#include "cli_addon_manifest_catalog.hpp"
#include "cli_arg_parse.hpp"
#include "cli_box_emitter.hpp"

#include "pipeline/wowee_addon_manifest.hpp"
#include <nlohmann/json.hpp>

#include <algorithm>
#include <cstdint>
#include <cstdio>
#include <cstring>
#include <fstream>
#include <functional>
#include <map>
#include <set>
#include <string>
#include <vector>

namespace wowee {
namespace editor {
namespace cli {

namespace {

std::string stripWmodExt(std::string base) {
    stripExt(base, ".wmod");
    return base;
}

bool saveOrError(const wowee::pipeline::WoweeAddonManifest& c,
                 const std::string& base, const char* cmd) {
    if (!wowee::pipeline::WoweeAddonManifestLoader::save(c, base)) {
        std::fprintf(stderr, "%s: failed to save %s.wmod\n",
                     cmd, base.c_str());
        return false;
    }
    return true;
}

void printGenSummary(const wowee::pipeline::WoweeAddonManifest& c,
                     const std::string& base) {
    std::printf("Wrote %s.wmod\n", base.c_str());
    std::printf("  catalog : %s\n", c.name.c_str());
    std::printf("  addons  : %zu\n", c.entries.size());
}

int handleGenStandard(int& i, int argc, char** argv) {
    std::string base = argv[++i];
    std::string name = "StandardAddons";
    if (parseOptArg(i, argc, argv)) name = argv[++i];
    base = stripWmodExt(base);
    auto c = wowee::pipeline::WoweeAddonManifestLoader::
        makeStandardAddons(name);
    if (!saveOrError(c, base, "gen-mod")) return 1;
    printGenSummary(c, base);
    return 0;
}

int handleGenUI(int& i, int argc, char** argv) {
    std::string base = argv[++i];
    std::string name = "UIReplacement";
    if (parseOptArg(i, argc, argv)) name = argv[++i];
    base = stripWmodExt(base);
    auto c = wowee::pipeline::WoweeAddonManifestLoader::
        makeUIReplacement(name);
    if (!saveOrError(c, base, "gen-mod-ui")) return 1;
    printGenSummary(c, base);
    return 0;
}

int handleGenUtility(int& i, int argc, char** argv) {
    std::string base = argv[++i];
    std::string name = "UtilityAddons";
    if (parseOptArg(i, argc, argv)) name = argv[++i];
    base = stripWmodExt(base);
    auto c = wowee::pipeline::WoweeAddonManifestLoader::
        makeUtility(name);
    if (!saveOrError(c, base, "gen-mod-util")) return 1;
    printGenSummary(c, base);
    return 0;
}

int handleInfo(int& i, int argc, char** argv) {
    std::string base = argv[++i];
    bool jsonOut = consumeJsonFlag(i, argc, argv);
    base = stripWmodExt(base);
    if (!wowee::pipeline::WoweeAddonManifestLoader::exists(base)) {
        std::fprintf(stderr, "WMOD not found: %s.wmod\n", base.c_str());
        return 1;
    }
    auto c = wowee::pipeline::WoweeAddonManifestLoader::load(base);
    if (jsonOut) {
        nlohmann::json j;
        j["wmod"] = base + ".wmod";
        j["name"] = c.name;
        j["count"] = c.entries.size();
        nlohmann::json arr = nlohmann::json::array();
        for (const auto& e : c.entries) {
            arr.push_back({
                {"addonId", e.addonId},
                {"name", e.name},
                {"description", e.description},
                {"version", e.version},
                {"author", e.author},
                {"minClientBuild", e.minClientBuild},
                {"requiresSavedVariables",
                    e.requiresSavedVariables != 0},
                {"loadOnDemand", e.loadOnDemand != 0},
                {"dependencies", e.dependencies},
                {"optionalDependencies", e.optionalDependencies},
            });
        }
        j["entries"] = arr;
        std::printf("%s\n", j.dump(2).c_str());
        return 0;
    }
    std::printf("WMOD: %s.wmod\n", base.c_str());
    std::printf("  catalog : %s\n", c.name.c_str());
    std::printf("  addons  : %zu\n", c.entries.size());
    if (c.entries.empty()) return 0;
    std::printf("    id  version    sv  lod  deps  optDeps  name\n");
    for (const auto& e : c.entries) {
        std::printf("  %4u  %-9s  %s   %s   %4zu  %7zu  %s\n",
                    e.addonId, e.version.c_str(),
                    e.requiresSavedVariables ? "Y" : "n",
                    e.loadOnDemand ? "Y" : "n",
                    e.dependencies.size(),
                    e.optionalDependencies.size(),
                    e.name.c_str());
    }
    return 0;
}

// Stack-based DFS cycle detection. Returns the first
// cycle found as a vector of addonIds. Empty if no
// cycle. Considers ONLY required dependencies — optional
// deps don't deadlock.
std::vector<uint32_t> findFirstCycle(
    const wowee::pipeline::WoweeAddonManifest& c) {
    std::map<uint32_t, std::vector<uint32_t>> graph;
    std::set<uint32_t> known;
    for (const auto& e : c.entries) {
        graph[e.addonId] = e.dependencies;
        known.insert(e.addonId);
    }
    enum Color : uint8_t { White = 0, Gray = 1, Black = 2 };
    std::map<uint32_t, Color> color;
    for (uint32_t id : known) color[id] = White;
    std::vector<uint32_t> path;
    std::vector<uint32_t> cycle;
    std::function<bool(uint32_t)> dfs = [&](uint32_t node) -> bool {
        color[node] = Gray;
        path.push_back(node);
        for (uint32_t dep : graph[node]) {
            if (!known.count(dep)) continue;
            if (color[dep] == Gray) {
                // Found back-edge to gray node — extract
                // the cycle starting at dep in path.
                auto it = std::find(path.begin(), path.end(), dep);
                cycle.assign(it, path.end());
                cycle.push_back(dep);   // close the loop
                return true;
            }
            if (color[dep] == White) {
                if (dfs(dep)) return true;
            }
        }
        color[node] = Black;
        path.pop_back();
        return false;
    };
    for (uint32_t id : known) {
        if (color[id] == White && dfs(id)) return cycle;
    }
    return {};
}

