import gg
import sokol.sapp
import sokol.sgl
import x.ttf
import x.ttf.render_sokol
import os

const custom_font_path = os.args[1] or {
    os.resource_abs_path(os.join_path('..', 'assets', 'fonts', 'Imprima-Regular.ttf'))
}
const custom_txt_path = os.args[2] or { os.resource_abs_path('draw_static_text.txt') }

const custom_text_start_y = 80

const win_width = 400
const win_height = 400
const bg_color = gg.Color{50, 255, 50, 255}

const block_txt = os.read_file(custom_txt_path) or { '' }
const font_paths = [
    os.resource_abs_path(os.join_path('..', 'assets', 'fonts', 'RobotoMono-Regular.ttf')),
    custom_font_path,
]

// UI
struct App_data {
pub mut:
    gg              &gg.Context = unsafe { nil }
    init_flag       bool
    tf              []ttf.TTF_File
    ttf_render      []render_sokol.TTF_render_Sokol
    text_ready_flag bool
}

fn my_init(mut app App_data) {
    app.init_flag = true
    texts := ['Hello, font: ${os.file_name(custom_font_path)}', block_txt]!
    dump(texts[0])
    for i in 0 .. 2 {
        mut txt := unsafe { &app.ttf_render[i] }
        txt.destroy_texture()
        txt.create_text_block(texts[i], 1024, 1024, 24)
        txt.create_texture()
    }
}

fn draw_frame(mut app App_data) {
    app.gg.begin()
    sgl.defaults()
    sgl.matrix_mode_projection()
    sgl.ortho(0.0, f32(sapp.width()), f32(sapp.height()), 0.0, -1.0, 1.0)
    sgl.c4b(0, 0, 0, 255) // black
    // draw text only if the app is already initialized
    if app.init_flag != true {
        app.gg.end()
    }

    // draw hello
    mut txt1 := unsafe { &app.ttf_render[0] }
    txt1.draw_text_bmp(app.gg, 5, 5)

    // draw the custom text
    txt2 := unsafe { &app.ttf_render[1] }
    txt2.draw_text_bmp(app.gg, 30, custom_text_start_y)
    app.gg.end()
}

fn main() {
    println('Use `v run draw_static_text.v [FONT_PATH] [TEXT_FILE_PATH]`')
    println('> Current command: os.args[0] ${custom_font_path} ${custom_txt_path}')
    mut app := &App_data{}
    app.gg = gg.new_context(
        width:        win_width
        height:       win_height
        window_title: 'Draw custom text, with custom font'
        user_data:    app
        bg_color:     bg_color
        frame_fn:     draw_frame
        init_fn:      my_init
    )

    // load the TTF fonts:
    for font_path in font_paths {
        mut tf := ttf.TTF_File{}
        tf.buf = os.read_bytes(font_path) or { panic(err) }
        println('Read TrueTypeFont file [${font_path}], len: ${tf.buf.len}')
        tf.init()
        println('Unit per EM: ${tf.units_per_em}')
        app.tf << tf
    }

    // TTF hello render
    app.ttf_render << &render_sokol.TTF_render_Sokol{
        bmp: &ttf.BitMap{
            tf:       &app.tf[0]
            buf:      unsafe { malloc_noscan(32000000) }
            buf_size: (32000000)
            color:    0xFF0000FF
        }
    }

    // TTF custom text render
    app.ttf_render << &render_sokol.TTF_render_Sokol{
        bmp: &ttf.BitMap{
            tf:       &app.tf[1]
            buf:      unsafe { malloc_noscan(32000000) }
            buf_size: (32000000)
            color:    0x2020EEFF
        }
    }

    // setup sokol_gfx
    app.gg.run()
}