#lang racket/base
(require drracket/tool
(provide tool@)

(define coverage-suffix ".rktcov")
(define coverage-label "Code Coverage")
(define button-label "Load Code Coverage")

(define tool@
    (import drracket:tool^ )
    (export drracket:tool-exports^)

    (define coverage-button-mixin
      (mixin (drracket:unit:frame<%>) ()
        (inherit get-button-panel
        ;Applies code coverage highlighting to all open files. Displays
        ; a dialog with a list of files covered by the currently in focus file
        ; and allows the user to select a file to open and jump to. Coverage
        ; information is first looked for in DrRacket (the program has just been run)
        ; If the program has not been run, or has been modified to invalidate it's
        ; coverage information, look in the compiled directory for coverage info
        ; and display that.
        (define (load-coverage)
          (let* ([current-tab (get-current-tab)]
                 [source-file (send (send current-tab get-defs) get-filename)]
                 [coverage-file (get-temp-coverage-file source-file)]
                 [test-coverage-info-ht (get-test-coverage-info-ht current-tab coverage-file)])
            (when test-coverage-info-ht
                (let* ([coverage-report-list (make-coverage-report test-coverage-info-ht coverage-file)]
                       [frame-group (group:get-the-frame-group)]
                       [choice-pair (get-covered-files-from-user
                                                 (format "Files covered by ~a" source-file)
                                                 (map (λ (item) (format "~a~a (~a%)" (first item) (if (second item) "" "*") (third item))) coverage-report-list))]
                       [choice-open-with (first choice-pair)]
                       [choice-index-list (last choice-pair)]
                  ;switch to or open a new frame with the selected file and display the uncoverd lines in a new dialog
                  (when choice-index-list
                    (map (λ (choice-index)
                           (let* ([coverage-report-item (list-ref coverage-report-list choice-index)]
                                  [coverage-report-file (string->path (first coverage-report-item))]
                                  [coverage-report-lines (last coverage-report-item)])
                             (handler:edit-file coverage-report-file)
                             (when (and choice-open-with (> (length coverage-report-lines) 0))
                               (send (uncovered-lines-dialog coverage-report-file coverage-report-lines) show #t))
                  ;send the coverage info to all files found in the coverage-report
                  (map (λ (report-item)
                         (let* ([coverage-report-file (string->path (first report-item))]
                                [located-file-tab (locate-file-tab frame-group coverage-report-file)])
                           (when located-file-tab
                             (send located-file-tab show-test-coverage-annotations test-coverage-info-ht #f #f #f))
        ;Get the given tab's coverage info, either from drrackets current test-coverage-info (if it has been run) or from
        ; a saved one. If the test coverage does not need to be loaded (the program has recently been run) save it to
        ; coverage-file. If the test coverage needs to be loaded then check if the given tab has
        ; been modified since the coverage was saved and display a warning if it has. If no coverage information can
        ; be found display a warning with suggestions to fix it.
        ;drracket:unit:tab<%> path? -> (or #f test-coverage-info)
        (define (get-test-coverage-info-ht current-tab coverage-file)
          (let* ([source-file (send (send current-tab get-defs) get-filename)]
                 [interactions-text (get-interactions-text)]
                 [test-coverage-info-drracket (send interactions-text get-test-coverage-info)])
            (if test-coverage-info-drracket
                  (when coverage-file
                      (save-test-coverage-info test-coverage-info-drracket coverage-file))
                  (send interactions-text set-test-coverage-info #f) ;clear out drrackets test-coverage-info-ht so we can use our
                                                                     ;coverage file modified time as a reference for when coverage
                                                                     ;was last run
                (if (and coverage-file (file-exists? coverage-file))
                    (if (and 
                         (not (is-file-still-valid? source-file coverage-file))
                         (equal? (message-box coverage-label 
                                              "The Coverage information may be out of date. Run the program to update it." 
