#include "enrichers.h"

#include <algorithm>
#include <cctype>
#include <cstdio>
#include <cstring>
#include <dirent.h>
#include <fstream>
#include <sstream>
#include <sys/stat.h>

namespace ge {

namespace {

std::vector<EnricherSpec> g_enrichers;

std::string strip(const std::string& s) {
    size_t a = 0, b = s.size();
    while (a < b && std::isspace((unsigned char)s[a])) ++a;
    while (b > a && std::isspace((unsigned char)s[b - 1])) --b;
    return s.substr(a, b - a);
}

std::string strip_quotes(const std::string& s) {
    if (s.size() >= 2) {
        if ((s.front() == '"' && s.back() == '"') ||
            (s.front() == '\'' && s.back() == '\'')) {
            return s.substr(1, s.size() - 2);
        }
    }
    return s;
}

std::string lower(std::string s) {
    for (auto& c : s) c = (char)std::tolower((unsigned char)c);
    return s;
}

// Parsea una lista inline `[a, b, c]` o "[Webpage, Url]". Tolerante a
// espacios y a comillas simples/dobles dentro. NO soporta listas
// multi-linea — el manifest las usa siempre inline.
std::vector<std::string> parse_inline_list(const std::string& v) {
    std::vector<std::string> out;
    std::string s = strip(v);
    if (s.size() < 2 || s.front() != '[' || s.back() != ']') return out;
    s = s.substr(1, s.size() - 2);
    std::string token;
    auto flush = [&]() {
        std::string t = strip_quotes(strip(token));
        if (!t.empty()) out.push_back(std::move(t));
        token.clear();
    };
    for (char c : s) {
        if (c == ',') flush();
        else token.push_back(c);
    }
    flush();
    return out;
}

// Manifest YAML soportado (subset):
//   id: fetch_webpage
//   name: "Fetch web page"
//   description: "..."
//   applies_to: [Webpage, Url]
//   params:                          <- v1 ignora bloque
//     - { name: timeout_s, ... }
//
// Las claves anidadas bajo `params:` se ignoran (saltamos lineas indentadas).
bool parse_manifest(const std::string& path, EnricherSpec* out) {
    std::ifstream f(path);
    if (!f) return false;
    std::string line;
    bool in_skip_block = false;
    while (std::getline(f, line)) {
        // Strip CR de Windows.
        if (!line.empty() && line.back() == '\r') line.pop_back();

        // Linea blanca o comentario.
        std::string trim = strip(line);
        if (trim.empty() || trim.front() == '#') continue;

        // Si la linea NO empieza con whitespace, salimos del bloque skip.
        bool indented = !line.empty() && std::isspace((unsigned char)line.front());
        if (!indented) in_skip_block = false;
        if (in_skip_block) continue;

        size_t colon = trim.find(':');
        if (colon == std::string::npos) continue;

        std::string key = strip(trim.substr(0, colon));
        std::string val = strip(trim.substr(colon + 1));

        if (key == "id")               out->id = strip_quotes(val);
        else if (key == "name")        out->name = strip_quotes(val);
        else if (key == "description") out->description = strip_quotes(val);
        else if (key == "applies_to")  out->applies_to = parse_inline_list(val);
        else if (key == "params" && val.empty()) in_skip_block = true;
        // emits/relations los ignoramos en v1 (solo informativos).
    }
    return !out->id.empty();
}

} // namespace

int enrichers_load(const char* enrichers_dir) {
    g_enrichers.clear();
    if (!enrichers_dir || !*enrichers_dir) return -1;

    // En Windows los UNC paths esperan backslashes consistentes; mixed
    // separators (`\\wsl$\<distro>\foo/bar`) confunden a opendir de MinGW.
    std::string dir = enrichers_dir;
#ifdef _WIN32
    for (char& c : dir) if (c == '/') c = '\\';
#endif

    DIR* d = opendir(dir.c_str());
    if (!d) {
        std::fprintf(stderr, "[enrichers] opendir failed: %s\n", dir.c_str());
        return -1;
    }

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

#ifdef _WIN32
        const char sep = '\\';
#else
        const char sep = '/';
#endif
        std::string sub = dir + sep + ent->d_name;
        struct stat st{};
        if (stat(sub.c_str(), &st) != 0 || !S_ISDIR(st.st_mode)) continue;

        std::string manifest = sub + sep + "manifest.yaml";
        std::string runpy    = sub + sep + "run.py";
        if (stat(manifest.c_str(), &st) != 0) continue;
        if (stat(runpy.c_str(),    &st) != 0) continue;

        EnricherSpec spec;
        if (!parse_manifest(manifest, &spec)) {
            std::fprintf(stderr, "[enrichers] parse failed: %s\n", manifest.c_str());
            continue;
        }
        spec.run_path = runpy;
        g_enrichers.push_back(std::move(spec));
    }
    closedir(d);

    std::sort(g_enrichers.begin(), g_enrichers.end(),
              [](const EnricherSpec& a, const EnricherSpec& b) {
                  return a.name < b.name;
              });
    return (int)g_enrichers.size();
}

const std::vector<EnricherSpec>& enrichers_all() {
    return g_enrichers;
}

std::vector<EnricherSpec> enrichers_for_type(const char* type_ref) {
    std::vector<EnricherSpec> out;
    if (!type_ref || !*type_ref) return out;
    std::string want = lower(type_ref);
    for (const auto& e : g_enrichers) {
        if (e.applies_to.empty()) {
            out.push_back(e);
            continue;
        }
        for (const auto& t : e.applies_to) {
            if (lower(t) == want) { out.push_back(e); break; }
        }
    }
    return out;
}

const EnricherSpec* enricher_by_id(const char* id) {
    if (!id || !*id) return nullptr;
    for (const auto& e : g_enrichers) {
        if (e.id == id) return &e;
    }
    return nullptr;
}

} // namespace ge