/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 * http://www.mozilla.org/MPL/
 *
 * Software distributed under the License is distributed on an "AS IS" basis,
 * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
 * for the specific language governing rights and limitations under the
 * License.
 *
 * The Original Code is Ajax.org Code Editor (ACE).
 *
 * The Initial Developer of the Original Code is
 * Ajax.org B.V.
 * Portions created by the Initial Developer are Copyright (C) 2010
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *      Fabian Jakobs <fabian AT ajax DOT org>
 *
 * Alternatively, the contents of this file may be used under the terms of
 * either the GNU General Public License Version 2 or later (the "GPL"), or
 * the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
 * of those above. If you wish to allow use of your version of this file only
 * under the terms of either the GPL or the LGPL, and not to allow others to
 * use your version of this file under the terms of the MPL, indicate your
 * decision by deleting the provisions above and replace them with the notice
 * and other provisions required by the GPL or the LGPL. If you do not delete
 * the provisions above, a recipient may use your version of this file under
 * the terms of any one of the MPL, the GPL or the LGPL.
 *
 * ***** END LICENSE BLOCK ***** */

define(function(require, exports, module) {

var Range = function(startRow, startColumn, endRow, endColumn) {
    this.start = {
        row: startRow,
        column: startColumn
    };

    this.end = {
        row: endRow,
        column: endColumn
    };
};

(function() {

    this.toString = function() {
        return ("Range: [" + this.start.row + "/" + this.start.column +
            "] -> [" + this.end.row + "/" + this.end.column + "]");
    };

    this.contains = function(row, column) {
        return this.compare(row, column) == 0;
    };

    /**
     * Compares this range (A) with another range (B), where B is the passed in
     * range.
     *
     * Return values:
     *  -2: (B) is infront of (A) and doesn't intersect with (A)
     *  -1: (B) begins before (A) but ends inside of (A)
     *   0: (B) is completly inside of (A) OR (A) is complety inside of (B)
     *  +1: (B) begins inside of (A) but ends outside of (A)
     *  +2: (B) is after (A) and doesn't intersect with (A)
     *
     *  42: FTW state: (B) ends in (A) but starts outside of (A)
     */
    this.compareRange = function(range) {
        var cmp,
            end = range.end,
            start = range.start;

        cmp = this.compare(end.row, end.column);
        if (cmp == 1) {
            cmp = this.compare(start.row, start.column);
            if (cmp == 1) {
                return 2;
            } else if (cmp == 0) {
                return 1;
            } else {
                return 0;
            }
        } else if (cmp == -1) {
            return -2;
        } else {
            cmp = this.compare(start.row, start.column);
            if (cmp == -1) {
                return -1;
            } else if (cmp == 1) {
                return 42;
            } else {
                return 0;
            }
        }
    }

    this.containsRange = function(range) {
        var cmp = this.compareRange(range);
        return (cmp == -1 || cmp == 0 || cmp == 1);
    }

    this.isEnd = function(row, column) {
        return this.end.row == row && this.end.column == column;
    }

    this.isStart = function(row, column) {
        return this.start.row == row && this.start.column == column;
    }

    this.setStart = function(row, column) {
        if (typeof row == "object") {
            this.start.column = row.column;
            this.start.row = row.row;
        } else {
            this.start.row = row;
            this.start.column = column;
        }
    }

    this.setEnd = function(row, column) {
        if (typeof row == "object") {
            this.end.column = row.column;
            this.end.row = row.row;
        } else {
            this.end.row = row;
            this.end.column = column;
        }
    }

    this.inside = function(row, column) {
        if (this.compare(row, column) == 0) {
            if (this.isEnd(row, column) || this.isStart(row, column)) {
                return false;
            } else {
                return true;
            }
        }
        return false;
    }

    this.insideStart = function(row, column) {
        if (this.compare(row, column) == 0) {
            if (this.isEnd(row, column)) {
                return false;
            } else {
                return true;
            }
        }
        return false;
    }

    this.insideEnd = function(row, column) {
        if (this.compare(row, column) == 0) {
            if (this.isStart(row, column)) {
                return false;
            } else {
                return true;
            }
        }
        return false;
    }

    this.compare = function(row, column) {
        if (!this.isMultiLine()) {
            if (row === this.start.row) {
                return column < this.start.column ? -1 : (column > this.end.column ? 1 : 0);
            };
        }

        if (row < this.start.row)
            return -1;

        if (row > this.end.row)
            return 1;

        if (this.start.row === row)
            return column >= this.start.column ? 0 : -1;

        if (this.end.row === row)
            return column <= this.end.column ? 0 : 1;

        return 0;
    };

    /**
     * Like .compare(), but if isStart is true, return -1;
     */
    this.compareStart = function(row, column) {
        if (this.start.row == row && this.start.column == column) {
            return -1;
        } else {
            return this.compare(row, column);
        }
    }

    /**
     * Like .compare(), but if isEnd is true, return 1;
     */
    this.compareEnd = function(row, column) {
        if (this.end.row == row && this.end.column == column) {
            return 1;
        } else {
            return this.compare(row, column);
        }
    }

    this.compareInside = function(row, column) {
        if (this.end.row == row && this.end.column == column) {
            return 1;
        } else if (this.start.row == row && this.start.column == column) {
            return -1;
        } else {
            return this.compare(row, column);
        }
    }

    this.clipRows = function(firstRow, lastRow) {
        if (this.end.row > lastRow) {
            var end = {
                row: lastRow+1,
                column: 0
            };
        }

        if (this.start.row > lastRow) {
            var start = {
                row: lastRow+1,
                column: 0
            };
        }

        if (this.start.row < firstRow) {
            var start = {
                row: firstRow,
                column: 0
            };
        }

        if (this.end.row < firstRow) {
            var end = {
                row: firstRow,
                column: 0
            };
        }
        return Range.fromPoints(start || this.start, end || this.end);
    };

    this.extend = function(row, column) {
        var cmp = this.compare(row, column);

        if (cmp == 0)
            return this;
        else if (cmp == -1)
            var start = {row: row, column: column};
        else
            var end = {row: row, column: column};

        return Range.fromPoints(start || this.start, end || this.end);
    };

    this.isEmpty = function() {
        return (this.start.row == this.end.row && this.start.column == this.end.column);
    };

    this.isMultiLine = function() {
        return (this.start.row !== this.end.row);
    };

    this.clone = function() {
        return Range.fromPoints(this.start, this.end);
    };

    this.collapseRows = function() {
        if (this.end.column == 0)
            return new Range(this.start.row, 0, Math.max(this.start.row, this.end.row-1), 0)
        else
            return new Range(this.start.row, 0, this.end.row, 0)
    };

    this.toScreenRange = function(session) {
        var screenPosStart =
            session.documentToScreenPosition(this.start);
        var screenPosEnd =
            session.documentToScreenPosition(this.end);

        return new Range(
            screenPosStart.row, screenPosStart.column,
            screenPosEnd.row, screenPosEnd.column
        );
    };

}).call(Range.prototype);


Range.fromPoints = function(start, end) {
    return new Range(start.row, start.column, end.row, end.column);
};

exports.Range = Range;
});