/*
 * Copyright 2018, Jérôme Duval, jerome.duval@gmail.com.
 * Copyright 2005-2009, Axel Dörfler, axeld@pinc-software.de.
 * Distributed under the terms of the MIT License.
 */


#include <frame_buffer_console.h>

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>

#include <KernelExport.h>
#include <kernel.h>
#include <lock.h>
#include <boot_item.h>
#include <vm/vm.h>
#include <fs/devfs.h>
#include <boot/kernel_args.h>

#ifndef _BOOT_MODE
#include <vesa_info.h>

#include <edid.h>
#else
#define mutex_lock(...)
#define mutex_unlock(...)
#undef arch_cpu_enable_user_access
#undef arch_cpu_disable_user_access
#define arch_cpu_enable_user_access()
#define arch_cpu_disable_user_access()
#endif

#include "font.h"


//#define TRACE_FB_CONSOLE
#ifdef TRACE_FB_CONSOLE
#       define TRACE(x) dprintf x
#else
#       define TRACE(x) ;
#endif


struct console_info {
        mutex   lock;
        area_id area;

        addr_t  frame_buffer;
        int32   width;
        int32   height;
        int32   depth;
        int32   bytes_per_pixel;
        int32   bytes_per_row;

        int32   columns;
        int32   rows;
        int32   cursor_x;
        int32   cursor_y;
        FramebufferFont* font;
};

// Palette is (white and black are exchanged):
//      0 - white, 1 - blue, 2 - green, 3 - cyan, 4 - red, 5 - magenta, 6 - yellow,
//  7 - black
//  8-15 - same but bright (we're ignoring those)

static uint8 sPalette8[] = {
        63, 32, 52, 70, 42, 88, 67, 0,
};
static uint16 sPalette15[] = {
        // 0bbbbbgggggrrrrr (5-5-5)
        0x7fff, 0x1993, 0x2660, 0x0273, 0x6400, 0x390f, 0x6ea0, 0x0000,
};
static uint16 sPalette16[] = {
        // bbbbbggggggrrrrr (5-6-5)
        0xffff, 0x3333, 0x4cc0, 0x04d3, 0xc800, 0x722f, 0xdd40, 0x0000,
};
static uint32 sPalette32[] = {
        // is also used by 24 bit modes
        0xffffff,       // white
        0x336698,       // blue
        0x4e9a00,       // green
        0x06989a,       // cyan
        0xcc0000,       // red
        0x73447b,       // magenta
        0xdaa800,       // yellow
        0x000000,       // black
};

static struct console_info sConsole;

#ifndef _BOOT_MODE
static struct frame_buffer_boot_info sBootInfo;
static struct vesa_mode* sVesaModes;
#endif


static inline uint8
foreground_color(uint8 attr)
{
        return attr & 0x7;
}


static inline uint8
background_color(uint8 attr)
{
        return (attr >> 4) & 0x7;
}


static uint8*
get_palette_entry(uint8 index)
{
        switch (sConsole.depth) {
                case 8:
                        return &sPalette8[index];
                case 15:
                        return (uint8*)&sPalette15[index];
                case 16:
                        return (uint8*)&sPalette16[index];
                default:
                        return (uint8*)&sPalette32[index];
        }
}


static uint16
get_font_data(uint8 glyph, int y)
{
        if (sConsole.font->glyphWidth > 8) {
                uint16* data = (uint16*)sConsole.font->data;
                return data[sConsole.font->glyphHeight * glyph + y];
        } else
                return sConsole.font->data[sConsole.font->glyphHeight * glyph + y];
}


static void
render_glyph(int32 column, int32 row, uint8 glyph, uint8 attr)
{
        // we're ASCII only
        if (glyph > 127)
                glyph = 127;

        if (sConsole.depth >= 8) {
                uint8* base = (uint8*)(sConsole.frame_buffer
                        + sConsole.bytes_per_row * row * sConsole.font->glyphHeight
                        + column * sConsole.font->glyphWidth * sConsole.bytes_per_pixel);
                uint8* color = get_palette_entry(foreground_color(attr));
                uint8* backgroundColor = get_palette_entry(background_color(attr));

