From 9d659a0af41bd8fbdd0163c39343d9cb96b888e7 Mon Sep 17 00:00:00 2001
From: Jonas Widen <jonas.widen@widens.eu>
Date: Sun, 16 Mar 2025 21:21:56 +0100
Subject: [PATCH] Added completion

---
 lua/gemini/completion.lua | 71 +++++++++++++++++++++++++++++++++++++++
 lua/gemini/init.lua       | 31 +++++++++++++++++
 2 files changed, 102 insertions(+)
 create mode 100644 lua/gemini/completion.lua

diff --git a/lua/gemini/completion.lua b/lua/gemini/completion.lua
new file mode 100644
index 0000000..3b5fc1f
--- /dev/null
+++ b/lua/gemini/completion.lua
@@ -0,0 +1,71 @@
+local api = require("gemini.api")
+local M = {}
+
+-- Cache for completion items
+local completion_cache = {}
+
+-- Helper function to create completion items from Gemini response
+local function parse_completion_response(response)
+    -- Split response into lines and filter out empty ones
+    local lines = vim.split(response, "\n")
+    local items = {}
+    
+    for _, line in ipairs(lines) do
+        if line and line:match("^%s*[^%s]") then -- Skip empty lines
+            table.insert(items, {
+                label = line,
+                kind = vim.lsp.protocol.CompletionItemKind.Text,
+                detail = "Gemini suggestion",
+                documentation = {
+                    kind = "markdown",
+                    value = "```\n" .. line .. "\n```"
+                }
+            })
+        end
+    end
+    
+    return items
+end
+
+function M.get_completion(params, callback)
+    local cursor = vim.api.nvim_win_get_cursor(0)
+    local line = cursor[1]
+    local col = cursor[2]
+    
+    -- Get current buffer content for context
+    local lines = vim.api.nvim_buf_get_lines(0, math.max(0, line - 10), line, false)
+    local prefix = table.concat(lines, "\n")
+    
+    -- Get current line up to cursor
+    local current_line = vim.api.nvim_get_current_line()
+    local before_cursor = string.sub(current_line, 1, col)
+    
+    -- Construct prompt for Gemini
+    local prompt = string.format(
+        "Complete this code. Only provide the completion, no explanation:\n%s\n%s",
+        prefix,
+        before_cursor
+    )
+    
+    -- Check cache first
+    local cache_key = prefix .. before_cursor
+    if completion_cache[cache_key] then
+        callback(completion_cache[cache_key])
+        return
+    end
+    
+    -- Get completion from Gemini
+    api.get_response(prompt, nil, function(response, error)
+        if error then
+            vim.notify("Completion error: " .. error, vim.log.levels.ERROR)
+            callback({})
+            return
+        end
+        
+        local items = parse_completion_response(response)
+        completion_cache[cache_key] = items
+        callback(items)
+    end)
+end
+
+return M
\ No newline at end of file
diff --git a/lua/gemini/init.lua b/lua/gemini/init.lua
index 72aa3a6..3aa7536 100644
--- a/lua/gemini/init.lua
+++ b/lua/gemini/init.lua
@@ -3,6 +3,7 @@
 local api = require("gemini.api")
 local chat = require("gemini.chat")
 local config = require("gemini.config")
+local completion = require("gemini.completion")
 
 local M = {}
 
@@ -42,6 +43,13 @@ function M.setup(opts)
     config.setup(opts)
     pcall(vim.treesitter.language.require_language, "markdown")
 
+    -- Register completion source
+    vim.api.nvim_create_autocmd("LspAttach", {
+        callback = function(args)
+            vim.bo[args.buf].omnifunc = "v:lua.require'gemini.completion'.get_completion"
+        end,
+    })
+
     vim.api.nvim_create_user_command("Gemini", function(opts)
         if opts.args == "" then
             vim.notify("Please provide a prompt for Gemini.", vim.log.levels.WARN)
@@ -75,6 +83,29 @@ function M.setup(opts)
         chat.clear()
         vim.notify("Chat history cleared", vim.log.levels.INFO)
     end, { desc = "Clear Gemini chat history" })
+
+    -- Map <C-Space> to trigger Gemini completion
+    vim.keymap.set('i', '<C-Space>', function()
+        vim.api.nvim_feedkeys(vim.api.nvim_replace_termcodes('<C-x><C-o>', true, true, true), 'n', true)
+    end, { desc = 'Trigger Gemini completion' })
+end
+
+function M.complete(findstart, base)
+    if findstart == 1 then
+        local line = vim.api.nvim_get_current_line()
+        local col = vim.api.nvim_win_get_cursor(0)[2]
+        local start = col
+        while start > 0 and string.match(line:sub(start, start), "[%w_]") do
+            start = start - 1
+        end
+        return start
+    else
+        local items = {}
+        completion.get_completion({ word = base }, function(completions)
+            items = completions
+        end)
+        return items
+    end
 end
 
 return M