                                              (list 'ok-cancel 'caution))
                        (load-test-coverage-info coverage-file))
                      (message-box coverage-label 
                             (format "No Code Coverage Information found for ~a. Make sure the program has been run and Syntactic Test Suite Coverage is enabled in Language->Chosse Language...->Dynamic Properties." source-file)
                             (list 'ok 'stop))
        ;Creates the load coverage button and add it to the menu bar in DrRacket
        (define load-button (new switchable-button%
                                 (label button-label)
                                 (callback (λ (button)
                                 (parent (get-button-panel))
                                 (bitmap code-coverage-bitmap)
        (register-toolbar-button load-button)
        (send (get-button-panel) change-children
              (λ (l)
                (cons load-button (remq load-button l))))     
    ;Takes a test-coverage-info-ht and returns a sorted (alphibetical, but with uncovered
    ;files first) list of file-name coverage-is-valid? %covered uncovered-lines.
    ;hasheq path -> (list string?  boolean? integer? (list integer?))
    (define (make-coverage-report test-coverage-info-ht coverage-file)
      (let* ([file->lines-ht (make-hash)])
        (hash-for-each test-coverage-info-ht 
                       (λ (key value)
                         (let* ([line (syntax-line key)]
                                [source (format "~a" (syntax-source key))]
                                [covered? (mcar value)]
                                [file->lines-value (hash-ref file->lines-ht source (list (is-file-still-valid? (string->path source) coverage-file) 0 (list)))])
                           (hash-set! file->lines-ht source 
                                      (list (first file->lines-value) 
                                            (max line (second file->lines-value))
                                            (if (or covered? (member line (last file->lines-value)))
                                                (last file->lines-value)
                                                (sort (append (last file->lines-value) (list line)) <)))
        (let* ([test-coverage-info-list (sort (map (λ (item) (list (first item) 
                                                                   (second item)
                                                                   (round (* (- 1 (/ (length (last item)) (third item))) 100)) ;compute uncoverd line %
                                                                   (last item))) (hash->list file->lines-ht) )
                                              (λ (a b) (< (third a) (third b))))])
    ;Determine coverage-file coverage info will still be valid for file. If file has been updated/modified
    ;more recently than coverage-file this indicates that coverage-file's coverage info may not be valid for file
    (define (is-file-still-valid? file coverage-file)
      (if coverage-file
          (let* ([file-modify-valid? (> (file-or-directory-modify-seconds coverage-file) (file-or-directory-modify-seconds file))]
                 [located-file-frame (send (group:get-the-frame-group) locate-file file)]
                 [file-untouched-valid? (if located-file-frame
                                            (not (send (send located-file-frame get-editor) is-modified?)) ;dosnt work for individual tabs
            (and file-modify-valid? file-untouched-valid?)
          #t ;no coverage-file indicating that the source file has not been saved, so they only way we could have coverage info
          ;is if we got drracket's which means it is up to date.

    ;Get the name and location of a code coverage file based on the name of a source file or
    ;#f if the source file has not been saved. Also creates coverage dir if it does not exisit
    ;path? -> (or path? #f)
    (define (get-temp-coverage-file source-file)
      (if source-file
          (let* ([file-base (file-dir-from-path source-file)]
                 [file-name (file-name-from-path source-file)]
                 [temp-coverage-file-name (path-replace-suffix file-name coverage-suffix)]
                 [temp-coverage-dir (build-path file-base "compiled")]
                 [temp-coverage-file (build-path temp-coverage-dir temp-coverage-file-name)])
            (when (not (directory-exists? temp-coverage-dir))
              (make-directory temp-coverage-dir))
    ;Get a the directory from path
    (define (file-dir-from-path path)
      (define-values (file-dir file-name must-be-dir) (split-path path))
    ;writes the test-coiverage-info hash table to the given file so that "load-test-coverage-info"
    ;can reconstruct the hash table
    ;hasheq path -> void
    (define (save-test-coverage-info test-coverage-info coverage-file)
      (with-output-to-file coverage-file
        (lambda () (begin 
                     (write (hash-map test-coverage-info 
                                      (λ (key value)
                                        (cons (list (serialize (syntax-source key)) 
                                                    (syntax-position key) 
                                                    (syntax-span key)
                                                    (syntax-line key)) 
          #:mode 'text
          #:exists 'replace
    ;Convert the coverage file to a test-coverage-info hash table
    ;path -> hasheq
    (define (load-test-coverage-info coverage-file)
      (make-hasheq (map (lambda (element)
                          (let* ([key (car element)]
                                 [value (cdr element)])
                            (cons (datum->syntax #f (void) (list (deserialize (car key)) (cadddr key) 1 (cadr key) (caddr key))) (mcons (car value) (cdr value)))))
                        (read (open-input-file coverage-file)))))
    ;Locates the tab with the given file name from a group of frames
    (define (locate-file-tab frame-group file)
      (let*  ([located-file-frame (send frame-group locate-file file)]
              [located-file-tab (if located-file-frame
                                    (findf (λ (t)
                                              (send (send t get-defs) get-filename)
                                           (send located-file-frame get-tabs))
    (define (get-listbox-min-height num-items)
      (inexact->exact (min 500 (round (sqrt (* 600 num-items)))))) 
    ;Similar to get-choices-from user, but has two open buttons. One with uncovered lines dialog and one without
    ;string? (list string?) -> (list boolean? (list integer?))
