--- a/autoload/unreal.vim	Fri Sep 25 09:44:49 2020 -0700
+++ b/autoload/unreal.vim	Fri Jan 22 16:38:18 2021 -0800
@@ -2,6 +2,8 @@
 
 " Utilities {{{
 
+let s:basedir = expand('<sfile>:p:h:h')
+
 function! unreal#throw(message)
     throw "unreal: ".a:message
 endfunction
@@ -55,27 +57,57 @@
 
 " }}}
 
-" Project Management {{{
+" {{{ Scripts and Cache Files
+
+let s:scriptsdir = s:basedir.'\scripts'
+
+function! unreal#get_vim_script_path(scriptname) abort
+    return s:scriptsdir.s:dirsep.a:scriptname.s:scriptext
+endfunction
 
-function! unreal#find_project_dir() abort
-    if !empty(g:unreal_project_dir_finder)
-        return call(g:unreal_project_dir_finder)
+function! unreal#get_cache_path(name, ...) abort
+    if empty(g:unreal_branch_dir)
+        call unreal#throw("No UE branch defined")
+    endif
+    let l:cache_dir = g:unreal_branch_dir.s:dirsep.".vimunreal"
+    let l:path = l:cache_dir.s:dirsep.a:name
+    if a:0 && a:1 && !isdirectory(l:cache_dir)
+        call mkdir(l:cache_dir)
+    endif
+    return l:path
+endfunction
+
+" }}}
+
+" Branch and Project Management {{{
+
+function! unreal#find_branch_dir_and_project() abort
+    call unreal#find_branch_dir()
+
+    if !empty(g:unreal_branch_dir)
+        call unreal#find_project()
+    endif
+endfunction
+
+function! unreal#find_branch_dir() abort
+    if !empty(g:unreal_branch_dir_finder)
+        let l:branch_dir = call(g:unreal_branch_dir_finder)
+    else
+        let l:branch_dir = unreal#default_branch_dir_finder(getcwd())
     endif
 
-    let l:path = getcwd()
-    try
-        let l:proj_dir = unreal#default_project_dir_finder(l:path)
-    catch /^unreal:/
-        let l:proj_dir = ''
-    endtry
-    call unreal#set_project_dir(l:proj_dir)
+    if !empty(l:branch_dir)
+        call unreal#set_branch_dir(l:branch_dir, 1)  " Set branch silently.
+    else
+        call unreal#throw("No UE branch found!")
+    endif
 endfunction
 
-function! unreal#default_project_dir_finder(path) abort
+function! unreal#default_branch_dir_finder(path) abort
     let l:cur = a:path
     let l:prev = ""
     while l:cur != l:prev
-        let l:markers = globpath(l:cur, g:unreal_project_dir_marker, 0, 1)
+        let l:markers = globpath(l:cur, g:unreal_branch_dir_marker, 0, 1)
         if !empty(l:markers)
             call unreal#trace("Found marker file: ".l:markers[0])
             return l:cur
@@ -83,18 +115,30 @@
         let l:prev = l:cur
         let l:cur = fnamemodify(l:cur, ':h')
     endwhile
-    call unreal#throw("No UE project markers found.")
+    return ""
 endfunction
 
-function! unreal#set_project_dir(project_dir, ...) abort
+function! unreal#set_branch_dir(branch_dir, ...) abort
     " Strip any end slashes on the directory path.
-    let g:unreal_project_dir = fnamemodify(a:project_dir, ':s?[/\\]$??')
+    let l:prev_dir = g:unreal_branch_dir
+    let g:unreal_branch_dir = fnamemodify(a:branch_dir, ':s?[/\\]$??')
+    let l:branch_was_set = !empty(g:unreal_branch_dir)
+
+    " Update our projects infos.
+    let g:unreal_branch_projects = unreal#get_branch_projects(g:unreal_branch_dir)
 
-    let l:proj_was_set = !empty(g:unreal_project_dir)
+    " Notify our modules.
+    if l:branch_was_set
+        call unreal#call_modules('on_branch_changed', g:unreal_branch_dir)
+    else
+        call unreal#call_modules('on_branch_cleared')
+    endif
 