                arch_cpu_enable_user_access();
                for (int y = 0; y < sConsole.font->glyphHeight; y++) {
                        uint16_t bits = get_font_data(glyph, y);
                        for (int x = 0; x < sConsole.font->glyphWidth; x++) {
                                for (int32 i = 0; i < sConsole.bytes_per_pixel; i++) {
                                        if (bits & 1)
                                                base[x * sConsole.bytes_per_pixel + i] = color[i];
                                        else {
                                                base[x * sConsole.bytes_per_pixel + i]
                                                        = backgroundColor[i];
                                        }
                                }
                                bits >>= 1;
                        }

                        base += sConsole.bytes_per_row;
                }
                arch_cpu_disable_user_access();
        } else {
                // VGA mode will be treated as monochrome
                // (ie. only the first plane will be used)

                uint8* base = (uint8*)(sConsole.frame_buffer
                        + sConsole.bytes_per_row * row * sConsole.font->glyphHeight
                        + column * sConsole.font->glyphWidth / 8);
                uint8 baseOffset =  (column * sConsole.font->glyphWidth) & 0x7;

                arch_cpu_enable_user_access();
                for (int y = 0; y < sConsole.font->glyphHeight; y++) {
                        uint16_t bits = get_font_data(glyph, y);
                        uint8 offset = baseOffset;
                        uint8 mask = 1 << (7 - baseOffset);

                        for (int x = 0; x < sConsole.font->glyphWidth; x++) {
                                if (mask == 0)
                                        mask = 128;

                                // black on white
                                if (bits & 1)
                                        base[offset / 8] &= ~mask;
                                else
                                        base[offset / 8] |= mask;

                                bits >>= 1;
                                mask >>= 1;
                                offset += 1;
                        }

                        base += sConsole.bytes_per_row;
                }
                arch_cpu_disable_user_access();
        }
}


static void
draw_cursor(int32 x, int32 y)
{
        if (x < 0 || y < 0)
                return;

        x *= sConsole.font->glyphWidth * sConsole.bytes_per_pixel;
        y *= sConsole.font->glyphHeight;
        int32 endX = x + sConsole.font->glyphWidth * sConsole.bytes_per_pixel;
        int32 endY = y + sConsole.font->glyphHeight;
        uint8* base = (uint8*)(sConsole.frame_buffer + y * sConsole.bytes_per_row);

        if (sConsole.depth < 8) {
                x /= 8;
                endY /= 8;
        }

        arch_cpu_enable_user_access();
        for (; y < endY; y++) {
                for (int32 x2 = x; x2 < endX; x2++)
                        base[x2] = ~base[x2];

                base += sConsole.bytes_per_row;
        }
        arch_cpu_disable_user_access();
}


static status_t
console_get_size(int32* _width, int32* _height)
{
        *_width = sConsole.columns;
        *_height = sConsole.rows;

        return B_OK;
}


static void
console_move_cursor(int32 x, int32 y)
{
        if (!frame_buffer_console_available())
                return;

        draw_cursor(sConsole.cursor_x, sConsole.cursor_y);
        draw_cursor(x, y);

        sConsole.cursor_x = x;
        sConsole.cursor_y = y;
}


static void
console_put_glyph(int32 x, int32 y, uint8 glyph, uint8 attr)
{
        if (x >= sConsole.columns || y >= sConsole.rows
                || !frame_buffer_console_available())
                return;

        render_glyph(x, y, glyph, attr);
}


static void
console_fill_glyph(int32 x, int32 y, int32 width, int32 height, uint8 glyph,
        uint8 attr)
{
        if (x >= sConsole.columns || y >= sConsole.rows
                || !frame_buffer_console_available())
                return;

        int32 left = x + width;
        if (left > sConsole.columns)
                left = sConsole.columns;

        int32 bottom = y + height;
        if (bottom > sConsole.rows)
                bottom = sConsole.rows;

        for (; y < bottom; y++) {
                for (int32 x2 = x; x2 < left; x2++) {
                        render_glyph(x2, y, glyph, attr);
                }
        }
}