    (define (get-covered-files-from-user message choices)
      (define button-pressed (box 'close))
      (define (button-callback button) 
        (λ (b e)
          (set-box! button-pressed button)
          (send dialog show #f)
      (define (enable-open-buttons enable?)
        (send open-button enable enable?)
        (send open-with-button enable enable?))
      (define dialog (instantiate dialog% (coverage-label)))
      (new message% [parent dialog] [label message])
      (define list-box (new list-box% 
                            [label ""]
                            [choices choices]
                            [parent dialog]
                            [style '(multiple)]
                            [min-height (get-listbox-min-height (length choices))]
                            [callback (λ (c e) 
                                        (if (> (length (send list-box get-selections)) 0)
                                            (if (eq? (send e get-event-type) 'list-box-dclick)
                                                ((button-callback 'open) null null)
                                                (enable-open-buttons #t))
                                            (enable-open-buttons #f)))
      (define panel (new horizontal-panel% [parent dialog]
                         [alignment '(right bottom)]))
      (define open-button (new button% [parent panel] 
                               [label "Open"]
                               [callback (button-callback 'open)]
                               [enabled #f]
                               [style '(border)]))
      (define open-with-button (new button% [parent panel] 
                                    [label "Open With Uncoverd Lines Dialog"]
                                    [callback (button-callback 'open-with)]
                                    [enabled #f]))
      (new button% [parent panel] 
           [label "Close"]
           [callback (button-callback 'close)])
      (send dialog show #t)
      (case (unbox button-pressed)
        ['open (list #f (send list-box get-selections))]
        ['open-with (list #t (send list-box get-selections))]
        [else (list #f #f)])
    ; the dialog that displays the uncovered lines. Not a message box so the user can still interact
    ; with DrRacket without having to close the dialog.
    (define (uncovered-lines-dialog file lines)
      (let* ([dialog (instantiate frame% (coverage-label))])
        (new message% 
             [parent dialog] 
             [label "Lines containing uncovered code in"])
        (new message% 
             [parent dialog]
             [label (format "~a:" file)])
        (new list-box%
             [label ""]	 
             [choices (map (λ (l) (format "~a" l)) lines)]	 
             [parent dialog]
             [min-height (get-listbox-min-height (length lines))])
        (define panel (new horizontal-panel% 
                           [parent dialog]
                           [alignment '(right bottom)]))
        ;(new button% [parent panel] [label "Go To Line"]
        ;     [callback (λ (b e) (send dialog show #f))])
        (new button% [parent panel] [label "Close"]
             [callback (λ (b e) (send dialog show #f))])
    ; Graphic for the code coverage button
    (define code-coverage-bitmap 
      (let* ((bmp (make-bitmap 16 16))
             (bdc (make-object bitmap-dc% bmp)))
        (send bdc erase)
        (send bdc set-smoothing 'smoothed)
        (send bdc set-pen "black" 1 'transparent)
        (send bdc set-brush "forest green" 'solid)
        (send bdc draw-rectangle 2 5 12 9)
        (send bdc set-brush "maroon" 'solid)
        (send bdc draw-rectangle 11 5 14 9)
        (send bdc set-bitmap #f)
    (define (phase1) (void))
    (define (phase2) (void))
    (drracket:get/extend:extend-unit-frame coverage-button-mixin)))