+    " Auto-set the Vimcrosoft solution if that plugin is installed.
+    " TODO: move this into a module.
     if exists(":VimcrosoftSetSln")
-        if l:proj_was_set
-            let l:sln_files = glob(g:unreal_project_dir.s:dirsep."*.sln", 0, 1)
+        if l:branch_was_set
+            let l:sln_files = glob(g:unreal_branch_dir.s:dirsep."*.sln", 0, 1)
             if !empty(l:sln_files)
                 " Vimcrosoft might have auto-found the same solution, already, 
                 " in which case we don't have to set it.
@@ -109,20 +153,121 @@
         endif
     endif
 
-    if l:proj_was_set
-        call unreal#call_modules('on_project_changed', g:unreal_project_dir)
-    else
-        call unreal#call_modules('on_project_cleared')
+    let l:silent = a:0 && a:1
+    if !l:silent
+        if l:branch_was_set
+            echom "UE branch set to: ".g:unreal_branch_dir
+        else
+            echom "UE branch cleared"
+        endif
+    endif
+endfunction
+
+function! unreal#find_project() abort
+    if empty(g:unreal_branch_dir)
+        call unreal#throw("No UE branch set!")
+    endif
+
+    if len(g:unreal_branch_projects) == 0
+        call unreal#throw("No UE projects found in branch: ".g:unreal_branch_dir)
+    endif
+
+    let l:proj = ""
+    let l:cached_proj_file = unreal#get_cache_path("LastProject.txt")
+    try
+        let l:cached_proj = readfile(l:cached_proj_file, '', 1)
+    catch
+        let l:cached_proj = []
+    endtry
+    if len(l:cached_proj) > 0 && !empty(l:cached_proj[0])
+        if has_key(g:unreal_branch_projects, l:cached_proj[0])
+            let l:proj = l:cached_proj[0]
+            call unreal#trace("Found previously set project: ".l:proj)
+        endif
+    endif
+
+    if l:proj == ""
+        let l:projnames = sort(keys(g:unreal_branch_projects))
+        if len(l:projnames) > 0
+            let l:proj = l:projnames[0]
+            call unreal#trace("Picking first project in branch: ".l:proj)
+        endif
     endif
 
-    let l:silent = a:0 && a:1
-    if !l:silent
-        if l:proj_was_set
-            echom "UE Project set to: ".g:unreal_project_dir
+    if l:proj == ""
+        call unreal#throw("No UE projects found in branch: ".g:unreal_branch_dir)
+    else
+        call unreal#set_project(l:proj)
+    endif
+endfunction
+
+function! unreal#set_project(projname) abort
+    let g:unreal_project = a:projname
+
+    let l:cached_proj_file = unreal#get_cache_path("LastProject.txt", 1) " Auto-create cache dir.
+    call writefile([a:projname], l:cached_proj_file)
+
+    call unreal#trace("Set UE project: ".a:projname)
+endfunction
+
+function! unreal#get_branch_projects(branch_dir)
+    if empty(a:branch_dir)
+        return {}
+    endif
+
+    " Reset the known projects.
+    let l:projs = {}
+    call unreal#trace("Finding projects in branch: ".a:branch_dir)
+    
+    " Find project files in the branch directory.
+    let l:dirs = readdir(a:branch_dir)
+    for l:dir in l:dirs
+        let l:dirpath = a:branch_dir.s:dirsep.l:dir.s:dirsep
+        let l:uprojfiles = glob(l:dirpath."*.uproject", 0, 1)
+        if len(l:uprojfiles) > 0
+            let l:lines = readfile(l:uprojfiles[0])
+            let l:jsonraw = join(l:lines, "\n")
+            let l:json = json_decode(l:jsonraw)
+            let l:json["Path"] = l:uprojfiles[0]
+            let l:projname = fnamemodify(l:uprojfiles[0], ':t:r')
+            let l:projs[l:projname] = l:json
+            call unreal#trace("Found project: ".l:projname)
+        endif
+    endfor
+
+    return l:projs
+endfunction
+
+function! unreal#get_project_info(proppath) abort
+    if empty(g:unreal_project) || empty(g:unreal_branch_projects)
+        call unreal#throw("No project(s) set!")
+    endif
+
+    let l:proj = g:unreal_branch_projects[g:unreal_project]
+
+    let l:cur = l:proj
+    let l:propnames = split(a:proppath, '.')
+    for l:propname in l:propnames
+        if type(l:cur) == type([])
+            let l:cur = l:cur[str2nr(l:propname)]
         else
-            echom "UE Project cleared"
+            let l:cur = l:cur[l:propname]
         endif
+    endfor
+endfunction
+
+function! unreal#find_project_module_of_type(project, module_type) abort
+    if empty(a:project) || empty(g:unreal_branch_projects)
+        call unreal#throw("No project(s) set!")
     endif
+
+    let l:proj = g:unreal_branch_projects[a:project]
+    for l:module in l:proj["Modules"]
+        if get(l:module, "Type", "") == a:module_type
+            return copy(l:module)
+        endif
+    endfor
+    return {}
 endfunction
 
