes) / sizeof(suffixes[0]); i++) {
            size_t flen = strlen(file);
            size_t slen = strlen(suffixes[i]);
            if (flen > slen && strcmp(file + flen - slen, suffixes[i]) == 0) {
                file[flen - slen] = '\0';
                break;
            }
        }

        char *dot = strrchr(file, '.');
        if (!dot || dot == file || !dot[1]) {
            continue;
        }

        *dot++ = '\0';
        fprintf(menu, "%s (%s)\tman\n", file, dot);
    }

    closedir(d);
}

void print_man_pages(FILE *menu, const char *root) {
    DIR *d = opendir(root);
    if (!d) {
        return;
    }

    struct dirent *ent;
    char path[4096];
    while ((ent = readdir(d))) {
        if (strncmp(ent->d_name, "man", 3) != 0) {
            continue;
        }

        snprintf(path, sizeof(path), "%s/%s", root, ent->d_name);
        print_man_dir(menu, path);
    }

    closedir(d);
}

int main(void) {
    char path[] = "/tmp/docs-list.XXXXXX";
    int fd = mkstemp(path);
    if (fd < 0) {
        perror("mkstemp");
        return 1;
    }

    FILE *menu = fdopen(fd, "w");
    if (!menu) {
        perror("fdopen");
        unlink(path);
        return 1;
    }

    char line[8192];
    FILE *manpath = popen("manpath 2>/dev/null", "r");
    if (manpath && fgets(line, sizeof(line), manpath)) {
        line[strcspn(line, "\n")] = '\0';
        for (char *dir = strtok(line, ":"); dir; dir = strtok(NULL, ":")) {
            print_man_pages(menu, dir);
        }
    }
    if (manpath) {
        pclose(manpath);
    }

    FILE *pydoc = popen("python -c 'import pkgutil; [print(m) for m in sorted({m.name for m in pkgutil.iter_modules()})]'", "r");
    if (pydoc) {
        while (fgets(line, sizeof(line), pydoc)) {
            line[strcspn(line, "\n")] = '\0';
            fprintf(menu, "%s\tpydoc\n", line);
        }
        pclose(pydoc);
    }

    fclose(menu);

    char command[1024];
    snprintf(command, sizeof(command), "wmenu -i -l 20 < '%s'", path);

    FILE *wmenu = popen(command, "r");
    if (!wmenu) {
        perror("wmenu");
        unlink(path);
        return 1;
    }

    if (!fgets(line, sizeof(line), wmenu)) {
        pclose(wmenu);
        unlink(path);
        return 0;
    }

    int status = pclose(wmenu);
    unlink(path);
    if (status != 0) {
        return WIFEXITED(status) ? WEXITSTATUS(status) : 1;
    }

    line[strcspn(line, "\n")] = '\0';
    char *kind = strrchr(line, '\t');
    if (!kind) {
        return 0;
    }
    *kind++ = '\0';

    if (strcmp(kind, "man") == 0) {
        char *s = line;
        char name[256] = {0};
        char section[64] = {0};
        size_t i = 0;

        while (*s && !isspace((unsigned char)*s) && *s != '(' && i < sizeof(name) - 1) {
            name[i++] = *s++;
        }

        char *open = strchr(s, '(');
        char *close = open ? strchr(open + 1, ')') : NULL;
        if (open && close && close > open + 1) {
            size_t len = close - open - 1;
            if (len >= sizeof(section)) {
                len = sizeof(section) - 1;
            }
            memcpy(section, open + 1, len);
        }

        if (name[0] && section[0]) {
            execlp("foot", "foot", "-e", "man", section, name, NULL);
        } else if (name[0]) {
            execlp("foot", "foot", "-e", "man", name, NULL);
        }
    } else if (strcmp(kind, "pydoc") == 0 && line[0]) {
        execlp("foot", "foot", "-e", "python", "-m", "pydoc", line, NULL);
    }

    perror("foot");
    return 1;
}