static void
console_blit(int32 srcx, int32 srcy, int32 width, int32 height, int32 destx,
        int32 desty)
{
        if (!frame_buffer_console_available())
                return;

        height *= sConsole.font->glyphHeight;
        srcy *= sConsole.font->glyphHeight;
        desty *= sConsole.font->glyphHeight;

        if (sConsole.depth >= 8) {
                width *= sConsole.font->glyphWidth * sConsole.bytes_per_pixel;
                srcx *= sConsole.font->glyphWidth * sConsole.bytes_per_pixel;
                destx *= sConsole.font->glyphWidth * sConsole.bytes_per_pixel;
        } else {
                // monochrome mode
                width = width * sConsole.font->glyphWidth / 8;
                srcx = srcx * sConsole.font->glyphWidth / 8;
                destx = destx * sConsole.font->glyphWidth / 8;
        }

        arch_cpu_enable_user_access();
        for (int32 y = 0; y < height; y++) {
                memmove((void*)(sConsole.frame_buffer + (desty + y)
                                * sConsole.bytes_per_row + destx),
                        (void*)(sConsole.frame_buffer + (srcy + y) * sConsole.bytes_per_row
                                + srcx), width);
        }
        arch_cpu_disable_user_access();
}


static void
console_clear(uint8 attr)
{
        if (!frame_buffer_console_available())
                return;

        arch_cpu_enable_user_access();
        switch (sConsole.bytes_per_pixel) {
                case 1:
                        if (sConsole.depth >= 8) {
                                memset((void*)sConsole.frame_buffer,
                                        sPalette8[background_color(attr)],
                                        sConsole.height * sConsole.bytes_per_row);
                        } else {
                                // special case for VGA mode
                                memset((void*)sConsole.frame_buffer, 0xff,
                                        sConsole.height * sConsole.bytes_per_row);
                        }
                        break;
                default:
                {
                        uint8* base = (uint8*)sConsole.frame_buffer;
                        uint8* color = get_palette_entry(background_color(attr));

                        for (int32 y = 0; y < sConsole.height; y++) {
                                for (int32 x = 0; x < sConsole.width; x++) {
                                        for (int32 i = 0; i < sConsole.bytes_per_pixel; i++) {
                                                base[x * sConsole.bytes_per_pixel + i] = color[i];
                                        }
                                }
                                base += sConsole.bytes_per_row;
                        }
                        break;
                }
        }
        arch_cpu_disable_user_access();

        sConsole.cursor_x = -1;
        sConsole.cursor_y = -1;
}


static status_t
console_std_ops(int32 op, ...)
{
        switch (op) {
                case B_MODULE_INIT:
                        return frame_buffer_console_available() ? B_OK : B_ERROR;
                case B_MODULE_UNINIT:
                        return B_OK;

                default:
                        return B_ERROR;
        }
}


console_module_info gFrameBufferConsoleModule = {
        {
                FRAME_BUFFER_CONSOLE_MODULE_NAME,
                0,
                console_std_ops
        },
        &console_get_size,
        &console_move_cursor,
        &console_put_glyph,
        &console_fill_glyph,
        &console_blit,
        &console_clear,
};


//      #pragma mark -


bool
frame_buffer_console_available(void)
{
        return sConsole.frame_buffer != 0;
}


status_t
frame_buffer_update(addr_t baseAddress, int32 width, int32 height, int32 depth,
        int32 bytesPerRow)
{
        TRACE(("frame_buffer_update(buffer = %p, width = %ld, height = %ld, "
                "depth = %ld, bytesPerRow = %ld)\n", (void*)baseAddress, width, height,
                depth, bytesPerRow));

        mutex_lock(&sConsole.lock);

        if (width <= 1920 || height <= 1080) {
                sConsole.font = &smallFont;
        } else {
                sConsole.font = &bigFont;
        }

        sConsole.frame_buffer = baseAddress;
        sConsole.width = width;
        sConsole.height = height;
        sConsole.depth = depth;
        sConsole.bytes_per_pixel = (depth + 7) / 8;
        sConsole.bytes_per_row = bytesPerRow;
        sConsole.columns = sConsole.width / sConsole.font->glyphWidth;
        sConsole.rows = sConsole.height / sConsole.font->glyphHeight;
        // initially, the cursor is hidden
        sConsole.cursor_x = -1;
        sConsole.cursor_y = -1;

