#include "panels.h"
#include "data.h"

#include <imgui.h>
#include <imgui_internal.h>
#include <mutex>
#include <string>
#include <vector>

#include "core/icons_tabler.h"

namespace kanban {

static const char* k_columns[] = {"pendiente", "in-progress", "bloqueado", "completado"};
static const int   k_n_columns = sizeof(k_columns) / sizeof(k_columns[0]);

static ImU32 priority_color(const std::string& p) {
    if (p == "critica") return IM_COL32(255, 80, 80, 255);
    if (p == "alta")    return IM_COL32(255, 165, 0, 255);
    if (p == "media")   return IM_COL32(120, 170, 255, 255);
    if (p == "baja")    return IM_COL32(140, 140, 140, 255);
    return IM_COL32(180, 180, 180, 255);
}

static void draw_card(const Issue& iss) {
    ImGui::PushID(iss.id.c_str());

    ImVec2 size(0.0f, 64.0f);
    ImGui::BeginChild("card", size, true, ImGuiWindowFlags_NoScrollbar);

    // Header: id + priority badge
    ImGui::TextColored(ImColor(180, 180, 180, 255), "%s", iss.id.c_str());
    ImGui::SameLine();
    {
        ImVec2 cur = ImGui::GetCursorScreenPos();
        ImU32 c = priority_color(iss.priority);
        ImDrawList* dl = ImGui::GetWindowDrawList();
        float r = 5.0f;
        dl->AddCircleFilled(ImVec2(cur.x + r, cur.y + r + 2), r, c);
        ImGui::Dummy(ImVec2(2 * r + 4, 2 * r));
        ImGui::SameLine();
        ImGui::TextUnformatted(iss.priority.c_str());
    }

    // Title (truncate to ~60 chars)
    std::string t = iss.title;
    if (t.size() > 70) t = t.substr(0, 67) + "...";
    ImGui::TextWrapped("%s", t.c_str());

    // First domain chip
    if (!iss.domain.empty()) {
        ImGui::TextColored(ImColor(140, 200, 255, 255), TI_TAG " %s", iss.domain[0].c_str());
    }

    ImGui::EndChild();

    if (ImGui::IsItemClicked()) {
        refresh_issue_detail(iss.id);
    }

    // Drag source
    if (ImGui::BeginDragDropSource(ImGuiDragDropFlags_None)) {
        ImGui::SetDragDropPayload("KANBAN_ISSUE", iss.id.c_str(), iss.id.size() + 1);
        ImGui::Text("%s %s", iss.id.c_str(), t.c_str());
        ImGui::EndDragDropSource();
    }

    ImGui::PopID();
}

static void draw_column(const char* status_key, std::vector<const Issue*>& items) {
    ImGui::TableNextColumn();
    // Column header with count
    ImGui::PushFont(nullptr);
    ImGui::TextColored(ImColor(220, 220, 220, 255), "%s  (%zu)", status_key, items.size());
    ImGui::PopFont();
    ImGui::Separator();

    // Drop target on the whole column
    ImVec2 region = ImGui::GetContentRegionAvail();
    ImGui::BeginChild((std::string("col_") + status_key).c_str(), region, false);

    for (const auto* iss : items) {
        draw_card(*iss);
    }
    // Bottom drop zone
    ImGui::InvisibleButton("col_drop", ImVec2(-1, 16));
    if (ImGui::BeginDragDropTarget()) {
        if (const ImGuiPayload* p = ImGui::AcceptDragDropPayload("KANBAN_ISSUE")) {
            std::string id((const char*)p->Data, p->DataSize - 1);
            patch_issue_status(id, status_key);
        }
        ImGui::EndDragDropTarget();
    }
    ImGui::EndChild();

    if (ImGui::BeginDragDropTarget()) {
        if (const ImGuiPayload* p = ImGui::AcceptDragDropPayload("KANBAN_ISSUE")) {
            std::string id((const char*)p->Data, p->DataSize - 1);
            patch_issue_status(id, status_key);
        }
        ImGui::EndDragDropTarget();
    }
}

void draw_board() {
    if (!ImGui::Begin(TI_LAYOUT_KANBAN " Board")) {
        ImGui::End();
        return;
    }

    // Snapshot under lock
    std::vector<Issue> snapshot;
    {
        std::lock_guard<std::mutex> g(state().mu);
        snapshot = state().issues;
    }

    // Bucket issues by status
    std::vector<std::vector<const Issue*>> buckets(k_n_columns);
    int filtered_out = 0;
    for (const auto& iss : snapshot) {
        if (!passes_filters(iss)) {
            filtered_out++;
            continue;
        }
        for (int c = 0; c < k_n_columns; ++c) {
            if (iss.status == k_columns[c]) {
                buckets[c].push_back(&iss);
                break;
            }
        }
    }

    ImGui::Text("%zu total — %d filtered out", snapshot.size(), filtered_out);
    ImGui::Separator();

    if (ImGui::BeginTable("board_table", k_n_columns,
                         ImGuiTableFlags_BordersInnerV | ImGuiTableFlags_Resizable | ImGuiTableFlags_SizingStretchSame)) {
        ImGui::TableNextRow();
        for (int c = 0; c < k_n_columns; ++c) {
            draw_column(k_columns[c], buckets[c]);
        }
        ImGui::EndTable();
    }

    ImGui::End();
}

}  // namespace kanban