preset.lua

PRESET_FOLDER = EQE_PREFIX..'/db/presets'
PRESET_DEFAULT = 'CURRENT_BANDS'
function preset_file(name)
    return PRESET_FOLDER..'/'..name..'.lua'
end

local esc = require 'str_esc'

function eqe.save(name, input)
    input = input or eqe
    name = string.gsub(name or PRESET_DEFAULT, '%/', '\\')

    local path = preset_file(name)
    local buf = {}
    local function write(s)
        buf[#buf + 1] = s
    end
    write('return {')
    write('    {')
    write('        name = "preamp",')
    write('        gain = '..input.preamp..',')
    write('    },')
    for i=1,#input do
        local filter = input[i]
        write('    {')
        write('        name = "'..filter.name..'",')
        write('        frequency = '..filter.frequency..',')
        write('        Q = '..filter.Q..',')
        if filter.gain then
            write('        gain = '..filter.gain..',')
        end
        if filter.channel then
            write('        channel = '..filter.channel..',')
        end
        write('    },')
    end
    write('}')
    if not name and input == eqe and next(eqe.attr) then
        write(', ')
        write(esc(eqe.attr))
    end

    IPCD('WRITE_FILE('..esc(path)..','..esc(table.concat(buf))..')')
    IPCD('UPDATE_PRESET('..esc(name or PRESET_DEFAULT)..','..esc(path)..')')
end

local function loadLua(input)
    local f = load(input)
    if not f then return end

    local _ = _ENV
    _ENV = {}
    local t, attr = f()
    _ENV = _

    local x = {}

    -- cant inline this because i set _ENV to {} above
    for k,v in pairs(t) do
        if v.name == 'preamp' then
            eqe.preamp = v.gain
        else
            if v.name == 'eq' then v.name = 'peak' end
            x[#x + 1] = v
        end
    end
    if attr then
        for k,v in pairs(attr) do
            eqe.attr[k] = v
        end
    end

    return x
end

local function loadApo(input)
    local x = nil
    for s in input:gmatch('(.-)\n') do
        local f = '(%-?%d+%.?%d*)'
        local preamp = s:match('Preamp%: '..f..' dB')
        if preamp then
            x = x or {}
            eqe.preamp = assert(tonumber(preamp))
        elseif s == '' then
            -- pass
        else
            local supportedKinds = {
                PK = 'peak',
                LSC = 'lowshelf',
                HSC = 'highshelf',
            }
            local kind, fc, gain, q =
                s:match('Filter %d+%: ON (.+) Fc '..f..' Hz Gain '..f..' dB Q '..f)
            if not kind or not fc or not gain or not q then return end
            x = x or {}
            x[#x + 1] = {
                name = assert(supportedKinds[kind]),
                gain = assert(tonumber(gain)),
                Q = assert(tonumber(q)),
                frequency = assert(tonumber(fc)),
            }
        end
    end
    return x
end

function eqe.loadstring(input, dontSave)
    local x = assert(loadLua(input) or loadApo(input))
    eqe.insert(nil, x, true)
    eqe.update()
    if not dontSave then
        eqe.save()
    end
end

function eqe.load(name)
    local f = io.open(preset_file(name or PRESET_DEFAULT), 'r')
    local input = f:read('*a')
    f:close()
    eqe.loadstring(input, not name)
end