/*
 * installer.h
 * Shared header for the MontaukOS Installer
 * Copyright (c) 2026 Daniel Hammer
 */

#pragma once

#include <montauk/syscall.h>
#include <montauk/string.h>
#include <montauk/heap.h>
#include <gui/gui.hpp>
#include <gui/font.hpp>
#include <gui/mtk.hpp>

extern "C" {
#include <string.h>
#include <stdio.h>
}

using namespace gui;

// ============================================================================
// Constants
// ============================================================================

static constexpr int INIT_W       = 560;
static constexpr int INIT_H       = 500;
static constexpr int HEADER_H     = 44;
static constexpr int STEP_BAR_H   = 30;
static constexpr int CONTENT_TOP  = HEADER_H + STEP_BAR_H;
static constexpr int BOTTOM_H     = 48;
static constexpr int PAD          = 16;
static constexpr int BTN_H        = 30;
static constexpr int MAX_DISKS    = 32;
static constexpr int MAX_PARTS    = 32;

static constexpr int COMP_ROW_H      = 28;
static constexpr int COMP_INDENT     = 26;
static constexpr int COMP_TOGGLE_W   = 18;

// ============================================================================
// Install steps
// ============================================================================

enum InstallerMode {
    MODE_INSTALL = 0,
    MODE_UPDATE,
};

enum InstallStep {
    STEP_MODE_SELECT,
    STEP_SELECT_DISK,
    STEP_PARTITION_SCHEME,
    STEP_COMPONENTS,
    STEP_CONFIRM,
    STEP_INSTALLING,
    STEP_DONE,
    STEP_ERROR,
    // Update flow
    STEP_UPDATE_SELECT_PART,
    STEP_UPDATE_CONFIRM,
    STEP_UPDATING,
};

// ============================================================================
// Partition schemes
// ============================================================================

enum PartScheme {
    SCHEME_EFI_EXT2 = 0,
    SCHEME_SINGLE_FAT32,
    SCHEME_COUNT,
};

static const char* scheme_names[] = {
    "EFI + ext2 (recommended)",
    "Single FAT32 partition (entire disk)",
};

static const char* scheme_descs[] = {
    "EFI boot partition + ext2 root filesystem.",
    "One partition for boot, OS, and data. Simple and compatible.",
};

// ============================================================================
// Optional components
// ============================================================================

static constexpr int MAX_COMPONENT_PATHS = 16;

struct Component {
    const char* id;
    const char* label;
    const char* desc;      // shown in the status bar on hover
    int parent;            // index of parent component, or -1 for top level
    // Path that identifies this component in an image / on a target drive.
    const char* probe;
    // Files or directories (relative to the drive root, no "0:/" prefix)
    // owned by this component; nullptr-terminated. Empty for pure groups.
    const char* paths[MAX_COMPONENT_PATHS];
    // A child that needs its parent's base payload (e.g. gcc needs the
    // SDK sysroot). Checking it re-checks the parent.
    bool requires_parent;
    // Another component this one cannot work without (e.g. gcc drives the
    // binutils assembler/linker), or -1.
    int depends_on;

    // Runtime state
    bool checked;
    bool expanded;         // parents only
    bool present;          // this component (or a child) exists in the image
    bool base_present;     // own probe exists (parents with own payload)
    uint64_t bytes;        // exclusive payload size in the source image
};

extern Component g_components[];
extern const int g_component_count;

// components.cpp
void components_init();
void components_compute_sizes();
bool component_has_children(int idx);
mtk::CheckState component_state(int idx);
void component_toggle(int idx);
int  component_visible_rows(int* out, int max);
bool component_allows(const char* rel);
bool component_subtree_needed(const char* rel);
void components_set_from_target(int drive);
uint64_t components_selected_bytes();
uint64_t components_unselected_bytes();
void components_excluded_summary(char* buf, int bufsize);
bool components_sizes_ready();