        TRACE(("framebuffer mapped at %p, %ld columns, %ld rows\n",
                (void*)sConsole.frame_buffer, sConsole.columns, sConsole.rows));

        mutex_unlock(&sConsole.lock);
        return B_OK;
}


#ifndef _BOOT_MODE
status_t
frame_buffer_console_init(kernel_args* args)
{
        mutex_init(&sConsole.lock, "console_lock");

        if (!args->frame_buffer.enabled)
                return B_OK;

#if KERNEL_PMAP_BASE
        const addr_t frameBuffer = (KERNEL_PMAP_BASE
                + args->frame_buffer.physical_buffer.start);
        frame_buffer_update((addr_t)frameBuffer, args->frame_buffer.width,
                args->frame_buffer.height, args->frame_buffer.depth,
                args->frame_buffer.bytes_per_row);
        return B_OK;
#else
        return B_NO_INIT;
#endif
}


status_t
frame_buffer_console_init_post_vm(kernel_args* args)
{
        if (!args->frame_buffer.enabled)
                return B_OK;

        void* frameBuffer;
        sConsole.area = map_physical_memory("frame buffer",
                args->frame_buffer.physical_buffer.start,
                args->frame_buffer.physical_buffer.size, B_ANY_KERNEL_ADDRESS,
                B_KERNEL_READ_AREA | B_KERNEL_WRITE_AREA | B_CLONEABLE_AREA,
                &frameBuffer);
        if (sConsole.area < 0)
                return sConsole.area;

        frame_buffer_update((addr_t)frameBuffer, args->frame_buffer.width,
                args->frame_buffer.height, args->frame_buffer.depth,
                args->frame_buffer.bytes_per_row);

        sBootInfo.area = sConsole.area;
        sBootInfo.physical_frame_buffer = args->frame_buffer.physical_buffer.start;
        sBootInfo.frame_buffer = (addr_t)frameBuffer;
        sBootInfo.width = args->frame_buffer.width;
        sBootInfo.height = args->frame_buffer.height;
        sBootInfo.depth = args->frame_buffer.depth;
        sBootInfo.bytes_per_row = args->frame_buffer.bytes_per_row;
        sBootInfo.vesa_capabilities = args->vesa_capabilities;

        add_boot_item(FRAME_BUFFER_BOOT_INFO, &sBootInfo,
                sizeof(frame_buffer_boot_info));

        sVesaModes = (vesa_mode*)malloc(args->vesa_modes_size);
        if (sVesaModes != NULL && args->vesa_modes_size > 0) {
                memcpy(sVesaModes, args->vesa_modes, args->vesa_modes_size);
                add_boot_item(VESA_MODES_BOOT_INFO, sVesaModes, args->vesa_modes_size);
        }

        if (args->edid_info != NULL) {
                edid1_info* info = (edid1_info*)malloc(sizeof(edid1_info));
                if (info != NULL) {
                        memcpy(info, args->edid_info, sizeof(edid1_info));
                        add_boot_item(VESA_EDID_BOOT_INFO, info, sizeof(edid1_info));
                }
        }

        return B_OK;
}


status_t
frame_buffer_console_init_post_modules(kernel_args* args)
{
        if (sConsole.frame_buffer == 0)
                return B_OK;

        // try to set frame buffer memory to write combined

        return vm_set_area_memory_type(sConsole.area,
                args->frame_buffer.physical_buffer.start, B_WRITE_COMBINING_MEMORY);
}


//      #pragma mark -


status_t
_user_frame_buffer_update(addr_t baseAddress, int32 width, int32 height,
        int32 depth, int32 bytesPerRow)
{
        debug_stop_screen_debug_output();

        if (geteuid() != 0)
                return B_NOT_ALLOWED;
        if (IS_USER_ADDRESS(baseAddress) && baseAddress != 0)
                return B_BAD_ADDRESS;

        return frame_buffer_update(baseAddress, width, height, depth, bytesPerRow);
}
#endif