 let s:extra_args_version = 1
@@ -160,10 +305,46 @@
 
 " }}}
 
-" Commands {{{
+" Configuration and Platform {{{
+
+let s:unreal_configs = []
+
+function! s:cache_unreal_configs() abort
+    if len(s:unreal_configs) == 0
+        for l:state in g:unreal_config_states
+            for l:target in g:unreal_config_targets
+                call add(s:unreal_configs, l:state.l:target)
+            endfor
+        endfor
+    endif
+endfunction
+
+function! s:parse_config_state_and_target(config) abort
+    let l:alen = len(a:config)
 
-function! unreal#generate_project_files() abort
-    call unreal#run_make("ugenprojfiles")
+    let l:config_target = ""
+    for l:target in g:unreal_config_targets
+        let l:tlen = len(l:target)
+        if l:alen > l:tlen && a:config[l:alen - l:tlen : ] == l:target
+            let l:config_target = l:target
+            break
+        endif
+    endfor
+
+    let l:config_state = a:config[0 : l:alen - t:tlen - 1]
+    
+    if index(g:unreal_config_states, l:config_state) >= 0 ||
+                \index(g:unreal_config_targets, l:config_target) >= 0
+        return [l:config_state, l:config_target]
+    else
+        call unreal#throw("Invalid config state or target: ".l:config_state.l:config_target)
+    endif
+endfunction
+
+function! unreal#set_config(config) abort
+    let [l:config_state, l:config_target] = s:parse_config_state_and_target(a:config)
+    let g:unreal_config_state = l:config_state
+    let g:unreal_config_target = l:config_target
 endfunction
 
 function! unreal#set_platform(platform) abort
@@ -173,15 +354,141 @@
     let g:unreal_project_platform = a:platform
 endfunction
 
