#506 two-file bundled offline installer generation

build/_offline.lua

@@ -0,0 +1,114 @@
+---@diagnostic disable: undefined-global
+
+local b64_lookup = {
+    ['A'] = 0,  ['B'] = 1,  ['C'] = 2,  ['D'] = 3,  ['E'] = 4,  ['F'] = 5,  ['G'] = 6,  ['H'] = 7,  ['I'] = 8,  ['J'] = 9,  ['K'] = 10, ['L'] = 11, ['M'] = 12, ['N'] = 13, ['O'] = 14, ['P'] = 15, ['Q'] = 16, ['R'] = 17, ['S'] = 18, ['T'] = 19, ['U'] = 20, ['V'] = 21, ['W'] = 22, ['X'] = 23, ['Y'] = 24, ['Z'] = 25,
+    ['a'] = 26, ['b'] = 27, ['c'] = 28, ['d'] = 29, ['e'] = 30, ['f'] = 31, ['g'] = 32, ['h'] = 33, ['i'] = 34, ['j'] = 35, ['k'] = 36, ['l'] = 37, ['m'] = 38, ['n'] = 39, ['o'] = 40, ['p'] = 41, ['q'] = 42, ['r'] = 43, ['s'] = 44, ['t'] = 45, ['u'] = 46, ['v'] = 47, ['w'] = 48, ['x'] = 49, ['y'] = 50, ['z'] = 51,
+    ['0'] = 52, ['1'] = 53, ['2'] = 54, ['3'] = 55, ['4'] = 56, ['5'] = 57, ['6'] = 58, ['7'] = 59, ['8'] = 60, ['9'] = 61, ['+'] = 62, ['/'] = 63
+}
+
+local BYTE  = 0xFF
+local CHAR  = string.char
+local BOR   = bit.bor           ---@type function
+local BAND  = bit.band          ---@type function
+local LSHFT = bit.blshift       ---@type function
+local RSHFT = bit.blogic_rshift ---@type function
+
+-- decode a base64 string
+---@param input string
+local function b64_decode(input)
+---@diagnostic disable-next-line: undefined-field
+    local t_start = os.epoch("local")
+
+    local decoded = {}
+
+    local c_idx, idx = 1, 1
+
+    for _ = 1, input:len() / 4 do
+        local block = input:sub(idx, idx + 4)
+        local word = 0x0
+
+        -- build the 24-bit sequence from the 4 characters
+        for i = 1, 4 do
+            local num = b64_lookup[block:sub(i, i)]
+
+            if num then
+                word = BOR(word, LSHFT(b64_lookup[block:sub(i, i)], (4 - i) * 6))
+            end
+        end
+
+        -- decode the 24-bit sequence as 8 bytes
+        for i = 1, 3 do
+            local char = BAND(BYTE, RSHFT(word, (3 - i) * 8))
+
+            if char ~= 0 then
+                decoded[c_idx] = CHAR(char)
+                c_idx = c_idx + 1
+            end
+        end
+
+        idx = idx + 4
+    end
+
+---@diagnostic disable-next-line: undefined-field
+    local elapsed = (os.epoch("local") - t_start)
+    local decoded_str = table.concat(decoded)
+
+    return decoded_str, elapsed
+end
+
+-- write files recursively from base64 encodings in a table
+---@param files table
+---@param path string
+local function write_files(files, path)
+    fs.makeDir(path)
+
+    for k, v in pairs(files) do
+        if type(v) == "table" then
+            if k == "system" then
+                -- write system files to root
+                write_files(v, "/")
+            else
+                -- descend into directories
+                write_files(v, path .. "/" .. k .. "/")
+            end
+
+---@diagnostic disable-next-line: undefined-field
+            os.sleep(0.05)
+        else
+            local handle = fs.open(path .. k, "w")
+            local text, time = b64_decode(v)
+
+            print("decoded '" .. k .. "' in " .. time .. "ms")
+
+            handle.write(text)
+            handle.close()
+        end
+    end
+end
+
+local function write_install()
+    local handle = fs.open("install_manifest.json", "w")
+    handle.write(b64_decode(install_manifest))
+    handle.close()
+
+    handle = fs.open("ccmsim.lua", "w")
+    handle.write(b64_decode(ccmsi_offline))
+    handle.close()
+end
+
+lgray()
+
+-- write both app and dependency files
+write_files(app_files, "/")
+write_files(dep_files, "/")
+
+-- write a install manifest and offline installer
+write_install()
+
+green()
+print("Done!")
+white()
+print("Use can use the freshly installed 'ccmsim' program to manage your off-line installation.")
+lgray()
+print("You do not need to run it now though, your system is all ready to start! Launch with 'startup'.")
+white()