int handleValidate(int& i, int argc, char** argv) {
    std::string base = argv[++i];
    bool jsonOut = consumeJsonFlag(i, argc, argv);
    base = stripWmodExt(base);
    if (!wowee::pipeline::WoweeAddonManifestLoader::exists(base)) {
        std::fprintf(stderr,
            "validate-wmod: WMOD not found: %s.wmod\n",
            base.c_str());
        return 1;
    }
    auto c = wowee::pipeline::WoweeAddonManifestLoader::load(base);
    std::vector<std::string> errors;
    std::vector<std::string> warnings;
    if (c.entries.empty()) {
        warnings.push_back("catalog has zero entries");
    }
    std::set<uint32_t> idsSeen;
    std::set<std::string> namesSeen;
    std::set<uint32_t> knownIds;
    for (const auto& e : c.entries) knownIds.insert(e.addonId);
    for (size_t k = 0; k < c.entries.size(); ++k) {
        const auto& e = c.entries[k];
        std::string ctx = "entry " + std::to_string(k) +
                          " (id=" + std::to_string(e.addonId);
        if (!e.name.empty()) ctx += " " + e.name;
        ctx += ")";
        if (e.addonId == 0)
            errors.push_back(ctx + ": addonId is 0");
        if (e.name.empty())
            errors.push_back(ctx + ": name is empty");
        if (e.version.empty())
            errors.push_back(ctx + ": version is empty "
                "(every addon must declare a version)");
        if (!e.name.empty() &&
            !namesSeen.insert(e.name).second) {
            errors.push_back(ctx +
                ": duplicate addon name '" + e.name +
                "' — addon-loader would dispatch ambiguously");
        }
        if (!idsSeen.insert(e.addonId).second) {
            errors.push_back(ctx + ": duplicate addonId");
        }
        // Self-dependency: addon listing itself in its
        // own deps would deadlock during load.
        for (uint32_t dep : e.dependencies) {
            if (dep == e.addonId) {
                errors.push_back(ctx +
                    ": addon depends on itself "
                    "(deadlock at load)");
            }
            if (!knownIds.count(dep)) {
                errors.push_back(ctx +
                    ": required dependency addonId=" +
                    std::to_string(dep) +
                    " not found in catalog");
            }
        }
        for (uint32_t dep : e.optionalDependencies) {
            if (dep == e.addonId) {
                warnings.push_back(ctx +
                    ": addon optionally depends on "
                    "itself — has no effect, prune");
            }
            // Optional deps to unknown ids are NOT an
            // error — addon may degrade gracefully if
            // the optional dep is absent.
        }
        if (e.minClientBuild != 0 && e.minClientBuild < 4500) {
            warnings.push_back(ctx +
                ": minClientBuild=" +
                std::to_string(e.minClientBuild) +
                " is below the lowest known WoW vanilla "
                "build (4500); likely a typo");
        }
    }
    // DFS cycle detection over required dependencies.
    auto cycle = findFirstCycle(c);
    if (!cycle.empty()) {
        std::string trail;
        for (size_t k = 0; k < cycle.size(); ++k) {
            if (k > 0) trail += " -> ";
            trail += std::to_string(cycle[k]);
        }
        errors.push_back("dependency cycle detected: " +
                          trail +
                          " — addon-loader would deadlock");
    }
    bool ok = errors.empty();
    if (jsonOut) {
        nlohmann::json j;
        j["wmod"] = base + ".wmod";
        j["ok"] = ok;
        j["errors"] = errors;
        j["warnings"] = warnings;
        std::printf("%s\n", j.dump(2).c_str());
        return ok ? 0 : 1;
    }
    std::printf("validate-wmod: %s.wmod\n", base.c_str());
    if (ok && warnings.empty()) {
        std::printf("  OK — %zu addons, all addonIds + "
                    "names unique, no required-dep cycle, "
                    "no missing required deps, no self-"
                    "deps\n", c.entries.size());
        return 0;
    }
    if (!warnings.empty()) {
        std::printf("  warnings (%zu):\n", warnings.size());
        for (const auto& w : warnings)
            std::printf("    - %s\n", w.c_str());
    }
    if (!errors.empty()) {
        std::printf("  ERRORS (%zu):\n", errors.size());
        for (const auto& e : errors)
            std::printf("    - %s\n", e.c_str());
    }
    return ok ? 0 : 1;
}

} // namespace

bool handleAddonManifestCatalog(int& i, int argc, char** argv,
                                  int& outRc) {
    if (std::strcmp(argv[i], "--gen-mod") == 0 && i + 1 < argc) {
        outRc = handleGenStandard(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mod-ui") == 0 && i + 1 < argc) {
        outRc = handleGenUI(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--gen-mod-util") == 0 &&
        i + 1 < argc) {
        outRc = handleGenUtility(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--info-wmod") == 0 && i + 1 < argc) {
        outRc = handleInfo(i, argc, argv); return true;
    }
    if (std::strcmp(argv[i], "--validate-wmod") == 0 && i + 1 < argc) {
        outRc = handleValidate(i, argc, argv); return true;
    }
    return false;
}

} // namespace cli
} // namespace editor
} // namespace wowee