-function! unreal#build(...) abort
-    let l:opts = copy(g:unreal_auto_build_options)
-    if a:0
-        let l:opts = a:000 + l:opts
+" }}}
+
+" Build {{{
+
+function! unreal#get_ubt_args(...) abort
+    " Start with modules we should always build.
+    let l:mod_names = keys(g:unreal_auto_build_modules)
+    let l:mod_args = copy(g:unreal_auto_build_modules)
+
+    " Function arguments are: 
+    " <Project> <Platform> <Config> [<...MainModuleOptions>] [<...GlobalOptions>] <?NoGlobalModules>
+    let l:project = g:unreal_project
+    if a:0 >= 1 && !empty(a:1)
+        let l:project = a:1
+    endif
+
+    let l:platform = g:unreal_platform
+    if a:0 >= 2 && !empty(a:2)
+        let l:platform = a:2
+    endif
+
+    let [l:config_state, l:config_target] = [g:unreal_config_state, g:unreal_config_target]
+    if a:0 >= 3 && !empty(a:3)
+        let [l:config_state, l:config_target] = s:parse_config_state_and_target(a:3)
+    endif
+
+    let l:mod_opts = []
+    if a:0 >= 4
+        if type(a:4) == type([])
+            let l:mod_opts = a:4
+        else
+            let l:mod_opts = [a:4]
+        endif
+    endif
+
+    let l:global_opts = copy(g:unreal_auto_build_options)
+    if a:0 >= 5
+        if type(a:5) == type([])
+            call extend(l:global_opts, a:5)
+        else
+            call extend(l:global_opts, [a:5])
+        endif
+    endif
+
+    if a:0 >= 6 && a:6
+        let l:mod_names = []
+    endif
+
+    " Find the appropriate module for our project.
+    if l:config_target == "Editor"
+        let l:module = unreal#find_project_module_of_type(l:project, "Editor")
+    else
+        let l:module = unreal#find_project_module_of_type(l:project, "Runtime")
+    endif
+    if empty(l:module)
+        call unreal#throw("Can't find module for target '".l:config_target."' in project: ".l:project)
     endif
-    let g:unreal_temp_makeprg_args__ = l:opts
+
+    " Add the module's arguments to the list.
+    call insert(l:mod_names, l:module["Name"], 0)
+    let l:mod_args[l:module["Name"]] = l:mod_opts
+
+    " Build the argument list for our modules.
+    let l:ubt_cmdline = []
+    for l:mod_name in l:mod_names
+        let l:mod_cmdline = '-Target="'.
+                    \l:mod_name.' '.
+                    \l:platform.' '.
+                    \l:config_state
+        let l:mod_arg = l:mod_args[l:mod_name]
+        if !empty(l:mod_arg)
+            let l:mod_cmdline .= ' '.join(l:mod_arg, ' ')
+        endif
+        let l:mod_cmdline .= '"'
+
+        call add(l:ubt_cmdline, l:mod_cmdline)
+    endfor
+
+    " Add any global options.
+    call extend(l:ubt_cmdline, l:global_opts)
+
+    return l:ubt_cmdline
+endfunction
+
+function! unreal#build(bang, ...) abort
+    let g:__unreal_makeprg_script = "Build"
+    let g:__unreal_makeprg_args = call('unreal#get_ubt_args', a:000)
+    call unreal#run_make("ubuild", bang)
+endfunction
+
+function! unreal#rebuild(...) abort
+    let g:__unreal_makeprg_script = "Rebuild"
+    let g:__unreal_makeprg_args = call('unreal#get_ubt_args', a:000)
     call unreal#run_make("ubuild")
 endfunction
 
+function! unreal#clean(...) abort
+    let g:__unreal_makeprg_script = "Clean"
+    let g:__unreal_makeprg_args = call('unreal#get_ubt_args', a:000)
+    call unreal#run_make("ubuild")
+endfunction
+
+function! unreal#generate_compilation_database() abort
+    let g:__unreal_makeprg_script = "Build"
+    let g:__unreal_makeprg_args = unreal#get_ubt_args('', '', '', [], ['-allmodules', '-Mode=GenerateClangDatabase'], 1)
+    call unreal#run_make("ubuild")
+endfunction
+
+function! unreal#generate_project_files() abort
+    if !g:unreal_auto_generate_compilation_database
+        call unreal#run_make("ugenprojfiles")
+    else
+        " Generate a response file that will run both the project generation
+        " and the compilation database generation one after the other. Then we
+        " pass that to our little script wrapper.
+        let l:genscriptpath = shellescape(
+                    \unreal#get_script_path("Engine/Build/BatchFiles/GenerateProjectFiles"))
+        let l:buildscriptpath = shellescape(
+                    \unreal#get_script_path("Engine/Build/BatchFiles/Build"))
+        let l:buildscriptargs = 
+                    \unreal#get_ubt_args('', '', '', [], ['-allmodules', '-Mode=GenerateClangDatabase'], 1)
+
+        let l:rsplines = [
+                    \l:genscriptpath,
+                    \l:buildscriptpath.' '.join(l:buildscriptargs, ' ')
+                    \]
+        let l:rsppath = tempname()
+        call unreal#trace("Writing response file: ".l:rsppath)
+        call writefile(l:rsplines, l:rsppath)
+
+        let g:__unreal_makeprg_args = l:rsppath
+        call unreal#run_make("uscriptwrapper")
+    endif
+endfunction
+
 " }}}
 