// ============================================================================
// State
// ============================================================================

static constexpr int LOG_LINES    = 16;
static constexpr int LOG_LINE_LEN = 64;

struct InstallerState {
    int mode;  // InstallerMode

    // Install flow
    montauk::abi::DiskInfo disks[MAX_DISKS];
    int disk_count;
    int selected_disk;
    int partition_scheme;

    // Update flow
    montauk::abi::PartInfo parts[MAX_PARTS];
    int part_count;
    int selected_part;

    InstallStep step;
    char log[LOG_LINES][LOG_LINE_LEN];
    int  log_count;

    char status[96];
    uint64_t status_time;

    int mouse_x;
    int mouse_y;
    int comp_scroll;
};

// ============================================================================
// Global state (extern — defined in main.cpp)
// ============================================================================

extern int g_win_w, g_win_h;
extern InstallerState g_state;
extern Color g_accent;

// ============================================================================
// Shared layout helpers
// ============================================================================

inline int content_x() { return PAD; }
inline int content_w() { return g_win_w - PAD * 2; }
inline int content_bottom() { return g_win_h - BOTTOM_H; }

// Heading block: title line + smaller subtitle line
inline int heading_bottom() {
    return CONTENT_TOP + 14 + system_font_height() * 2 + 16;
}

inline Rect bottom_bar_rect() {
    return {0, g_win_h - BOTTOM_H, g_win_w, BOTTOM_H};
}

inline Rect primary_btn_rect() {
    int y = g_win_h - BOTTOM_H + (BOTTOM_H - BTN_H) / 2;
    return {g_win_w - PAD - 108, y, 108, BTN_H};
}

inline Rect secondary_btn_rect() {
    Rect p = primary_btn_rect();
    return {p.x - 8 - 96, p.y, 96, BTN_H};
}

inline Rect tertiary_btn_rect() {
    Rect s = secondary_btn_rect();
    return {s.x - 8 - 84, s.y, 84, BTN_H};
}

// Mode select cards
inline Rect mode_card_rect(int index) {
    int card_h = 56;
    int y = heading_bottom() + index * (card_h + 10);
    return {content_x(), y, content_w(), card_h};
}

// Disk / partition / scheme list rows
inline Rect list_row_rect(int index, int row_h) {
    int y = heading_bottom() + index * (row_h + 6);
    return {content_x(), y, content_w(), row_h};
}

static constexpr int DISK_ROW_H   = 48;
static constexpr int SCHEME_ROW_H = 50;
static constexpr int PART_ROW_H   = 48;

// Component tree viewport
inline Rect components_list_rect() {
    int top = heading_bottom();
    return {content_x(), top, content_w(), content_bottom() - top - 8};
}

inline Rect component_row_rect(int visible_index) {
    Rect list = components_list_rect();
    return {list.x, list.y + visible_index * COMP_ROW_H - g_state.comp_scroll,
            list.w, COMP_ROW_H};
}

// ============================================================================
// Function declarations — helpers (main.cpp)
// ============================================================================

void set_status(const char* msg);
void add_log(const char* msg);
void flush_ui();
void format_disk_size(char* buf, int bufsize, uint64_t sectors, uint16_t sectorSize);
void format_bytes(char* buf, int bufsize, uint64_t bytes);

// ============================================================================
// Function declarations — render.cpp
// ============================================================================

void render(uint32_t* pixels);

// ============================================================================
// Function declarations — actions.cpp
// ============================================================================

void installer_refresh_disks();
void installer_refresh_parts();
void do_install();
void do_update();
bool installer_path_exists(const char* abs_path);

// Heap-backed directory listing. Entries are full paths relative to the
// drive root (e.g. "apps/doom"), with is_dir derived from the trailing '/'
// the VFS appends to directory names. Survives nested listings, unlike the
// kernel's rotating readdir scratch pages.
struct DirEntry {
    char* rel;      // path relative to drive root, no trailing '/'
    bool is_dir;
};

struct DirList {
    DirEntry* entries;
    int count;
};

bool installer_list_dir(const char* abs_dir, DirList* out);
void installer_free_dir_list(DirList* list);