 " Completion Functions {{{
@@ -202,23 +509,29 @@
     return s:add_unique_suggestion_trailing_space(l:suggestions)
 endfunction
 
+function! unreal#complete_projects(ArgLead, CmdLine, CursorPos)
+    return s:filter_suggestions(a:ArgLead, keys(g:unreal_branch_projects))
+endfunction
+
 function! unreal#complete_platforms(ArgLead, CmdLine, CursorPos)
     return s:filter_suggestions(a:ArgLead, copy(g:unreal_platforms))
 endfunction
 
 function! unreal#complete_configs(ArgLead, CmdLine, CursorPos)
-    return s:filter_suggestions(a:ArgLead, copy(g:unreal_configurations))
+    call s:cache_unreal_configs()
+    return s:filter_suggestions(a:ArgLead, copy(s:unreal_configs))
 endfunction
 
-function! unreal#complete_build_targets(ArgLead, CmdLine, CursorPos)
+function! unreal#complete_build_args(ArgLead, CmdLine, CursorPos)
     let l:bits = split(a:CmdLine.'_', ' ')
-    let l:bits = l:bits[1:]  " Remove the `UnrealBuild` command from the line
+    let l:bits = l:bits[1:]  " Remove the `UnrealBuild` command from the line.
     if len(l:bits) <= 1
-        let l:suggestions = vimcrosoft#get_sln_project_names()
+        let l:suggestions = keys(g:unreal_branch_projects)
     elseif len(l:bits) == 2
         let l:suggestions = copy(g:unreal_platforms)
     elseif len(l:bits) == 3
-        let l:suggestions = copy(g:unreal_configurations)
+        call s:cache_unreal_configs()
+        let l:suggestions = s:unreal_configs
     elseif len(l:bits) >= 4
         let l:suggestions = copy(g:unreal_build_options)
     endif
@@ -229,12 +542,26 @@
 
 " Build System {{{
 
-function! unreal#run_make(compilername) abort
+function! unreal#run_make(compilername, ...) abort
+    let l:bang = 0
+    if a:0 && a:1
+        let l:bang = 1
+    endif
+
     execute "compiler ".a:compilername
+
     if exists(':Make')  " Support for vim-dispatch
-        Make
+        if l:bang
+            Make!
+        else
+            Make
+        endif
     else
-        make
+        if l:bang
+            make!
+        else
+            make
+        endif
     endif
 endfunction
 
@@ -245,7 +572,12 @@
 let s:builds_in_progress = []
 
 function! unreal#get_script_path(scriptname, ...) abort
-    return g:unreal_project_dir.s:dirsep.a:scriptname.s:scriptext
+    if s:iswin
+        let l:name = substitute(a:scriptname, '/', "\\", 'g')
+    else
+        let l:name = a:scriptname
+    endif
+    return g:unreal_branch_dir.s:dirsep.l:name.s:scriptext
 endfunction
 
 " }}}
@@ -254,7 +586,7 @@
 
 function! unreal#init() abort
     if g:unreal_auto_find_project
-        call unreal#find_project_dir()
+        call unreal#find_branch_dir_and_project()
     endif
 endfunction
 
@@ -263,12 +595,13 @@
 " Statusline Functions {{{
 
 function! unreal#statusline(...) abort
-    if empty(g:unreal_project_dir)
+    if empty(g:unreal_branch_dir)
         return ''
     endif
-
-    let l:line = 'UE:'.g:unreal_project_dir
-    return l:line
+    if empty(g:unreal_project)
+        return 'UE:'.g:unreal_branch_dir.':<no project>'
+    endif
+    return 'UE:'.g:unreal_branch_dir.':'.g:unreal_project.'('.g:unreal_config_state.g:unreal_config_target.'|'.g:unreal_platform.')'
 endfunction
 
 " }}}